# Twice the Run Time and Brighter… B90 Upgrade



## SilverFox (Feb 16, 2006)

Does this seem too good to be true? Well it is true.

However, there is a catch.

Jim Sexton and I are teaming up to make a NiMh battery stick that will fit B90 powered lights. These include the 8NX, 8AX, 9AN, and L7.

We have settled on the GP 3700 sub C cells. They are good performers and have a proven track record. They are a bit on the expensive side, but I think the quality is worth it.

We also looked at some Sanyo 2400 mAh NiCd cells, but the GP’s are so much better that we decided just to offer them.

Jim sent me a prototype to test. We have a couple of things to work out, but I was getting 95 minutes run time with the GP pack. I normally get 47 minutes from my SureFire B90 pack.

In addition, the GP pack was able to hold a higher voltage under load. A higher voltage means a bit brighter lamp output. Jim figured out that it is around a 14% increase in lumens. The 8NX runs a little bit on the warm side, so I noticed that at the end of the GP run, it was about the same color as the start of the run with the stock pack.

Here is a rough graph that shows the difference in performance at a 2 amp draw.







A while back SureFire had some problems with the B90 batteries. They changed battery manufacturers (we think), altered the way they check the packs prior to shipping, and changed the charger. This new charger does a fast charge, then the green light comes on. For a full charge, you leave the pack on the charger until the green light starts to blink. The older charger did not have the blinking green LED at the end of the charge.

The stock charger charges this GP battery pack without problems. The time takes longer, but the cells only get to around 95F and the end of charge termination seems to work fine.

The GP pack does the bulk charge in around 75 minutes, then it takes about 95 more minutes until the green LED starts flashing. This is a real plus. No additional charger is needed, as long as you have the newer charger.

The GP cells are a little bit bigger in diameter, so we are having to come up with custom hardware to make things work. I had no problems with fit in my 8NX, but we will have to check the inside diameter of the aluminum lights to make sure there is room.

Let me know your comments. Right now I have the only GP pack. My 8NX got hot during the run time, but I usually don’t use it continuous. Is there any other issues I have missed?

Tom

Edit: I am now taking orders in this thread.


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## SilverFox (Feb 16, 2006)

*Re: Twice the Run Time and Brighter…*

Wow, it's a little bit hard to read the legend on the graph...

The green line is the GP 3700 pack, the red line is the Sanyo 2400 NiCd pack that we were playing with, and the black line is the stock B90 (1800 mAh, I think) pack.

Tom


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## PGP (Feb 16, 2006)

*Re: Twice the Run Time and Brighter…*

Sounds great. I was planning on getting a third B90 since it seems like one of them is not holding a charge for very long. The only problem I will have is that my 9AN charger is the old style that does not blink! The GP 3700 pack wont work with that charger at all!

Patrick


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## DonX_Fi (Feb 16, 2006)

*Re: Twice the Run Time and Brighter…*

I also have older type charge in My 8XN, but still this Is VERY GOOD news.
Sure I want new batteries. That would get my old workhorse alive again.


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## SilverFox (Feb 17, 2006)

*Re: Twice the Run Time and Brighter…*

Hello Patric and Juha,

I have not tried charging the GP pack in the older SureFire charger, so I don't know if there are any issues with it or not. I may have to try and find one locally and try it out.

We did not know if it would work on the charger at all. I was very pleased that it worked fine.

Perhaps you can get a deal from SureFire on a charger upgrade...

Tom


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## missionaryman (Feb 17, 2006)

*Re: Twice the Run Time and Brighter…*

why would you use the GP3700's when this is what the supplier advises: "Consider Elite 3600 instead. Better performance and lower price guaranteed.Try IB3800 or Elite3600's. Both outperform GP3700 and cost less."????

wouldn't it be better to use the IB4200? They are meant to be able to sustain even better voltage and have another 500mah capacity.
I don't mean to be abrupt but to me it just looks like a no brainer.


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## SilverFox (Feb 17, 2006)

*Re: Twice the Run Time and Brighter…*

Hello Missionaryman,

We chose the GP 3700 cells because they are high quality, consistent in capacity and performance from cell to cell, have a high cycle life, don't leak, have the right diameter and length for our application, and held up very well at the expected 2 amp current draw in our application.

The IB 4200 cells are very attractive, but they are just too big to fit, the same goes for the Elite 3600 cells.

So, do you have a light that uses the B90 battery that you are interested in getting better performance from?

Tom


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## hector (Feb 18, 2006)

*Re: Twice the Run Time and Brighter…*

Looks great, 95 minutes would be a nice improvement. That's a whole evening of monkeying around for me. Nice not to have to change cells. Only little worry is that with brighter output, how much do you think the life of the bulb could get shortened, since the SFs are already overdriven with a 30 hour life?


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## CLHC (Feb 18, 2006)

*Re: Twice the Run Time and Brighter…*

Wow this is interesting news! The batteries running my SureFire 8X and SF.9N have outlived their usefullness allowing on "sprints" with lower light output. Looking forward to hear more on these batteries!

Thanks!


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## SilverFox (Feb 18, 2006)

*Re: Twice the Run Time and Brighter…*

Hello Hector,

I only have an 8NX. The stock battery pack seems to under drive this lamp a bit. My current lamp is the original that came with the light. This light has been used a lot over the last 18 months, and is still going strong. I have not tracked the actual hours of use, but am pretty sure I am over 30 hours.

I don't know how much life expectancy you loose, but Jim figured that the increase in voltage will amount to a 14% increase in lumens. I believe this is a pretty gentle overdrive amount...

Tom


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## missionaryman (Feb 19, 2006)

*Re: Twice the Run Time and Brighter…*

thanks Silverfox - makes perfect sense in that context, don't actually have a light that uses that pack but was looking into using SUB C's for a different application so been doing some research.



SilverFox said:


> Hello Missionaryman,
> 
> We chose the GP 3700 cells because they are high quality, consistent in capacity and performance from cell to cell, have a high cycle life, don't leak, have the right diameter and length for our application, and held up very well at the expected 2 amp current draw in our application.
> 
> ...


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## cqbdude (Feb 19, 2006)

*Re: Twice the Run Time and Brighter…*

How do you tell if you have an old charger..
I had to return 3 B90 to surefire awhile back because the batteries wont hold their charge..
I do have the 8NX...


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## PGP (Feb 19, 2006)

*Re: Twice the Run Time and Brighter…*

I dont have a problem with the charger! I just checked & mine is the newer model that blinks green when 100% charged. :rock: 

Count me in for sure!  

:goodjob: guys

:thanks: 
Patrick


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## SilverFox (Feb 19, 2006)

*Re: Twice the Run Time and Brighter…*

Hello Cqbdude,

Welcome to CPF.

The new chargers signal the end of the fast charge with a green LED. If you leave the battery on the charger, the green LED will start to blink. The older chargers did not blink.

Tom


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## PGP (Feb 19, 2006)

*Re: Twice the Run Time and Brighter…*

The newer chargers are red LED lit to show initial fast charge for 2 hours then green LED comes on(80%). After a while (time not specified) green LED will blink indicating 100% charge. Then provide a maintenace charge after that. Read the manual last night.

Patrick


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## cqbdude (Feb 19, 2006)

*Re: Twice the Run Time and Brighter…*



SilverFox said:


> Hello Cqbdude,
> 
> Welcome to CPF.
> 
> ...


 

Thank You for the warm welcome...

I do have the charger that both has a green and red led indicator on it..
I will have to charge one of my b90 and actually watch and see if it blinks..
I usually use the charge and forget method..:lolsign: 

Thanks for the tip...


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## js (Feb 22, 2006)

*Re: Twice the Run Time and Brighter…*

OK. Here's an update:

It's looking like we can do this for sure, one way or another, but in the worst case scenario, there will be a $320 charge for hardware costs, plus I would need to solder on the positive nipple myself, plus the cost of the cells, plus the cost of the pack assembly, plus shipping to me so I can install the nipples, plus some token amount of money for my time to make the nipples from brass rod and solder them on, plus the cost to ship them out to people.

In the best case scenario, I will be able to find a negative ring contact / washer that has a minimum order of 100 intsead of 1000, and the battery company I am working with will be able to do the nipples on the positive contact without a $3,000 tooling fee (YIKES!!!) and for a reasonable per pack cost for this smallish run.

But however it happens it WILL happen if there is enough interest. The more packs that we commit to, the cheaper the per pack price will be. If we do 50 packs, even the $320 cost for the washers will only amount to $6 or so dollars extra per pack. 20 packs pushes it up to $16, and anything less than that is too small a run to bother having done by a company, and would get kicked over into a hand assembly situation (by me, unfortunately).

However, if I can just buy 100 washers instead of 1000, then we're talking $35 or so instead of $320. Then we're definitely in business.

But, however we do this, we just have to do it, because it is just so amazing that the stock charger will charge the GP3700 NiMH cells, and that they fit both the charger and the light, and that they have so much better performance than the stock pack. It's the best we could have hoped for, really.


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## PGP (Feb 22, 2006)

*Re: Twice the Run Time and Brighter…*

JS thanks for the time & effort you have put in to this, I hope you will be able to find someone that will sell the washers in 100 packs.

I am definetly in for 1 and if they are not to expensive I may get 2.

:thanks: 
Patrick


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## RAF_Groundcrew (Feb 23, 2006)

*Re: Twice the Run Time and Brighter…*

I think I got lost in all the numbers, what would the estimated cost per pack be?


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## SilverFox (Feb 23, 2006)

*Re: Twice the Run Time and Brighter…*

Hello Nigel,

The details are still in the works, so we are unable to know our actual costs. With that in mind, our target price is around $35 per pack.

Tom


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## Tom M (Mar 1, 2006)

*Re: Twice the Run Time and Brighter…*

I would be in for one. -Tom


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## Vranasaurus (Mar 3, 2006)

*Re: Twice the Run Time and Brighter…*

I would be interested in one maybe 2 depending on price.


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## cnjl3 (Mar 4, 2006)

*Re: Twice the Run Time and Brighter…*

put my name in the hat for one or two depending on the price.


It's so nice to have options other than "surefire".

Thank you for your hard work and i hope this build happens.

cnj


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## Luminator (Mar 4, 2006)

*Re: Twice the Run Time and Brighter…*

I'd take 3 packs, please sign me in. Currently owning two brandnew B90's (came with the L7 package) and one 10-year-old B90, still working. 

I hope you'll ship to europe as well, do you?


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## wquiles (Mar 4, 2006)

*Re: Twice the Run Time and Brighter…*

I don't own a light that takes the B90, but great project guys :bow:

Will


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## SilverFox (Mar 5, 2006)

*Re: Twice the Run Time and Brighter…*

Hello Luminator,

Welcome to CPF.

I think some arrangements can be made to get a shipment to you.

I believe I will be back in testing mode on this battery pack next week. We are still working on some details and hope that they will work out quickly. Once we have everything in place, I will let everyone know and we can go from there.

Tom


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## elnino (Mar 5, 2006)

*Re: Twice the Run Time and Brighter…*

I have an old SF 9N with a B92 ni-cd in it right now. If your pack would fit by
light I would be in for one or two, depending on the final price. Thanks.


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## js (Apr 6, 2006)

*Re: Twice the Run Time and Brighter…*

Well, I guess SilverFox is the late-bird this week and I will get the worm. hehe.

The worm being an update to this thread of course.

OK, so I found an appropriate washer that was IN STOCK at the company, and thus we are able to order only 100 pcs instead of 1,000, which is the minimum order for a washer they do NOT have in stock, but do make.

So that takes care of the negative ring at the top. I can't remember if I described how this will work, but it's pretty simple. Instead of two ribbons running down the side of the pack from a top collar sitting over an insulating washer which keeps it centered, we have a top washer and THREE ribbons equally spaced around it that run down the sides. The three ribbons keep the washer centered, and we dispense entirely with the insulating washer and instead rely on the insulating washer of the top cell itself, the cells own shrink wrap, and the shrink wrap over the three cell stick. That's plenty of insulation! Then there is a final layer of shrink wrap over the whole stick and three ribbons, which is trimmed flush to the top of the negative washer.

However, for a while, that still left the problem of the positive nipple. And that has now been solved. The guy from the company we are using to make up these battery packs (he and his wife more or less ARE the company) found a metal part that will fit the bill almost perfectly--just needs to have its bottom flange diameter made smaller by a little bit.

This is REALLY good news, people. The positive nipple is the part that people were telling me would cost $3,000 just to tool up to make it. Pretty steep for a couple dozen packs.

Actually, the **really** great news is that I won't have to do any manual work whatsoever on these packs. YEEEEEE HAAAAA.

We are acquiring the washers (Tom, I sent you an email about that--why don't you buy them? The company is annoying me :devil: ) and I will be having cells sent to our battery pack maker so that he can make up a couple sample packs for me and Tom to check out.

After that is done and all kinks are worked out, we will open 'er up. Cost should be something very close to our target price of $35 per pack (plus shipping).


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## PGP (Apr 6, 2006)

*Re: Twice the Run Time and Brighter…*

Thanks for the update! I am glad you where able to get the washers in a smaller quantity!

Patrick


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## js (Apr 6, 2006)

*Re: Twice the Run Time and Brighter…*

PGP,

Yeah. Me too. Unfortunately, the $330 per 1000 of the one kind didn't translate into $33 or so for 100 of the other. The ones we ended up going with are going to be $85 for 100 of them, plus shipping. But they were never the sticking point. The positive nipple was the show stopper. Sinking $300 into a project for the good of CPF is one thing, but $3000 is quite another entirely. Although . . . come to think of it, I probably spent that much on developing the M6-R start to finish. Gosh. That's a fairly sobering thought.


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## SilverFox (Apr 9, 2006)

*Re: Twice the Run Time and Brighter…*

Update:

It looks like we are very close to going ahead on this project.

Jim and I had a long talk today and we realized that there are some additional costs we had not figured in. This means that the packs are going to be more expensive than we first thought, unless we get orders for 100 or so...

I would like to do a run of 50 packs, but will gage our run based on the interest generated in this thread. Several of you have already expressed interest, however we are going to need a few more people to get this project off the ground.

I think the price is going to be $38 per pack, but Jim is looking into getting some additional discounts. So let's consider that the top end of the price. If we can get them built cheaper, we will pass the savings on to you.

Shall we proceed with this? If so, how many packs do you want?

Tom


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## PGP (Apr 10, 2006)

*Re: Twice the Run Time and Brighter…*

I will definetly get one. If I have extra cash at the time money is collected I will get two.  

Patrick


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## NotRegulated (Apr 10, 2006)

*Re: Twice the Run Time and Brighter…*

I just found this thread and already I'm in...most likely for two.

I have an 8NX with about 4 B90 packs. I am one of the people who had to return the charger and batteries for replacements after about six months owning the light. I now have the charger that blinks green when the battery is fully charged. Two of my B90's work well but don't seem to hold a charge very long anymore. The other two B90's are brand new but untested. I think a couple of these battery packs you are making up would be great.

Being able to use the stock charger is a real plus. B90's already take 2 hrs to charge. These upgraded batteries would take about 3 hrs but you will get at least a half hour more runtime out of them.

On another note, my X80 bulb in my 8NX appears rather dim when compared to my P90 bulb in my 9P. The spec's show the lumen level about even. The bulb is the original with many hours of runtime on it. If this new battery pack could give me the brightness of my P90 bulb I would really be happy.


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## SilverFox (Apr 11, 2006)

*Re: Twice the Run Time and Brighter…*

Update,

I ordered the washers today.

Tom


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## bobbo (Apr 12, 2006)

*Re: Twice the Run Time and Brighter…*

Hi,
I will gladly order five of these batteries and "more" if they preform like I assume they will (hold a charge longer than 3 weeks).I presently have 3-8NX,2-8X,and 1 9N.SureFire had a bad run of the B-90 batteries several years ago and yes I have a few (18).SureFire replaced (15) B-90 batteries 7/04 for me.If I charge these batteries now,let them set for three weeks,they are only good for a few minutes when I use them!!?


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## glockboy (Apr 12, 2006)

*Re: Twice the Run Time and Brighter…*

I'm in.
Try to look at the 9v plug at electronic store, you can use it for the nipple for the battery pack.


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## hector (Apr 12, 2006)

*Re: Twice the Run Time and Brighter…*

In for one. Thanks for doing it.


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## HKocher (Apr 12, 2006)

I'm interested, I'm tired of having to change batteries on my 9AN in the middle of building searches...


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## Shark (Apr 13, 2006)

I was just wondering, can these batts be used in a Streamlight Stinger without the center nipple (+) soldered on? I dont use B90's in my 9AN any more I used to solder a 9V battery connector and a couple of small brass washers to to positive terminal on a stinger battery. But lately I have been using magnets on the Positive terminal on my stinger batterys for use in my 9AN and I use the same batterys in my stinger and my 9AN. I was just wondering if these packs will be in a similar configuration without the nipple soldered on.


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## SilverFox (Apr 13, 2006)

Hello Shark,

I believe that is correct. Jim was talking about using the prototype pack in a Stinger. I ended up having to utilize a magnet to use it in my 8NX.

Tom


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## Shark (Apr 15, 2006)

I would be interested in two of these packs.


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## NotRegulated (Apr 17, 2006)

Will you be taking orders on this thread or will you open a new one in the groupbuy section? Any estimated date for ordering?


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## SilverFox (Apr 17, 2006)

Hello NotRegulated,

I have you down for "most likely two..." 

We are getting the rest of the parts together and should have an update later this week.

Tom


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## sgt253 (Apr 17, 2006)

Gentlemen, I am glad I found this thread. These batteries are seemingly what I have been looking for to fill my 8nx Surefire. A question if I may. I have some b90's that will charge fully according to the charger indicator (flashing green led)when they are placed in the light, and not used for a day or two they die within 5-11 minutes. This doesnt seem right. Any opinions as to these cells would be appreciated. This was most disconcerting when I needed that light during my tour of duty. I have a couple (2) more that dont seem to do this. I definitely carry a primary cr123 light at all times, just in case.
Regards


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## SilverFox (Apr 17, 2006)

Hello Sgt,

It sounds like you have a bad cell in your pack. Are you able to measure the voltage of your pack? Fully charged it should be around 4.3 volts and fully discharged it should be around 3.5 volts or more.

Tom


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## Topper (Apr 17, 2006)

I would like one maybe 2.
Let me know Who How and When I need to pay.
Topper


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## nuggett (Apr 17, 2006)

I am interested in 1, maybe 2


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## 2dim (Apr 18, 2006)

My 8X was bought over 10 years ago...batteries never really worked right or for very long. Been through at least three B90 until finally giving up. Do you think if I called Surefire they would do something? Can anyone suggest someone in particular I could speak to, with a toll-free phone number if possible? Don't even know whether my older charger is functioning properly or would do these newer cells, but if so I'd certainly be interested in one...pending the response from Surefire.


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## SilverFox (Apr 18, 2006)

Hello 2dim,

SureFires phone numbers can be found on their web site.

10 year old battery packs are probably outside of the "normal" warranty, but you may be able to get a deal on the improved charger...

We know this replacement pack will work with the new charger, but are not sure about the older charger. 

Tom


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## sgt253 (Apr 18, 2006)

SilverFox, Thanks for the info. Measured two of four so far. One cell with a loose positive nipple functioned as advertised and measured within the specs you gave me. Another cell, seemingly fine, does not fully charge (no flashing green led on charger) and discharged in the light until just about dim measures 3.40. Will be checking out the other two cells. Probably will purchase a pack or two of the upgrade. Time will tell. Thanks.

Don


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## js (Apr 18, 2006)

*Re: Twice the Run Time and Brighter…*



glockboy said:


> I'm in.
> Try to look at the 9v plug at electronic store, you can use it for the nipple for the battery pack.



Glockboy,

If it were that simple, don't you think we would have figured it out right away?

No. A + snap terminal will not work. But that's OK, as we have a solution in hand. No need to look any farther. We are good to go.


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## T-Rex (Apr 21, 2006)

SilverFox said:


> I had no problems with fit in my 8NX, but we will have to check the inside diameter of the aluminum lights to make sure there is room.
> 
> Tom



Have you checked to see if it will work in an 8X?
The inside diameter of my 8X is 24.0 mm.

If it fits, I'll be in for 1.


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## europium (Apr 24, 2006)

*Will these packs fit in the L7, 8AX, & 9AN?*

Any word yet on what lights these battery packs will or will not fit into?

You only mention that it fits in the 8NX. Will it fit in an L7? An 8AX? In a 9AN?

The current model of the SureFire B90 rapid smart charger is the CN411. Is this the model of charger that you tested with your battery pack?

Is there any danger in regularly using your battery pack with the light constantly on (until it dims)?


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## SilverFox (Apr 25, 2006)

*Re: Will these packs fit in the L7, 8AX, & 9AN?*

Hello T-Rex,

I checked with Jim and he believes there should be no problems with fit in the 8NX.

Tom


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## SilverFox (Apr 25, 2006)

*Re: Will these packs fit in the L7, 8AX, & 9AN?*

Hello Europium,

We believe this will be a direct B90 replacement. Any light that uses the B90 will be able to use this battery pack.

I am using the CN411 (latest model) for charging and it works great. The early model has not been tested - yet. The latest model shows a red LED while charging, a green LED at the end of the rapid charge, and a flashing green LED at the end of the charge. I believe the older charger simply shows red and green, and does not go to flashing green. The chargers look the same, but the electronics are different in the new model.

There is no danger running the light continuously to the point of dimming. However, continuing to run the light after dimming may ruin the pack.

Tom


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## SilverFox (Apr 25, 2006)

*Re: Will these packs fit in the L7, 8AX, & 9AN?*

Update:

All the parts have been sent to your battery builder. We may have a couple of working prototype packs by next week.

Once we have the prototypes, a series of testing will be done to insure quality and we will be checking the fit in various lights. The batteries have already been tested, so this will be a check to make sure our production run performs the same as our hand made run. I will also try to find an old style charger to see if that will work.

When we are satisfied with the quality of the packs, I will begin filling orders.

Tom

When


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## wquiles (Apr 25, 2006)

Wouldn't it be awesome if there were enough space for a small over-discharge protection circuit that would fit within the length of the pack, similar to what PILA and AW's protected cells use for their LiIons (but of course designed for these cells/pack)?

Will


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## Topper (Apr 25, 2006)

We I looked at my charger and it is a CN400- not a 411 however it does start red go green and then blink green if I wait. I think I am OK with it if I am not someone needs to tell me please :candle: 
Topper


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## europium (Apr 25, 2006)

I believe I have found the data sheet for the GP 3700 NiMH batteries you will be using:

http://www.gpbatteries.com.hk/pic/370SCHR%20--%20ZRS5037%20rev1.pdf


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## SilverFox (Apr 25, 2006)

Hello Topper,

The whole kit is called the CN411. It is made up of an AC transformer, a DC adapter and the CN400 cradle.

My cradle has CN400 on it as well.

Tom


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## Topper (Apr 25, 2006)

Thanks Tom, I feel more better now  
Topper


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## europium (Apr 27, 2006)

If these battery packs will work fine with each of the two bulbs in the Surefire 9AN, then I am in for three. :thanks:


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## glockboy (May 3, 2006)




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## js (May 4, 2006)

Hi everyone!

I got an email from our battery pack maker yesterday. He was sort of finished with the sample packs, BUT his shrink wrap that he had ordered was a bit too large and wasn't doing a nice neat job at wrapping around the bottom of the stack. So we confered on shrink wrap sizes and about the fact that the wrap at the TOP of the pack should NOT wrap over, but should be flush, and so on. And a bit later he informed me that he had more on the way from a supplier in the same state as him.

So, the salient point here is that SilverFox should have the sample packs very soon--like a week maybe. And we can go from there.


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## maverick (May 13, 2006)

I would love one of these packs.... but is it too late to order?


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## SilverFox (May 13, 2006)

Hello Maverick,

It is not to late to get on board.

I just heard that the prototype is on its way to me to check out. There was some mention of difficulties with the + nipple, but we will see what was finally worked out.

I'll let everyone know when it gets here.

Tom


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## maverick (May 13, 2006)

Hi Tom, thanks for heads up. I will be interested in 1 battery when available.


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## js (May 14, 2006)

Actually Tom, he sent the packs to *me* by accident, even though he was instructed to send them to you. No problem though. I'll get a chance to check them out first hand this way--although I don't have a SF rechargeable to test them in--then I'll send them right out to you for *real* testing.

He said he wasn't happy with the + nipple just because the weld joints weren't pretty and were showing. Who cares? It won't affect anything I don't imagine. But we shall see.


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## js (May 16, 2006)

Got the packs today.

They look good. In fact, they look very good. I will send them on to SilverFox tomorrow.

A few notes:

The idea for the negative ring and connections worked perfectly--better than I had hoped, in fact, and despite our battery pack makers concern, the positive nipple construction also worked out great. The only issue is that it doesn't LOOK absolutely aesthetically perfect. The weld joints look a little rough, or large. But that is a total non-issue. The nipple is almost a perfect match to the original SF B90 nipple, and it is welded on very securely to the battery, and, most importantly, the critical height difference between the top of the negative ring and the top of the positive nipple is EXACTLY the same as on a B90.

And the overall build quality of the packs is very good, and it has a nice yellow shrink wrap on it. 

There is only one possible problem that could arise. The GP3700's are longer than the cells used in the B90 (and fatter, too), and the overall length from the top of the positive nipple to the bottom of the pack *may* be just a bit too long to fit into the plastic charging cradle. SilverFox and I were talking on the phone about it and measuring things and he thinks that the pack will probably squeeze in.

Let's hope so. Failing this, we can try to shorten the positive nipple just a touch, which will make the negative to positive height difference less than OEM, but should still be close enough to spec to work just fine. Failing THAT and we're pretty much screwed! 

j/k. Failing that and we have to investigate different cells. So let's all just keep our fingers crossed and hope for the best.

I was going to post pictures, but I ran out of motivation. Tom can do that.


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## eltel999 (May 16, 2006)

Hi,

I really hope this project is working out...

If the battery packs fit the SF Charger and there are any available, please count me in for one

My 9AN is in desperate need of some extended runtime!


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## Topper (May 17, 2006)

Yes indeed. Fitting both the charger and a 9AN is a must for me but I am fairly certain they will work it out. I hope you guys have a 9AN to try it in.
If not feel free to send me a proto to try in mine, I have the Turbo Head as well and willing to try one to check that scary too much juice flash pop stuff.
(I know weak attempt to get to the head of the line)  
Topper


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## js (May 17, 2006)

Topper,

We will indeed be sending someone with a 9AN a pre-production sample to check fit. We will know for sure *BEFORE* Tom takes any money. No worries.


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## Topper (May 17, 2006)

I'm your Huckelberry, if you need one. And send it back or pay for it however you want.
Topper


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## js (May 18, 2006)

OK. So, I had a little free time today and I uploaded a couple pics to my server space.

Here is a closeup of the top of our GP3700 B90 bad boy battery:







You can see two of the three ribbons that run from the underside of the negative washer-ring down to the negative casing of the bottom battery in the stack. The third ribbon is hidden in this photo but runs down the pack just like the other two. The reason for three? Simple: they keep the negative washer centered on top of the battery stack, as they are equally spaced around the circle. Normally, on a B90 or Stinger pack, the top negative ring is actually the top of a *collar* that fits down over the top of the pack, with a plastic insulating washer underneath it. However, the GP3700's are too fat to fit inside that hardware. Plus, it is expensive to get in small quantity. AND, on top of all that, I feel that this is actually a superior solution and is a higher quality construction method. Our battery pack builder acutally uses a few dabs of hot glue underneath the washer to keep it in place while he bends the ribbons down the sides and welds them, but the ribbons alone would be enough to hold the ring centered, and are what provide the real strength should a lot of force be applied to the side of the washer.

The negative washer ring is insulted from the top negative casing by the top cells own shrink wrap (which is left on), and the black fiber washer underneath of that. So a plastic insulting washer is unnecessary, and in our case, would have been an added expense and would have offset the height differential between top of negative washer and positive nipple.

Check out the positive nipple and welds. You can see that the welds aren't going to win any beauty contests! Nonetheless, they are solid and well made and that nipple is on there to stay. The nipple is also an almost perfect reproduction of the SF B90 nipple, right down to the dimple in the top (which is made by hand, BTW). And once the battery pack is in the light, you won't see those welds anyway. :devil:

OK. And here is a full picture of the whole pack:






And it's not a black shrink wrap, which will make Tom happy. I've never seen anyone freak out so badly about shrink wrap color as Tom did when he got the proto-type hand soldered packs from me! Geesh. You'd think he'd be thankful to be getting them at all and not complaining about the stupid color of the over wrap. Don't ever send Tom a black wrapped battery, man. He'll just about bite your head off and you'll never here the end of it. ( :devil: I'm joking of course, although Tom doesn't like black shrink wrap--he can't deface the packs with magical markers if they're already black! LOL!)


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## Bullzeyebill (May 19, 2006)

I would be interested in one depending on price.

Bill


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## SilverFox (May 20, 2006)

Hello Bill,

We are still thinking that we can offer the packs for $38 each.

Tom


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## SilverFox (May 20, 2006)

Update:

I received the prototypes today. 

We have a few problems to work out.

The overall diameter makes the fit a bit snug. We think we can take care of that without too much of an effort.

The pack just barely fits into the stock charger. This is going to take a bit more effort. I have talked with both Jim and our pack assembler and feel that we have some options available. Jim mentioned checking out other cells, but I have been very pleased with the performance of the GP cells and don't want to change, unless there is no other way to go. I would like it to snap into the charger with minimal effort. It now takes quite a bit of effort.

Once we get over these hurdles, we will be good to go.

Stay tuned...

Tom


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## Cleron (May 25, 2006)

Just found this thread & thought id give it a "bump". Im in for say 2 packs when you guys get this sorted out. I'd like to know if there are any ill effects on the low output bulb though.


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## SilverFox (May 25, 2006)

Update:

I have sent the batteries back to the pack builder along with my 8NX and charger. We have been discussing the various problems, and he believes he can get a handle on all of them.

It seems that with the nipple set to the same dimensions as the stock pack, the battery barely fits into the charger. I have worked out a minimum nipple length and we are going to see how that works out. 

The pack will not fit into my light with 3 layers of shrink wrap. We are working on ways to eliminate at least one layer, as well as some other things to reduce the diameter of the pack.

Stay tuned...

Tom


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## js (May 25, 2006)

Cleron,

No ill effects to the bulb. As it is, the lamp is very under-driven with the stock battery. With the GP3700's it merely comes up to something reasonable, like the rest of the surefire incan lamps: 35-45 hours of life.


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## dano (May 25, 2006)

I used to make custom hi-cap NiMH packs for Stingers and SF's.

For the SF positive nipple, I used the smaller nipple from a 9 volt battery connector.

For the ribbon/negative ring, I used recycled pieces from old packs (maninly scavanged from co workers).

The latest Sub-C hi cap cells are 4700MAH, which would be a great power source for some people's applications. For my Stingers, though, I've gone back to the stock stick, as I never used the full capacity of a hi-cap battery stick.

These sticks sound good.

--dan


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## js (May 25, 2006)

Dano,

We can't salvage the hardware, because the GP3700 cells are too large in diameter to fit the old hardware (or equivalent new hardware).

For the positive nipple, the 9 volt connector is too short for proper height delta--however, now that we actually need to go away from that, it may be worth checking out. However, it is also not quite the right diameter either.

As for the higher capacity sub-C's, no go. The length and diameter problems we are having now are totally due to the LENGTH and DIAMETER of the Gold Peak 3700 cells being greater (in both) than the stock SF B90 cells.

The IB4200 and the like type sub-C's are *even larger* than the Gold Peak 3700's. That's how these companies cheat and come up with a "higher capacity" cell. They simply make it larger. Then the other companies have to compete so they bump up the size as well. And pretty soon, you've totally crapped all over the sub-C standardized size numbers. Which is pretty damn stupid if you ask me. People should be able to tell the difference between an *actual* increase in capacity versus a simple size increase. Hell, why don't we just label some D cells as "sub-C" 's and advertise a 9000 mAh sub-C? It's the same thing, only taken to the absurd.

Anyway, the fit problems we have will be solved in four ways:

thinner Nickel ribbon: our supplier is using 10 mil ribbon, because he generally rebuilds power tool battery packs, which can draw 10 or 20 amps no problem. So he needs the extra beefy nickel ribbon. We do not.

narrower nickel ribbon: our supplier is actually cutting down wider nickel ribbon (and still ending up with wider than necessary ribbon) in order to create the ribbons for our packs. So if he buys 5 mil, 1/8" ribbon, this will help significantly both because of the thinner size and because it won't have any tipped up or turned out edges to add thickness to the diameter.

thinner shrink wrap: he is currently using fairly thick shrink wrap, and two layers of it, plus the wrap on the cells. Even just going to a thinner wrap will probably be plenty of difference to ensure a free-fitting pack.

shorter positive nipple: no problem to shorten the nipple we are currently using, and while I don't like to change the negative ring to positive nipple height delta, it will probably be fine--field testing will tell.

If these things don't fix the situation, then we will simply have to look into alternative cells.

Stay tuned.


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## depusm12 (May 25, 2006)

Sounds good if the problems can be worked out. I would be in for at least 2 maybe 3.


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## W4DIZ (May 29, 2006)

depusm12 said:


> Sounds good if the problems can be worked out. I would be in for at least 2 maybe 3.


Me too.


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## N162E (May 29, 2006)

I have a VERY early 9N, ID of light is .944 current battery purchased 03/03 is .900-.912. I also have a very early quick charger and a CBA and would be willing to put the battery through its paces. I am in for 2.


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## SilverFox (May 29, 2006)

Hello Fred,

Thanks, I just passed that information on to our pack builder. I have sent him my 8NX along with the SureFire charger. I was also thinking about sending along a shoe horn, but didn't... 

Tom


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## cnjl3 (Jun 3, 2006)




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## MrWonderful1961 (Jun 13, 2006)

Please put me down for one as well. My 9N charger has a '93 copyright date on the circuit board so I can let you know how well it tops off the new pack once I get it.

As an aside, it's kind of funny, but I've had nothing but trouble with my charger keeping it's connection to the wall wart that came with it. I'd have to set the charger on top of the cord and pull it tight and not breath while leaving it to charge. I finally broke-down last night and desoldered the coaxial socket and replaced it with an 8-inch pigtail and Anderson PowerPoles.

It only took me a little over 10 years to fix that annoyance... I guess I really could stand to be a bit more laid-back about such things. :lolsign: 

Has anyone else had similar experience with a 9N charger? My light's S/N is 106123, circa '94-'95, IIRC.

Sorry for the OT rambling... 

Thanks, guys, for a great opportunity to resurrect an old friend with some new and improved runtime AND output! :goodjob: 

Jim


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## Lodogg2221 (Jul 2, 2006)

Hey, if this is still in the works, I may be in for a few. I have a 9AN already that seems to burn thru the batterys...and an 8AX on the way, so probably 2 for sure, maybe more.


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## SilverFox (Jul 2, 2006)

Update:

This project is still on.

We are exploring a problem that occurred during testing. We had a pack vent during charging. It was not formed prior to use, and we think it was out of balance, but we are checking out the possibility of a defective cell, among other things.

I am out of town right now, but plan to continue the testing when I get back.

Stay tuned...

Tom


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## monkeyboy (Jul 9, 2006)

This is a great idea. One of the reasons I won't get a surefire L7 is the crappy battery capacity for the size.

why not use 4300 GP cells? according to the spec sheet, they are the same size as the 3700s. Or is this a lie?

3700 spec sheet:
http://www.gpbatteries.com.hk/pic/370SCHR%20--%20ZRS5037%20rev1.pdf
4300 spec sheet:
http://www.gpbatteries.com.hk/pic/430SCHR-ZRS5050rev2.pdf


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## SilverFox (Jul 9, 2006)

Hello Monkeyboy,

I have not seen the 4300 cells. I will pass this information on to Jim and we may get some and check them out.

Thanks.

Tom


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## monkeyboy (Jul 9, 2006)

I see them for sale here:

http://www.battlepack.com/loosecells.asp

It is possible of course, that the cells are slightly larger than the specifications indicate although those measurements on the spec sheet seem to have very tight tolerances. Lets hope they are the same size as the 3700


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## js (Jul 18, 2006)

Tom,

Are you back from the Wildlands yet? And if not, when?


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## monkeyboy (Jul 19, 2006)

OK, I finally took the plunge and bought a Surefire L7. Arrived today  Haven't had a chance to try it out properly yet but I'll post a review if I have time. 

Put me down for two batteries

Thanks
Any more updates on the project?


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## SilverFox (Jul 19, 2006)

Update:

I have the prototype packs in hand, along with my charger and am begining to run a series of tests on them.

Tom


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## PGP (Jul 24, 2006)

How are the test going!  

Patrick


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## SilverFox (Jul 24, 2006)

Hello Patrick,

Fine... We had one pack vent and I believe it did that because it was not formed prior to charging. I am exploring charging the packs on the stock SureFire charger.

Tom


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## milkyspit (Jul 25, 2006)

Following with great interest.


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## SilverFox (Jul 29, 2006)

Update:

After running several cycles on my charger I decided to do a run time test in my light. 93 minutes. I expect this to improve slightly with a few more cycles.

I did notice that my SureFire charger's green LED light stopped working. I pulled the two screws out of the back of the charger to see if I could see anything. WOW, there is a two position switch that says NiCd and NiMh...

I am going to give the NiMh setting a try.

Any one else notice this switch?

Tom


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## monkeyboy (Jul 30, 2006)

nope, no switch on mine. But the word NiMH and NiCd are written on the circuit board.







Mine is a new style charger too (green light flashes)

Silverfox, did you manage to get hold of those 4300s?


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## SilverFox (Jul 30, 2006)

Hello Monkeyboy,

Interesting... They must have decided not to keep the switch.

I have had a very busy summer and have not had a chance to check out the 4300 cells. Our prototype packs are snug, so we may be checking out some different cells.

Tom


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## Lodogg2221 (Aug 5, 2006)

I dont have that switch in either of mine. One is an older new style with a larger chip than the one pictured, and the other is brand new, and looks exactly like the picture inside. 

Any new updates? I know its only been a week, but I only get to check my email on the weekends usually, so I had to ask!


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## SilverFox (Aug 5, 2006)

Hello Lodogg,

Welcome to CPF.

I talked with SureFire and they were surprised that my unit had a switch. I must have a very early unit.

I am satisfied that the prototype packs are working properly. I will be moving to field tests to make sure. I discovered that my 8NX body is tapered. the pack slides in smoothly about 2/3 of the way, then becomes a bit snug. When I turn the body upside down, the pack will not slide out without shaking it a little.

I am going to have to try it with an aluminum body to see if we have a clearance problem.

Hot off the charger I am getting 90+ minutes and if I let them sit for a day I am getting 80+ minutes on my 8NX.

We have a few more details to work out. The pack is a tight fit in the charger and I am looking to see if that can be improved. If it fits in the aluminum bodies and if the field tests don't turn up any problems, we should be good to go.

Tom


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## PGP (Aug 5, 2006)

Glad to hear things are moving along! :goodjob: 
Do you have a 9AN to check for fitment issues!

Patrick


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## SilverFox (Aug 5, 2006)

Hello Patrick,

Topper has offered to check out a prototype pack in his 9AN. What I am looking for is someone with an 8AX to make sure the pack will fit.

Tom


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## dano (Aug 5, 2006)

Hey, I have an older 8AX that could be used, if it's still needed.

-dan


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## Topper (Aug 5, 2006)

Gee Dano, was that an offer to send it to Tom? Now I feel bad for wanting Tom to send the cell to me to try in my 9AN. So Tom Sir, I will send my 9AN with the Turbo Head instead of you sending the proto cell to me. That way you can check it out (yes that sounds lazy) and send the light back when your happy with the cell. Tom please PM your addy and I will send it your way with both the standard head and Turbohead.
Topper


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## SilverFox (Aug 7, 2006)

Hello Topper,

Thanks for the offer, but I will send you the prototype battery pack. I am interested in seeing if it fits the light and will properly charge on your charger.

I should add that you may want to lay the charger on its side and have a spill resistant surface to charge on, just in case it tries to vent. Also, you should monitor the temperature during the first charge. Nothing fancy, just touch it from time to time to make sure it is not getting too hot.

Tom


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## SilverFox (Aug 10, 2006)

Update:

Prototype packs have been sent out for field testing.

They seem to be a bit snug in the aluminum lights, but still fit. Talking with Jim has revealed that we can go from 5 mil ribbon strips to 3 mil strips and still handle the current demands. This should be enough to address the "snug" problems.

The packs are also a tight fit in the charger. I am not sure we can do anything about that, but the 3 mil ribbon should help with that as well.

Tom


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## Nam (Aug 11, 2006)

Hi Tom,

Thanks for the link. I just got off the phone with Surefire after reading through this thread. Eric in customer service told me I had two bad batteries, and is sending out two new ones. He knew it from the serial numbers on the sticks. 

My charger says CN400 on the back, and T210 on the wall wart. Eric seemed to think it is the same as the latest charger with the exception of the blinking light, but I have no clue if that's correct or not. It says "LPC 12415 REV A" on the circuit card. If your packs will work with it, let me know. Even though I'm getting two new cells from surefire, I might be in for one of yours once the testing is done.

Thanks,

Todd


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## SilverFox (Aug 14, 2006)

Update:

Monkeyboy mentioned the GP 4300 mAh cells earlier. I have been able to verify that they are the same size as the 3700 cells. 

The 4300 cells do cost more ($9.99 vs $7.49), and I do not have any idea of how well they will perform or hold up. 

We are targeting $38 for the 3700 pack, is there any interest in paying roughly $6 more for a 4300 pack?

Tom


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## MSI (Aug 14, 2006)

Tom, battlepack.com sells IB4200 cells for $5.85.

Edit: IB4200 are probably too fat to use.


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## monkeyboy (Aug 14, 2006)

Hey, this is good news  

I'm certainly prepared to pay $6 more for the 4300 battery pack but you probably already knew that. The cost per mAh is about the same, which I think is a better way of looking at it. I'd expect most SF owners would be prepared to pay a bit more for the 4300s.


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## SilverFox (Aug 14, 2006)

Hello MSI,

Yes, the IB4200 cells are too big.

Tom


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## SilverFox (Aug 16, 2006)

Update:

I have a sample of the GP 4300 mAh cells coming. I will get a prototype made and see how well it performs.

Tom


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## SilverFox (Aug 17, 2006)

Update:

I am trying the prototype pack in an 8AX. It fits.

It seems that the Aluminum body is a little bigger than the Nitrolon body.

The pack seems a little long... So does the B90 pack. 

I have to back the head off so that most of the "O" ring is showing to shut it off.

Anyone else have an 8AX? When you shut your light off, how much "O" ring is showing?

Tom


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## lm4300 (Aug 18, 2006)

If this helps, I have an 8NX (Nitrolon) and if I twist it just to the point where the light turns off, I still can turn the body about 3 full revolutions before the O ring shows, and at that point, the head is basically completely unthreaded.


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## SilverFox (Aug 18, 2006)

Hello Lm4300,

My 8NX does the same...

I called SurfeFire and they said that there was no lock out for the 8AX. The work around is to remove the foam washer at the bottom of the battery tube, then install and additional "O" ring just under the threads. I still have to back the body out to almost completely expose the stock "O" ring, but the additional "O" ring holds things tight and offers some degree of water resistance.

Please note that the 8AX functions normally when it is screwed down to cover the stock "O" ring, it is just that I like to back the body off until I have a little rattle of the battery pack inside the light when I am packing it for travel. With the 8NX, I stand the light on the tail end on a counter (pressing down on the switch) and back the head off until the lamp no longer lights. This means that the light has to be pressed against something pretty hard to get it to light during travel.

With the stock 8AX and without the additional "O" ring, I would be tempted to remove the battery pack for travel.

Testing is continuing with the 8AX and a charger that is functioning normally.

Tom


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## SilverFox (Aug 19, 2006)

I have run into another obstacle with this project...

Topper has one of the prototype packs and has reported that sometimes he is getting reduced run times. They are still more than the stock B90 pack, but not as high as they should be.

I just had this happen to me. 

The normal B90 pack is giving me around 50 minutes of run time in the 8AX. I charge the B90 pack until I get a blinking green LED. Last night I did the same thing with the GP 3700 pack and only got 72 minutes.

I put the GP 3700 pack on the charger last night and had a blinking green LED this morning. I checked the voltage of the pack and noticed it was at 1.38 volts per cell. That seemed a little low, so I removed the battery pack and put it in to charge again. When I do this with the B90 pack, it will go from red to green LED in around 5-10 minutes. I was surprised to observed that the GP 3700 pack took 50 minutes to go from red to green, and an additional 90 minutes to go from green to blinking green. 

This would suggest that SureFire has incorporated some sort of timing device in the charging circuit that limits the bulk charge.

My "older" new style charger does not do this, but the latest new style charger seems to limit the time the charger is fully charging. 

This would seem to indicate that in order to get the full capacity from a pack that was completely drained, you would have to do a double charge. When the LED turns green, pull the battery out and stick it back in again, or do the same thing about 1 hour into the charge cycle.

We will continue the testing and I will have Topper try this and see what happens.

By the way, the fully charge GP 3700 pack gave me around 95 minutes of run time in the 8AX.

When Jim Sexton and I started on this project, we wanted improved run time (we have this), better light quality through improved midpoint voltage (we also have this), a direct drop in without modification to the flashlight (our prototype packs are a little snug, but we have a solution to fix this), and we wanted to utilize the standard charger. 

It appears that we are going to fail on our last design requirement... The standard charger can be used, but it is not "seamless." Going to the GP 4300 cells (if they turn out to actually be the same size) should not have any impact on this problem, however you may only get 72 minutes on a single charge.

Comments?
Opinions?
Discussion?

Tom


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## js (Aug 19, 2006)

Tom,

Interesting. As you suspected, eh? (I was on the phone w/Tom when this happened, actually  ). Well, it could be worse. The fact that you CAN use the standard charger at all, even if you have to double charge, is still a pretty cool bonus. Given the change of chemistry, I remember that we were doubting that the stock charger would even terminate charge properly. So I wouldn't say we "failed". Not entirely anyway.

It may be possible to mod the circuitry to have a different time out. I know on the MAX712/713 chips, this is set by tying two pins to certain other pins on the chip, or even leaving one or more of them open. This is obviously not ideal, not a "drop-in" solution, but still. If it were easy to do, we could do a bunch of them at once, and this *probably* wouldn't hurt with standard B90 packs, as the detection would shut off fast charge at the appropriate time--although we would want to test this to make sure.

Anyway, those are my thoughts, FWIW.


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## SilverFox (Aug 20, 2006)

Hello Jim,

Thanks for your insight. I am not sure I want to get into modifying the stock charger, but it is something to consider.

I ran a test last night. I charged the Prototype pack until the green light came on, then pulled the pack and put it back in again. The run time test gave me 95 minutes which is what we are hoping for from this pack.

I think I need to do a test where I do a single charge and leave the pack to trickle charge for an extended period of time to see if the trickle charge will bring the pack up to full charge. I know that an overnight trickle charge will not do it, but perhaps a couple of days...

Tom


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## T-Rex (Aug 21, 2006)

My 2 cents:
The initial charge tops out ~72 minutes. That's still 22 minutes above stock. If I get to the battery, I can reset the charger and get another 23 minutes. 

Sooo, if I'm lazy, I get a 44% increase. If I spend 30 seconds to reset the charger, I'll get 90% increase over stock. More run time which would cost me 30 seconds. Even better, put the charger on a 4 hr timer and have it cycle on/off.

I'm still in since I don't see the downside.

I agree with Tom. Given the complications that could occur, I don't want to be messing with the charger if another solution is much less painful.



SilverFox said:


> I have run into another obstacle with this project
> 
> ...
> 
> ...


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## wptski (Aug 21, 2006)

Tom:

Maybe you ought to forget using the original chargers, go to a wallwart the puts out 9VDC at a low millamps and go for a allnighter?

Make that a 6VDC.


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## Topper (Aug 21, 2006)

Tom, do want me to pull it off on a solid green? Or wait till it blinks then pull it for a second and recharge or does it matter?
Topper


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## SilverFox (Aug 21, 2006)

Hello Topper,

Keeping in mind that we are using a NiCd charger to charge a NiMh battery pack, I have done some additional testing. This is not the best set up, but it works very well. We are not supposed to charge NiMh packs on a NiCd charger because the NiCd charger will overcharge the NiMh battery pack. This overcharge can cause the NiMh pack to vent if it gets very hot.

Jim and I were surprised that we were able to charge the NiMh pack on the NiCd charger, then I discovered the NiMh/NiCd switch on my charger. We speculated that SureFire had gone to a NiMh charge algorithm to keep from having additional problems with the B90 battery pack. We may have been fooled into this thinking and SureFire may have put a time limit on the bulk charge instead. Since our batteries are higher capacities, we time out before venting. I will have to set up a data logger to see if I can figure out what is going on.

In the meantime, I put a pack on the charger and left it for an additional 12 hours after the blinking green light came on. Just finished a discharge test and got 94 minutes of runtime. The pack peaked at 4.280 volts which gives us around 1.42 volts per cell.

This is an ideal way to charge and will result in a very long cycle life. A rapid bulk charge, followed with a lower rate charge, finally topped off by an extended trickle charge should fully charge the cells as well as balance the pack. The pack may warm up during the initial bulk charge, but it should stay cool during the rest of the charge cycle.

The only caution would be if you only used the light for 5 or 10 minutes, then put it back on the charger to top it off. I have not checked this out, but will do some additional runs to see what happens.

OK Topper, sorry for being so long winded, but back to your question...

1. If you need the light right away and the pack is dead, charge it until the green light comes on and use it.

2. If you have a little extra time, charge the pack up until the green light starts to blink then use it. This should give you around 70+ minutes in an 8NX or 8AX. Your 9AN run time will be lower because it has a higher current draw. I am observing that it is taking around 90 minutes to go from solid green to blinking green.

3. If you need the maximum run time, charge the pack up until the green light turns on, then you have two options. If time is pressing, pull the pack and put it back in. When the green light starts to blink after the second charge the pack should be fully charged. Or you can leave the pack on the charger with the green light blinking for around 12 hours and let it trickle charge to full charge.

Option 3 is the easiest on the battery pack, but takes the most time.

Let us know what works for you.

Tom


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## lm4300 (Aug 21, 2006)

What about those with the Gen 1 chargers. I took the back off mine and saw no switch, and I've never seen it blink green. 

What do you recommend? Once the batteries are available, would getting a new charger be the best way to get the most life out of them?


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## SilverFox (Aug 21, 2006)

Hello Lm4300,

I believe, but have not tested, that the older style SureFire B90 chargers will cook this NiMh pack and cause it to vent. The new style charger (blinking green LED after a solid green LED) is the one you want.

Tom


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## Topper (Aug 21, 2006)

Hi Tom, I tried pulling it for a few seconds after it turned green placed it back and waited a long time before it started to blink. I noticed it was a little warm but far from hot so I figured it was good. It ran 16 seconds and my main lamp died. It did not blow up just died and I thought "Dang maybe that was not a good idea after all" then after pouting abit and mourning for a costly lamp two things dawned on me.
The 20 lumen lamp did not fail and only the Lord knows how many hours I had on that lamp before I started testing this prototype. I located a spare N90 and got 62 minutes run on the cell. That was much better than other runs with my 9AN I would guesstimate I have around 30 or so runs on this pack and the lamp that died was in the light for maybe 2 years before starting this test so I think it was just coincidence.
Topper


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## cnjl3 (Aug 22, 2006)

My surefire charger is so old that the instructions that came with it said just to charge it about 12 hours and then unplug it (a timer solved that problem) - initially i thought i would just order a new surefire charger but instead i will probably use my MAHA charger or my Triton charger for your new improved NIMH battery pack (90+ mins of lumens!!!! WOW!) - wouldnt a modern charger solve everyones charging problems??? Both of my chargers will handle all Nicad, Nimh & li-ions. 
Dont get me wrong i love my surefire light- i just have never been that crazy about the charger that came with it.


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## SilverFox (Aug 22, 2006)

Hello Topper,

I am sorry to hear that your lamp died, but it sounds like it had a good life...

What kind of run time do you get with the stock B90 pack?

Tom


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## SilverFox (Aug 22, 2006)

Hello Cnjl3,

The improved battery pack will charge up just fine on any NiMh pack charger. I have been cycling my pack on my Schulze to "break it in."

The reason we are trying to get the pack to work with the SureFire charger is because everyone who has a light that uses the B90 battery pack already has a charger for it. Jim and I wanted to offer an upgrade that did not require anything but a battery change.

If you have a pack charger, I would recommend using it. We are just trying to get it to work with the stock charger so people do not have to go out and buy another charger.

Tom


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## cnjl3 (Aug 22, 2006)

Thanks Tom!

I had already made my own home made "B90" packs i currently
have two of them --but i will probably want at least two of yours.

CYL


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## SilverFox (Aug 22, 2006)

Update:

The testing continues...

SureFire advertises about 50 minute run time for the 8AX, and the B90 pack should re-charge in about 2 hours. I took a prototype pack and in 2 hours the light had turned green, but was not to blinking green. I did a run time test and got 55 minutes.

So, if you only charge until the green light comes on (about 2 hours), you will still have better run time than the B90 pack.

Tom


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## Topper (Aug 22, 2006)

Hi Tom, 
I have two B90's in use and on a runtime test I got 32 minutes on one and 29 on the other. I tried the "trickle for hours" and got 57 Minutes on the "proto pack". That is real close to 62 minutes on the first try at a reset after turning green. So I think? things are looking good and I will make an attempt at keeping up with the time on this N90 lamp. It has 2 hours on it give or take and I have a second "back up" to this lamp (this was my back up lamp) so I will do what I can as "testing" goes and would prefer this to work out in the long run without me buying another charger  
Topper


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## SilverFox (Aug 22, 2006)

Hello Topper,

Thanks for the information.

It looks like the 9AN will run for around 30 minutes on a stock B90 pack and 50+ minutes on the NiMh pack. With the 8NX and 8AX I am getting around 45+ minutes on the stock B90 pack and around 90+ minutes on the NiMh pack.

I just finished testing a double charge. It took 4 hours to go from red to green, two times. Hot off the charger I got 95 minutes of run time with the 8AX.

I think we can hold off on further testing for now. The pack seems to be doing what we want it to do. I am a little nervous about the double charge, but my pack only got warm, so it might be OK.

I still have not received the 4300 cells. I will do some additional testing once we have those made into packs and then we will be ready to start taking orders...

Tom


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## Topper (Aug 22, 2006)

Hi Tom, PM sent.
Topper


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## js (Aug 22, 2006)

Tom,

Good news. Good to hear. As you say, it's ideal in some ways to do the charge to trickle, and then leave it for 12 more hours. Nice and easy on the batteries, that's for sure. In fact, I bet that trickle rate is so low, it would be reasonable to leave the battery in the charger for days and days at a time (but not weeks and weeks). And the single or double charge are both still fine options, really.

I look forward to what happens with the 3 mil ribbon and 4300 cells!


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## europium (Aug 22, 2006)

I am going to withdraw my offer to purchase 3 battery packs. There have been a number of problems, none of which alone is too substantial, but I feel that this new battery pack solution falls a bit short of my expectations.

I think it is a worthwhile project and I wish you success. 

I am left thinking that: 

(a) Surefire itself should solve this 'problem' of short runtime by offering a NiMH battery upgrade + a new improved multi-chemistry charger for its stock B90 rechargeable lights, 

(b) It is long past time for Surefire to join the 21st century by offering Li-Ion rechargeable lights with both better outputs and longer runtimes than their current rechargeable lights, & 

(c) Surefire should also upgrade stock incandescent lamp assemblies to produce better, whiter output with the same expected lifetime so as to compete with 3rd party LA offerings which are not only better but cheaper than what Surefire now sells.

Just my 2 cents.

Eu


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## SilverFox (Aug 23, 2006)

Hello Eu,

No problem at all.

Developing a new product is not without its pitfalls. I have been very vocal about the process we have been going through so people can make an informed decision.

If I may take a moment and comment on your "thinking..."

(a) SureFire is interested in this project, however there are a few obstacles to overcome. They have a stock pile of NiCd cells, it costs money to re-design a charger, NiCd chemistry is less effected by heat and cold, NiCd chemistry has a lower (but not by much) self discharge rate, NiCd chemistry can tolerate extended times of trickle charge better, lower capacity NiCd cells may be able to handle physical abuse (through dropping and recoil loads) better than higher capacity NiMh cells, the lower capacity NiCd cells have a higher cycle life than the higher capacity NiMh cells, and we have to realize that not every SureFire flashlight owner is using the B90 battery pack.

I am steadily chipping away at all of these obstacles, however I am not sure there is anything I can do to improve the sales of lights that utilize the B90 battery pack. Fortunately there is enough interest to do a limited run, but I don't think there is enough interest for a full blown production run. 

(b) I think SureFire should skip Li-Ion completely and move on to the Li-"safe" cells that will not rapidly vent with flames when abused. Li-Ion cells can malfunction when subjected to physical abuse (when dropped or exposed to recoil loads). Unfortunately these safer cells are larger in diameter and I am not sure SureFire is ready to re-design their product line.

(c) I think the design of the SureFire lamps is very good. A problem occurs when the battery pack can not maintain voltage under load. In those conditions, the lamps "whiteness" is diminished. The NiMh replacement pack not only will offer extended run time, but it also holds the voltage better under load resulting in a whiter beam.

Tom


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## js (Aug 23, 2006)

europium,

Glad you have reached clarity and made a decision even before the final proto-types have been made, let alone the first production run samples.

Impressive! You aren't psychic are you?


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## SilverFox (Aug 23, 2006)

Update:

The 4300 and 4400 cells have arrived. I will put them through some cycle testing and then send them to be assembled into packs. More prototype testing to follow.

Tom


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## lm4300 (Aug 23, 2006)

A new B90 charger from SF is $67.00!! Where can I get one cheaper?!


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## SilverFox (Aug 24, 2006)

Hello Lm4300,

I just got one for free...  Well not quite as good a deal as it sounds. I was looking for an 8AX. SureFire lists these lights for $140 by themselves. If you want the charger and a couple of B90 battery packs the price goes up to $207.

I was browsing buy sell and trade and found that Oldgrampajack had a complete 8AX package (including charger) for $139.95 including shipping. As you can see, I got the charger for free.

I would contact SureFire and see if they will sell you only the battery holder for the charger. You should not need a new power supply, and the charger is in the battery holder. They don't list that separately, but it doesn't hurt to check with them.

Tom


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## Topper (Aug 30, 2006)

I tried something "new" so I thought I would post about it. I allowed the proto pack to charge and left it to blink for at least 12 hours then pulled it and left it to sit 72 to 80 hours (trying to see how it holds the charge).
I still got 54 minutes runtime. After talking with Tom and reading his and js's posts on this thread I have been getting 58-62 minutes every time after letting it blink for at least 12 hours. 
That looks good to me.
Topper


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## SilverFox (Aug 30, 2006)

Hello Topper,

That is good news. The prototype pack seems to be holding up well.

A general update:

I have been cycling the 4300 cells for the past few days and they are performing very well. The 3700 cells did not quite give us twice the run time. It was close, but not quite. If the 4300 cells work out, we will definitely have twice the run time. 

I have sent the cells off to have them made into prototype packs. We are incorporating the final changes to the design and if everything works out, we will be ready for the first run of packs ready for sale. By then I should have a price worked out as well.

I will be out of town for awhile and will be doing a lot of testing on the prototypes I have. I am interested in how the packs hold up to field conditions. The purpose of this testing is to see how well the packs are constructed. If I drop my light, I want the battery pack to hold together. I will also be checking cooler weather performance.

When this testing is completed, I will check the size of the 4300 pack, make a decision on pricing and go from there. 

Stay tuned... we are almost there.

Tom


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## Calamityville_Horror (Sep 4, 2006)

I would be interested in trying out two of these.

Great project, by the way. If the cells stand up, they will bring my 9AN back to the front of the line-up.


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## winny (Sep 5, 2006)

I haven't read the entire thread but if there is any sign-up or "post your intrest here", here is mine.

I'm in for one or two packs, given that they will fit the 9AN. If 4300+ mAh is an option at a higher cost, I'm in for that too.

Keep us updated SilverFox!


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## cnjl3 (Sep 14, 2006)

Any news?


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## SilverFox (Sep 14, 2006)

Update:

We are still testing. The pack I sent to Dano fit in his light, but it seems that our nipple length is a bit long. We are adjusting that on the new prototype packs.

The lamp on the 8X, 8AX, and 8NX has two springs that make contact with the top of the battery pack. If the nipple is long, there is a possibility of bending the + spring, and if it goes sideways, it could short things out. There is an insulating washer that goes over the nipple, but our early prototype packs had a thick washer that sometimes would get stuck in the lamp springs. We are in the process of finding a thinner insulating washer.

The longer + nipple also makes putting the pack in the charger difficult. 

The run time and charging tests have been going well. Once I am satisfied with the other "details" we will be good to go.

Tom


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## winny (Sep 19, 2006)

Got my new 9AN yesterday and noticed a couple of things:

1. It's heavy.
2. The battery pack rattles inside.
3. The low output beam sucks.

So, this made me think about the battery packs. As the battery pack is 130 mm long, two 18650 would fit, just. 

SilverFox, 

you mentioned that a fully depleted B90 pack would output over 3.5 V. How come? Don't you discharge both NiCd and NiMH to 1.0 V?
I was thinking about reducing weight and improving the battery capacity to 4.8 Ah using standard LG's.

If Li-Ion is a no-go, I still have questions.

1. What color will your new packs have? Anything but blue would be nice so you can distinguish original packs from the replacement packs easily.
2. What diameter are you aiming at? I understand that your replacement pack must it the 8A*, it wouldn't like it to rattle inside 9ANs either. Is there a good compromise?


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## SilverFox (Sep 19, 2006)

Hello Winny,

You will have to refresh my memory on the 3.5 volt discussion... However, a B90 pack has 3 1.2 volt cells (3.6 volts nominal). If you run the lamp with 2 3.7 volt cells (7.4 volts nominal), you may overdrive things a little.

Shrink wrap (so far) has been yellow.

This replacement pack will minimize the rattle. As a matter of fact, we are trying to reduce the diameter a little to make sure it slides in and you don't have to slightly "press" it in and out. Topper is using a prototype pack in his 9AN and it was a "press" fit at first. Now he has worn the shrink wrap down to where it "slides" in and out. 

Tom


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## winny (Sep 20, 2006)

Here you go:



SilverFox said:


> Hello Sgt,
> 
> It sounds like you have a bad cell in your pack. Are you able to measure the voltage of your pack? Fully charged it should be around 4.3 volts and fully discharged it should be around 3.5 volts or more.
> 
> Tom




Oh, and I did mean to run the Li-Ions in *parallel*, otherwise I wouldn't get 4.6 Ah.


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## SilverFox (Sep 20, 2006)

Hello Winny,

I believe I was referring to resting open circuit voltage after draining the pack down to 1.0 volts per cell under load.

Tom


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## EKinOR (Sep 23, 2006)

Any update on projected availability and price? I've extremely interested in this as I use a 9AN every day at work and my stock of B90's is getting worn out. I also use an L7, too.

If you need another tester, I'd be happy to do it.


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## SilverFox (Sep 23, 2006)

Hello EK,

Welcome to CPF.

We are deciding which cells to use. I can not set a price until we know this.

I am hoping that we will be ready to go in the next few weeks. If I had to venture a guess, I would say that by Halloween the group buy will be in place... as long as we don't experience any set backs.

Tom


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## SilverFox (Oct 11, 2006)

Well, I almost had a set back last night...  

I have several prototype packs and several B90 packs and have been switching between them. I can tell you right now that it is easy to get used to the extended run time of the prototype packs.

Last night I was using my light when it suddenly died. I thought the lamp had died. I had only been using it for... well come to think of it I changed the battery last night and used it quite a lot last night as well. It still didn't seem right.

I tried the light again and it lit up for a couple of seconds, then dimmed right down. Ah ha, dead battery. However I was at a loss why the pack would die off so quickly.

I opened up the light and realized that I had put a stock B90 pack in...  I replaced the battery and was back in business. 

I recharged my prototype packs and am looking forward to extended run time again tonight.

The funny thing is that I had been using my light in a series of short bursts and did not notice any dimming at all. It died when I turned it on for what was supposed to be an extended period of time. I have gotten used to the extended run time of the prototype packs and felt that the run time I got from this pack was a lot less. Well, it was. About half of what I have been used to.

It is hard to go back to a normal B90 pack after "playing" with the prototype packs. Not only is the beam brighter and whiter, but the extended run time is addictive.

OK, I will chalk this up to operator error... It is not really a set back at all.

Tom


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## iced_theater (Oct 12, 2006)

I'll be watching this thread for updates, would be a good battery for my 8nx and would be for an L7 when I buy one.


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## Topper (Oct 17, 2006)

Hi folks, I have not posted on this in awhile well because I have nothing much to say that would be new. I am still getting 60-63 minutes when I leave it on the charger for at least 12 hours after it starts to blink. I am happy with it and after blowing the first lamp I am sure I have far surpassed the "25" hour lamp life on the lamp in my 9AN (if I am keeping up with it we are going on 37 hours use but who's counting? If I was really counting I would know its closer to 38 hours 26 minutes but that sounds to anal). (I hope I did not just Jinx it. I know... its bad luck to be superstitious. am I typing out loud again?) anyway all is good for the proto unit in my care.
Topper


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## SilverFox (Oct 18, 2006)

Hello Topper,

Thanks for the update.

I believe the 9AN has an expected runtime of around 40 minutes on the B90 pack, so 63 minutes is a great improvement. If the larger capacity cells actually work out, I am sure we will be up to 80 minutes for a double runtime pack.

I am just getting the finishing touches done on the 4300 cells and we should be able to get twice the run time from them. Our battery pack builder hurt his back and has not been able to get the 4300 packs to me. I talked with him today and it was his first day back to work. He is going to build the packs tomorrow and I should have them by the end of the week. I will have a week of testing them in the field and will compare my notes from the single cell testing and make the decision as to which cells we will use for these packs.

Once the cells have been picked I can set a price and get the ball rolling for orders. I will start a thread in the Group Buy section when I am ready to go.

I am thinking that the first run will be for about 30 packs. If that sells out, I may have to do another run.

I can see that price will be involved in the final price selection. The GP cells are a premium cell and command a premium price. They will be good for lots of cycles and should hold on to their performance edge for quite some time.

On the other hand, there are some cells that are cheaper...

How do we define "Value?"

I am looking for a bullet proof pack that will out perform the B90 and not give us any problems. My definition of value involves performance first, then price.

Comments...?

Tom


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## cnjl3 (Oct 18, 2006)

Like the old saying goes "you get what you pay for".
So my vote is for performance first!


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## js (Oct 18, 2006)

Hey Tom! How are you? Are you back from the wild lands yet? Or are you uplinked via turtle shell and tincan satellite link?

FWIW, I like your definition of value.


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## SilverFox (Oct 18, 2006)

Hello Jim,

It's nice to be back...  

Tom


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## EKinOR (Oct 19, 2006)

SilverFox said:


> I am looking for a bullet proof pack that will out perform the B90 and not give us any problems. My definition of value involves performance first, then price.
> 
> Comments...?
> 
> Tom



For me, the extra run time would be nice, but not a necessity. Price is important. I use my 9AN 4-5 days a week at work and I'll need multiple batteries, regardless of capacity (unless you can get 4 hours of runtime in a battery pack).

Do you have a rough estimate of price? Full retail on a B90 pack is $20. Is it going to be in the same price range? If they are, I'd be in for at least two and probably more.


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## SilverFox (Oct 19, 2006)

Hello EKinOR,

Welcome to CPF.

The price will be more than the B90 packs. 

The list price on just the GP cells is about $30. This is just for the cells and does not include building them into a pack, testing, forming, and marketing. I am working on a discount from list, but even with a 50% discount I still wouldn't be able to compete with B90 pack price. 

Using the 9AN on the low power lamp you will probably be able to come quite close to 4 hours on one pack.  

Tom


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## SilverFox (Oct 22, 2006)

Update:

I have good news, and more news...

We have solved the fit issue. The change in ribbon and shrink wrap thickness has resulted in a battery pack that fits the lights. A "press fit" to insert the pack is no longer required, and gravity will allow the pack to drop out without having to tap it out. The pack is still larger than the stock B90 pack, so the rattle issue should be minimized.

We have also solved the nipple length issue. Our battery supplier has come up with a nipple that is shorter and works quite well. The old nipple was a little long and would hang up on the charger. The new nipple is short enough to avoid this, but still offers normal operation of the light.

The new nipple resembles the + terminal of a 9 volt battery...  I think someone suggested this earlier. See, we are listening...  

And now for the other news...

The 4300 cells are not working out well. There are reports of them being quite fragile and suffering from high self discharge rates. We had one cell die from spot welding.

I know I was shooting for twice the run time, but I think that we will have to settle for twice the capacity. We are going to go with the GP 3700 cells. They offer better voltage retention than the B90 cells, so we will end up with a brighter light and extended run time. It just won't quite be twice the run time. Oh well, 80+ minutes with an 8NX is a substantial improvement, and the beam is a lot less yellow.

I should tell you that we have had two lamps blow with this improved battery pack. In both cases, the lamps were quite old and probably ready for replacement. I don't think instaflashing will be a problem, but an older lamp may not welcome the improved voltage that this replacement pack offers.

Charging these packs on the old SureFire chargers will probably cause the cells to vent. If you have an old charger and want to try out this new pack, you will do so at your own risk. The new charger goes from red, to green, to blinking green.

I have a bunch of cycles on the new charger and have had no venting issues. I will be forming the packs before they are shipped, and plan to run a few charge/discharge cycles on them to make sure we have a good pack. Keep in mind that I will be going against my general advice of never charging NiMh batteries in a NiCd charger. In this case I think it will work out because the batteries are twice the capacity and the new SureFire charger seems to time out the rapid charge.

I have to place the order for the cells and other parts, and firm up the price with the battery builder before opening up the actual order thread. However, it looks like we will be able to come pretty close to the $38/pack price. This price will NOT include shipping. Those who want 3 or more packs can expect the price to be around $34.50/pack.

Once I have firm pricing, I will open the order thread in the group buy section with a link supplied here.

I am quite excited that this is finally coming together.

Tom


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## Kevski (Oct 22, 2006)

Tom: :goodjob: 

Also, have you had a chance to test these out in an L7? Provided they work in that application I'm in for three.


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## SilverFox (Oct 22, 2006)

Hello Kevski,

Welcome to CPF.

I have not tried them in an L7, but so far the 8NX has the tightest fit and they fit fine in it. This pack will be a direct replacement for the B90 packs.

Tom


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## SilverFox (Oct 24, 2006)

A surprising update:

I went to order the cells today and was told that there is a new 3700 on the block. It seems there are some classes of RC race car racing that limit the batteries to 3700 mAh. GP has just introduced their "special" 3700 cell for this class of racing. It is rumored that these cells may have been labeled for their minimum capacity.

Price was the same, so I ordered them. The race results on these cells has been quite good. I am anxious to check them out. List price on the cells is $7.49 each.

I ordered enough cells to do 30+ packs. When we have all the pieces together and ready to assemble, I will open up the order thread.

I am hoping these new 3700 cells may come closer to giving us twice the run time of the B90 pack. This would allow me to meet the final goal that I set out to achieve.

Keep in mind that if your definition of value only includes price, these packs are not for you. The SureFire B90 packs are around $20, and you can find other packs on eBay that go 2 packs for around $20 + shipping. I picked up a pair of these from "We Know Batteries," and was totally unimpressed. In my 8NX, I was getting about 10 minutes less run time than the SureFire B90 pack. After 22 cycles a cell died in each pack. I tried contacting the seller and they were unresponsive. However, they were cheap... I believe BatterySpace sell some packs for around $16. If you are looking for a cheap pack, I would suggest checking these other sources.

On the other hand, these packs that I will be offering will be of a very high quality. You can expect a long lifetime from them, in addition to the additional run time and brighter beam. These are fresh cells and have been standing up to some real abuse in the RC world.

This is getting very exciting...  

In a few days I will be opening the order thread in the Group Buy section. I prefer that all discussion of the packs be conducted here and the order thread be just for orders. I will be ignoring questions in the order thread (other than order questions), but will be happy to discuss them here. 

I guess it is time to talk about payment options. I think I have most of the bases covered, but will welcome any discussion of how you intend to pay.

Tom


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## sandworm (Oct 25, 2006)

*Re: Twice the Run Time and Brighter… B90 Upgrade*

*Excellent* work on all the R&D. I can attest to the crappiness of those ebay b90 packs. I bought 2 sticks a year or so ago and I've got 1 that charges up to 1100mah and another that goes up to 1400mah. I'll probably wind up disassembling a 7.2V batt pack that uses those GP cells to rebuild these sticks and reuse the hardware, but if I hadn't bought those crap cells I'd definitely jump on this. The overall cost would have been cheaper and I'd be assured to get quality. Either way, kudos on a great job.



SilverFox said:


> A surprising update:
> 
> I went to order the cells today and was told that there is a new 3700 on the block. It seems there are some classes of RC race car racing that limit the batteries to 3700 mAh. GP has just introduced their "special" 3700 cell for this class of racing. It is rumored that these cells may have been labeled for their minimum capacity.
> 
> ...


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## js (Oct 26, 2006)

Tom,

*SWEET!* I love it. That will elimate the only small concern we had with using GP3700's, which was that the cells could potentially be a bit on the old side. And, on top of that, these sound as if they will be incrementally better than the regular GP3700's. Lovely! Delightful!

This is really great. And it's great to see it finally come near to fruition. How long ago was it now that we had that phone conversation where I offered to rebuild a B90 pack or two with Sanyos and/or GP3700's? Over a year ago, wasn't it? Or pretty close, anyway.

It's funny. I don't even own a SF rechargeable, but I just knew we had to do this. And I'm so glad it's turning out this well this soon. And all without ANY hand labor from me! (except for the proto-types, of course) Now that's what I call real fun! Be part of the design and problem solving team, but then let some other schmuck do all the manual labor. Excellent plan.

Anyway, next time we talk, you'll have to tell me all about the RC 3700 cells. I had no idea they existed--(not that I keep close tabs on these sorts of things, though).


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## bobbo (Oct 28, 2006)

SilverFox, 

In Post No.169 you stated you ordered enough batteries to build 30+ battery packs.My question is,are you going to build more packs if the packs sell out in a short time period? I ask this because I want to order at least four of your B90 batteries (I have six SF lights that use the B90 battery) and I'm sure the batteries will sell out fast,so I don't want to be a "Hog". 

Thanks


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## SilverFox (Oct 29, 2006)

Hello Bobbo,

The reason for the low amount of packs is that there is not a lot of demand for the B90 pack. I have two lights that use this pack, and I just did not want to end up with a bunch of packs for it.  Judging from the response I have received, I think this limited run will work out just about right. There should be no problem with your order.

This effort came about because I wanted better performance from my lights. I love my 8NX, but when comparing the beam color to my A2, I see that it is a lot lower in color temperature. The prototype packs have indicated that there is a vast improvement, and I am quite pleased. The beam is whiter and, of course, the run time has been vastly improved.

Tom


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## NotRegulated (Oct 29, 2006)

Tom,
Sounds like they are almost ready! I am post #33 in this thread and would still like to commit to two of these battery packs for my 8NX.


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## SilverFox (Oct 29, 2006)

Hello NotRegulated,

In the next few days we should have all the parts together to get going on this. Once I am certain that we have everything together, I will have the battery pack assembler make some packs. He will then send them to me for forming and a few cycles. Once I am satisfied that everything is good to go, I will open up a thread in the group buy section and you can sign up for the packs you are interested in.

I have checked with our battery supplier and he believes that these special cells will be available at least through the end of the year. If there is a increased interest in these packs beyond this initial offering, we should have cells to build more with.

Stay tuned, we are getting real close to having the final product...  

Tom


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## PGP (Oct 29, 2006)

Glad to see you where able to work things out, and it looks like these will be a very nice upgrade for my 9an. As I stated in post #3, 13, 18 and who knows how many more, I am still interested in 1, but will probably end up getting 2 if they are not to horribly expensive.

Thanks for all the hard work & R&D. :goodjob: 

Patrick


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## dl744tga (Oct 30, 2006)

When you are ready to sell, count this LEO in for at least 1 and maybe two. My 8NX is older, and I have gone thru several B90's that have had poor run times. With the new batteries, can anyone suggest a better bulb for the 8NX? Thanks guys for your hard work, experiments and knowledge. You build it and they WILL come!!


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## SilverFox (Oct 30, 2006)

Hello Dl744tga,

You may find that with the new battery pack you will find the stock lamp "acceptable."  

Tom


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## SilverFox (Oct 31, 2006)

Update:

I was hoping to be ready to open up the order thread today, however we have had a couple of minor set backs. Some of the parts used to build the packs were not the right ones. The new (correct) parts have been ordered and should arrive shortly.

If I was pressed for a new date, I would say perhaps by this weekend...

Tom


----------



## Topper (Oct 31, 2006)

Hi Tom, have you decided upon payment options and price? I prefer CC funded paypal as it seems safe (safe from wife) and easy (lazy man can do that without moving out of chair)  
I owe you for the proto pack and depending on a few things I may want a second pack.
Topper


----------



## iced_theater (Nov 1, 2006)

I'll order some, but I will be gone here for vacation and wont be able to do so until at least the 13th. So hopefully they don't sell out too quickly.


----------



## SilverFox (Nov 1, 2006)

Hello Topper,

I will be able to handle most types of payment including PayPal.

The price will be $38/pack. If you order 3 or more, the price will be $34.50/pack. This does not include shipping.

Tom


----------



## SilverFox (Nov 1, 2006)

Hello Iced theater,

I believe the group buy will still be going on after you get back.

Tom


----------



## Topper (Nov 1, 2006)

Thanks Tom, looks like I owe you 38 bucks for the proto I have (and is still working fine) and I like it enough to want a second one when they are made so I am thinking thats 76 bucks plus the shipping. I am in for 1 (as well as knowing I owe you 38 bucks) 

I will wait to pay when you are ready with the new packs..unless you prefer me to come clean on the 38 bucks:laughing: I can go either way not a problem ( even prepay for a second one)you just let me know and I will get it straight. I really am happy with the proto cell.
Topper


----------



## SilverFox (Nov 4, 2006)

Update:

I am now taking orders in this thread.

Tom


----------



## js (Nov 4, 2006)

Tom,

YOU DA MAN!


----------



## SilverFox (Nov 4, 2006)

Hello Jim,

Perhaps it would be more correct to say "WE DA TEAM!"  

Tom


----------



## js (Nov 4, 2006)

Hey Tom, did I ever tell you that my wife loves your sig line? She was looking over my shoulder one time while I was CPF'ing and saw one of your posts and the sigline and laughed out loud. Guess she maybe thinks there's something to that . . .  Although, now that I think about it, maybe that means she thinks I'm a great man? Err. No. Actually, it doesn't mean that, does it? LOL!


----------



## SilverFox (Nov 4, 2006)

Hello Jim,

 

I have found that it is often a good thing to give credit where it is due...

Tom


----------



## winny (Nov 5, 2006)

How high self discharge did we end up with? As I use my 9AN about two minutes per week, the capacity increase is useless to me if it empties itself in a week like the B90 anyway.


----------



## SilverFox (Nov 5, 2006)

Hello Winny,

Unfortunately, I don't have extensive self discharge numbers for these cells. We have just been having too much fun using them to let them sit around for self discharge tests.

I do have a prototype pack that after roughly 2 weeks ran at about 85% of its initial run time.

You really need to get out and use your light more...  

Tom


----------



## SilverFox (Nov 7, 2006)

Update:

As many of you know, the Pacific Northwest has been having a lot of rain lately. This has resulted in flooding and mud slides. The plastic caps for the ends of the battery packs have been delayed due to the mountain pass being closed. 

This has resulted in a short delay.

I was hoping to have the first packs tomorrow, but will probably not get them until the end of the week.

Sorry for the delay.

Tom


----------



## SilverFox (Nov 12, 2006)

Update:

A week has gone by, and I still don't have any packs...  

The good news is that we came up with a way to reinforce the packs. There was some concern whether they would hold up to being dropped. We have added impact washers between the cells and revised our shrink wrap application to give us added strength.

We also decided to disassemble a cell to make sure the spot welding settings were perfect and not causing any irregularities to the inside surface of the cell. As it turns out, our setting was pretty good, but we just wanted to make sure.

We had 5 packs assembled. I talked to our assembler and he told me that he just wasn't completely happy with them. I told him to stop production so we could get any issues sorted out. We had a chance to go over the whole process again. He took the 5 packs apart and is going to reassemble them using our new procedure. He seems much more happier now.

Once again I must emphasis that we are striving for a quality product. I am sure that everyone is anxious to get their packs, but I want them to be as good as we can get. I don't want returns. This extra work that we did this week should insure a better pack.

Once again, sorry for the delay. I should be getting packs this week.

Tom


----------



## FiftyCalAl (Nov 13, 2006)

tag for later


----------



## SilverFox (Nov 17, 2006)

Update:

The first packs arrived today.

I will be forming and cycling them this weekend.

Stay tuned...

Tom


----------



## SilverFox (Nov 20, 2006)

Update:

Forming and cycling is coming along nicely, but it does take some time to complete. I should be able to get the first order out today.

I have both a 8NX and a 8AX. The lamp in my 8AX seems a little brighter than the one in my 8NX. I have been using the 8AX for run time tests. Aluminum is a better heat sink than Nitrolon.

The reason I mentioned this is because I decided to do some back to back comparisons between the B90 pack and the NiMh B90 replacement pack using the 8AX. 

Here are the results...

Lux at 1 meter indicate about a 7% increase in brightness. 

I am getting about 2650 lux with the NiMh pack and around 2450 with the original B90 pack. Data was taken about 2 minutes into the run time with fresh batteries.

I checked the runtime with batteries "hot off the charger." I pulled the battery pack as soon as the flashing green light came on. They were still warm. The NiMh replacement pack was charged until the green steady light came on, then the battery was removed and reinserted to start the charge again. After the double charge, it was left on until the flashing green light indicated the end of charge.

Run time with stock B90 pack (warm off the charger) and my slightly brighter 8AX was 47 minutes.

Run time with the replacement NiMh pack (double charged and also warm off the charger) using the same 8AX was 95 minutes.

Let's see now 95/47 = 2.0212765. 

Yes, twice the run time...  and brighter...  

It is probably not the best comparison to test the battery packs hot off the charger, but I haven't had time to let one sit around for a day or two. That will be next on the list of things to do.

Overall, I am quite happy with this project. In one test scenario, all my goals were met, and after playing with the prototypes for a couple of months now, it sure is nice to have the additional run time.

Tom


----------



## js (Nov 20, 2006)

Tom,

How do the packs look? What color shrink wrap did we end up with? And I presume that our battery pack maker is now completely happy with the production pack, and that all fit issues and alignment issues are completely solved?

Will you be posting pictures?

Very cool on the "twice the runtime" thing!


----------



## SilverFox (Nov 21, 2006)

Hello Jim,

The packs look good. I will have to take some pictures and post them.

Shrink wrap is white, and the fit is very good. It is tighter than a "drop in" fit in the charger, but it fits the lights perfectly.

The first order was shipped out today.

Tom


----------



## SilverFox (Nov 21, 2006)

The problem with running a single test and drawing conclusions from it is that you could be off a little...  

I just did another run time test with my stock B90 pack and got 49 minutes. Since the absolute best run time I have been able to get on the NiMh replacement pack is 97 minutes, I am ending up just short of twice the run time...

Bummer.

Tom


----------



## SilverFox (Nov 30, 2006)

Update:

I just picked up an L7. It is a very nice addition to the 8AX.

SureFire lists 1 hour of regulated light followed by 1.5 hours of dimming, but useful, light using the B90 battery. I stuck one of these NiMh B90 replacement packs in and turned it on. 

An hour went by and the light was still in regulation. Two hours later, the light is still in regulation. Finally, at 2.5 hours the light starts flickering indicating that it was dropping out of regulation. 

Impressive, that is a vast improvement in run time.  

I pulled the battery pack and measured the voltage. It was at 2.8 volts, which is around 0.93 volts per cell and indicates that the pack should be recharged.

Hmmm, perhaps this is not as spectacular as I first thought...

I then grabbed a B90 pack and did the same thing. I got about 1 hour until the light dropped out of regulation. I left it on for an additional 1.5 hours. At the end of that time, I could look the 5 Watt LED straight on without discomfort. Yes, in a dark room there was still "useful" light, but it may be stretching it a little.

I pulled the B90 battery pack out and it was at 3.1 volts. A little over 1.0 volts per cell...

Now just a minute, how can this be?

I decided to do another test with the NiMh B90 replacement pack. This time I ran it until it went out of regulation, slightly over 2.5 hours, then left it on for an additional 1.5 hours. Now I am at 4 hours total run time, and it was still brighter than the original B90 pack was at 2.5 hours. 

I pulled the battery pack and it had recovered to 3.2 volts. Slightly higher than the standard B90 pack.

I decided to do another test. This time I was going to go until the light was as dim as it was with the stock B90 pack.

5 hours later, I can look at the beam straight on and it is time to stop the test. I pulled the battery pack and it is at the same 3.1 volts the stock pack was at.

I am impressed. I have gone from 1 hour of regulated light to 2.5 hours of regulated light. Also, I have gone from 1.5 hours of dimming (but "useful" ) light, to 2.5 hours of dimming (but "useful" ) light. The total possible run time of 2.5 hours with the original pack has been increased to 5 hours with the NiMh replacement pack. YES!!!

My general recommendation is to recharge after the light falls out of regulation, but if you need some additional light after it falls out of regulation, this pack will deliver that as well.

Tom


----------



## js (Nov 30, 2006)

Holy RUNTIME, Batman!!!

Nice improvement there, Tom!


----------



## gdhumphreys (Nov 30, 2006)

Hi Tom.

I have a SF L7, so the extended runtime is very good news for me. Looking forward to getting my replacement B90 battery.

Greg


----------



## monkeyboy (Nov 30, 2006)

2.5 times the bright-output-runtime! That's incredible. I cant wait to try them out.


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## W4DIZ (Nov 30, 2006)

Tom,
Thats Great news!
I have both the 8nx and the L7 that I use at work everyday.
Now we just have to wait for the postman to get you the MO for the 4 packs I ordered.
I hate waiting.
Thanks for all of your hard work.


----------



## bones_708 (Dec 1, 2006)

I saw a replacement pack for the B90 that claims twice the run time. I hate to even bring it up and am not trying .............. well, to be a problem. It's made with 4200 cells and claims 3300mAh. How would these compare?

http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2527


----------



## js (Dec 1, 2006)

bones_708,

That pack is not made with 4200's even though the little SC cell link takes you to a 4200 cell. It is made with 3300's; 4200's wouldn't fit. Our pack is made with 3700's, and really GOOD 3700's at that.

Other than that I can't say much, as I have never experienced the batteryspace upgrade B90 pack. Perhaps Tom will buy one and report. Or perhaps someone who already owns one could send it to Tom for testing. Or buy one of our B90 upgrade packs and compare them for themselves and post about it.


----------



## monkeyboy (Dec 1, 2006)

The picture shown on batteryspace doesn't have neg washer contact at the top of the pack. It won't work on the L7 and 8?? series if that is the case.


----------



## bones_708 (Dec 1, 2006)

Js, Thanks for the info. I thought that there would be something like that. I just hated to see all the work you guy's put into this be rendered unnecessary. If no one else has this pack I might see if Tom would like to test it if I sent one. I'm still waiting my turn so I don't have anything to test it against.
Mind you I would still trust Tom's conclusions more than my own right now anyway. 
If these are any good they may make decent extras tho I planned on buying 2 from Tom for my lights.


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## monkeyboy (Dec 1, 2006)

I'm trying the new batteries for the first time today. Thanks for emailing instructions Tom. The batteries feel very solid and well built. Here's a picture against the old B90s.







I like the white shrink wrap and those end caps


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## SilverFox (Dec 1, 2006)

Hello Bones,

I just ordered one of the battery packs listed on BatterySpace. I will do some testing on it and we will see how it does.

Tom


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## SilverFox (Dec 1, 2006)

Hello Monkeyboy,

Our "official" end caps got delayed, so I improvised. Those should be a "custom" fit...  

I haven't had time to post a picture, so thank you for yours.

Tom


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## SilverFox (Dec 9, 2006)

Update:

I received the B90 replacement battery from BatterySpace. It does not work. It is just like the picture shows, there is no negative contact at the top. 

I called them and they wanted me to send them my B90 pack to see what the contact was like, or at least send them a picture of what it looks like. Hmmm, this does not build a lot of confidence in them.

They are supposed to get back to me...

Tom


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## iced_theater (Dec 11, 2006)

For these B90 packs, you say to charge until the light goes green, then take the battery out and put back in and wait until it goes flashing green right? Would it charge up to max capacity if you just leave the battery in the charger overnight *say 12 hours*?


----------



## SilverFox (Dec 14, 2006)

Hello Iced theater,

I have tried charging overnight and it does not seem to get the pack fully charged. You get roughly 70-75%, but not a full charge. You could probably get a full charge by leaving it on for a week, but it is quicker just to do a second charge cycle.

You still will get more run time than the original B90 pack with a single charge cycle, but it will be below the full capability of the pack.

I put a mark on the pack. During the first charge cycle, I insert the battery so the mark is not showing. When I go for the second charge cycle, I rotate the pack so the mark is showing. This way, I can look and see if the pack is fully charged.

If you need to use the pack after the first charge cycle, that is fine. You will only get around 60-70 minutes of run time with an 8AX, but there is no problem using it that way.

Tom


----------



## SilverFox (Dec 26, 2006)

Update:

It seems that our supply of the GP 3700SP batteries has dried up. I guess this project is winding down.

I have heard some good initial reports, but we will have to get some cycles on these cells to see how well they do. I have been checking out a variety of other cells, but none of the others will hold voltage as well as these cells do. I can get longer run time, but the light starts to dim down about half way through the run. These GP packs have spoiled me...  

I just did a run time check on a pack made with the IB 4200 cells. I got 115 minutes. The only problem is that the pack does not fit in the SureFire charger. It is too long.

I think there are only a couple of people left that haven't received their packs, so I think we are just about done.

Thank all of you for your support during this project. We should have some performance reports trickle in, and IF I find another supply of the SP cells, I may make some more.

Tom


----------



## Lodogg2221 (Dec 26, 2006)

Man, somehow I missed out on this. Gotta check back more often and not rely on email updates I guess.....
If you make more, let me know!


----------



## SilverFox (Dec 26, 2006)

Hello Lodogg,

I think I still have a few packs left. There are a couple of people that have not responded yet. I will have to see if they are still interested. I also have some packs that tested lower than I wanted them to. I am planning on taking them apart to find the questionable cell, then rebuild them with matched cells.

How many packs were you interested in?

Tom


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## Lodogg2221 (Dec 26, 2006)

I think maybe just one, ($38 right?) but do they work in the standard charger? I have a very new style, and another that is about 2 years old, but both have red, steady green, and flashing green for indicator. If Id have caught this sooner Id have gotten at least two...


----------



## SilverFox (Dec 26, 2006)

Hello Lodogg,

They seem to work just fine in the newer style charger. The newer style is the one that goes from red, to green, to flashing green. The only difficulty is that you have to do 2 charge cycles to get these high capacity pack fully charged.

Let me see where we end up and I will get back to you. I will put you on the tentative list.

Tom


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## Luminator (Dec 26, 2006)

SilverFox said:


> There are a couple of people that have not responded yet. I will have to see if they are still interested.



I'm still in for 3 packs. Is the price still 34.50 for 3?


----------



## Lodogg2221 (Dec 26, 2006)

Alright, thanks.


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## RazorMaxx (Dec 29, 2006)

Oh crap, I have been wanting some of these for a long time but just now found this thread. I had to stay away for a while due to poor spending habits (for lack of better words ). I too have not liked the b90's but really like my SF rechargeables. I have always wondered why this has not been addressed by SF? 

Anyway, I am in great need of up to 4 of these packs however I would be greatful if I can just get one! If you have any left and can help me out please let me know. It may even be easier to just email me direct at inspired44atearthlinkdotnet. My paypal is near zero nut I can send a USPS money order out anytime!

Thanks so much!

Dave


----------



## SilverFox (Jan 28, 2007)

Update:

Someone was asking about self discharge rates...

I just finished a test with a pack that was fully charged, then stored at room temperature for a month. It ran for 80 minutes.

Tom


----------



## Lodogg2221 (Jan 28, 2007)

So were/are there any extra packs available? 

Im getting awfully tired of my factory packs. I just charged one yesterday, ran it today for 5 min and it dimmed down, then ran for another 15-20 and died.


----------



## SilverFox (Jan 28, 2007)

Hello Lodogg,

I have 2 left...

Tom


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## Lodogg2221 (Jan 28, 2007)

How much for both? Can you email me the total and payment info?


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## SilverFox (Apr 23, 2007)

Update:

If you remember, in December 2006 I ordered the advertised B90 NiMh replacement battery pack from BatterySpace to test out. When I received the pack, it did not have the negative contact required for use in the 8AX, 8NX, and L7 lights. They told me that they would look into this and see what they could do.

I have been in contact with them (monthly) and finally have an answer from them.

Their pack is not suitable for these lights. 

They don't have the necessary hardware to get this pack to work, and can not seem to be able to find a source for it. 

They have refunded my money.

Tom


----------



## HKocher (Jun 12, 2007)

Any updates on this project? Thanks.


----------



## SilverFox (Jun 12, 2007)

Hello HKocher,

I have found a new source for cells. Their specification sheets show performance similar to the GP cells. I have some in route from China and will make up some packs with them and check them out.

No promises... but still working on it.

Tom


----------



## LuxLuthor (Jun 15, 2007)

SilverFox said:


> Update:
> 
> If you remember, in December 2006 I ordered the advertised B90 NiMh replacement battery pack from BatterySpace to test out. When I received the pack, it did not have the negative contact required for use in the 8AX, 8NX, and L7 lights. They told me that they would look into this and see what they could do.
> 
> ...



I had fun reading this thread, even though I don't have any lights that need them. I especially love that the battery is still listed at that link (even if not in stock)

It caught my interest because wptski said something about battery pack contact welds were a cause of failure with these. Sounds like it was the heavier welding required to attach that special nipple.

I was also told that the 3 mil nickel strips work fine in battery packs putting out 30A, and the 5 mil in packs putting out 50A. Beyond that end to end soldering reduces the resistance better.


----------



## SilverFox (Jun 15, 2007)

Hello LuxLuthor,

If I remember correctly, the cells we were using were thinner on the sides than on the nipple and negative end. When the negative contact strips were welded to the sides of the bottom cell, it sometimes punched through the can.

I am not sure if other cells have similar construction.

We ended up using the 3 mil strips, and used 4 welds at each connection.

Tom


----------



## LuxLuthor (Jun 15, 2007)

Tom, that can also happen if you have the power and/or pulse width turned up too high on the welder for a given nickel strip mil thickness and/or battery end plate thickness.


----------



## depusm12 (Aug 15, 2007)

SilverFox any more news on the new cells for these packs?


----------



## SilverFox (Aug 15, 2007)

Hello Depusm,

I am just starting to test some cells that a contact sent me from China. The manufacturer seems to be reputable, but we will have to see how the cells test out.

I have just started forming them.

Tom


----------



## depusm12 (Aug 24, 2007)

SilverFox said:


> Hello Depusm,
> 
> I am just starting to test some cells that a contact sent me from China. The manufacturer seems to be reputable, but we will have to see how the cells test out.
> I have just started forming them.
> ...


 
SilverFox

Have you made any batteries yet?
Any more news?


----------



## SilverFox (Aug 24, 2007)

Hello Depusm,

I am at cycle 25 on the new cells. They are doing very well, but are not the performers the GP 3700SP cells were. On the plus side, they were a lot cheaper.

The still beat the original B90 cells by quite a bit, but I don't think we will be getting close to my goal of twice the runtime.

Testing is still in progress.

Tom


----------



## FiftyCalAl (Sep 5, 2007)

well, if anybody can produce us a great product, I'm certain Tom will do it. I have his original cells. He worked long and hard on those and they are top notch - well worth the elevated price (compared to SF cells). I'm just waiting till he can find comparable (or better cells) to make some more. :thumbsup: Alan


----------



## SilverFox (Sep 6, 2007)

Hello Alan,

I am glad you are enjoying your replacement pack. Those packs are the cream of the crop and have set a very high standard to follow.

I have come up with some other cells. They are quite a bit cheaper, but don't have the performance of the GP 3700 SP cells. The still are better than the original B90 packs. We have brighter, but not twice the run time.

My battery pack builder and I have been giving the Tenergy cells a lot of testing. They seem to be pretty good holding voltage under load, but fall a little short on run time. They are also a little smaller, so all of the issues we had with things barely fitting will become non issues with these cells.

I may have to work up some pricing on packs using these cells. I don't think I can beat SureFire's price, but may be able to come in a little over.

I have been testing cells that come in at around 3000 mAh. There are also some that are supposed to come in at around 3300 mAh. I am planning to get some of those cells for testing to see how well they hold voltage under load.

I am thinking that if I could get the price down to $30 or less, people would be happy even if they didn't get twice the run time.

Tom


----------



## depusm12 (Sep 6, 2007)

I would be interested in at least 2 of the new packs.


----------



## HKocher (Nov 13, 2007)

I'm in for 2-3 if these become available again. My B90s leave much to be desired.


----------



## SilverFox (Nov 14, 2007)

Hello HKocher,

I think I will put together some packs with the Tenergy cells. I may call upon you and James to do some field testing for me...  

Tom


----------



## depusm12 (Nov 14, 2007)

SilverFox said:


> Hello HKocher,
> 
> I think I will put together some packs with the Tenergy cells. I may call upon you and James to do some field testing for me...
> 
> Tom


 
Let me know Tom, I would be happy to help, plus it would give my 9N new life.


----------



## HKocher (Nov 16, 2007)

SilverFox said:


> Hello HKocher,
> 
> I think I will put together some packs with the Tenergy cells. I may call upon you and James to do some field testing for me...
> 
> Tom



Sounds good to me, I don't mind being a guinea pig.


----------



## Lodogg2221 (Nov 19, 2007)

Even if they arent as good, Id probably take 2. I love the ones I got from the first run! 
I dont like the B90s, they dont hold a charge for long, and they dont last very long, especially compared to the replacements...


----------



## RAF_Groundcrew (Nov 23, 2007)

Tom, 

Am I missing something? Is the issue with the old packs (of which I have 1) the availability of the GP 700 cells? 

I did a quick ebay search and found a few sources for GP 3700 cells, both assembled into raceing model packs, and loose.

Forgive me if I've ovelooked something, this is a long thread, and I seem to remember when you declared you would no longer be producing the improved packs, I was saddened, as I'd just got one, used as part of an L7 package deal from a member.


----------



## SilverFox (Nov 24, 2007)

Hello Nigel,

The improved NiMh B90 pack increases the run time of the L7, but it is best used with your 8NX. Used in the 8NX, you will see quite a difference over the stock pack.

The cells I used were a special run of GP 3700SP. The plane 3700 cells did not give the performance I was looking for.

The other issue is cost. The premium SP cells were very expensive. I am looking at trying some 3300 cells that are quite a bit cheaper. The performance is not up to the 3700SP cells, but it is still better than the stock B90 pack. 

The H-MPV cells look interesting, but I have not tried them out.

Tom


----------



## depusm12 (Jan 2, 2008)

Tom 

Any new news on these new packs?


----------



## SilverFox (Jan 2, 2008)

Hello James,

I am back to trying to find some good cells. I got some Tenergy cells and had consistency "issues."

Tom


----------



## depusm12 (Feb 27, 2008)

Any more news on these B90 upgades Tom?


----------



## nfetterly (Nov 5, 2008)

Looks like I came upon this thread 2.5 years late, but then again I didn't have a 9AN 2.5 years ago, I just wanted one.

Any status update / availability? I couldn't pm you (not enough posts? too much lurking soaking up information...).

Neale


----------



## SilverFox (Nov 5, 2008)

Hello Neale,

Welcome to CPF.

The original cells used for this project are no longer available. I have been searching for cells that are at least as good, or better, and have not been able to come up with suitable replacements.

I have been running some tests on Saft cells. They are not as good as the original cells, but they seem to do a decent job. I may have to make up some packs with those cells...

As far as I know, all the research and testing efforts I put into this project have panned out very well. I had one pack returned because it started to vent at a spot weld site, but other than that they seem to be still working very well.

Now if GP would do another run of the 3700-SP cells, we would be back in business...

Tom


----------



## divine (Nov 5, 2008)

Is 6 for 80 a good price? :duh2:


----------



## Mr Happy (Nov 5, 2008)

divine said:


> Is 6 for 80 a good price? :duh2:


Who knows? (They don't actually seem to be available for purchase so the price listed is rather academic  )


----------



## divine (Nov 5, 2008)

js knows. 

That's true, not many other prices out there. :candle:


----------



## DocD (Nov 5, 2008)

hi these are on ebay UK http://cgi.ebay.co.uk/GP-4300mAh-H-Mpv-1-CELL-1-2V-4300-mAh-Sub-C-BRCA-legal_W0QQitemZ370103605248
it say 4300mAh could these be any good for the battery pack?
DocD


----------



## js (Nov 6, 2008)

Even if you could get them, you wouldn't want them at this point, I don't think (unless they were cells from a new production run). Old NiMH cells are a bad deal, unless they have been given regular maintenance charges!


----------



## DocD (Nov 6, 2008)

i think there the very lastest desigin but here maybe some more http://cgi.ebay.co.uk/ANSMANN-RACIN...-race-Cells-1-2V-4500_W0QQitemZ220306373172QQ
use the Dcell type in my P7 mag seem very good to me


----------



## SilverFox (Nov 6, 2008)

Hello Divine,

Those are the GP 3700 cells. The ones I am interested in are the GP 3700-SP cells. 

As Jim mentioned, if there are any left they are probably not in good shape unless they have been well cared for.

Tom


----------



## SilverFox (Nov 6, 2008)

Hello DocD,

The higher capacity cells tend to develop high rates of self discharge. They work well for RC racing because they are used hot off the charger, but in our application the high rate of self discharge works against us.

Tom


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## divine (Nov 6, 2008)

Okay.


----------



## Crazyeyes (Aug 14, 2009)

Any updates?


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## LittleJoseph (Dec 11, 2009)

The only thing new about me is as a member of this forum, however, I am constantly looking for better batteries to replace the B90. I have read most of the thread with great interest and do not necessarily understand the language being utilized. I did noticed a thread in the general flashlight area and took a look at the following link posted there. http://www.batteryspace.com/index.as...OD&ProdID=2527
Has anyone seen this battery or know anything about it??
Have a GREAT Day!
"The difference between a successful person & others is not a lack of strength, not a lack of knowledge, but rather a lack of will."
Vince Lombardi


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## Crazyeyes (Apr 15, 2010)

Your link doesn't work.


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## SilverFox (Apr 15, 2010)

Hello Crazyeyes,

Welcome to CPF.

The battery linked to was not compatible with the B90. Batteryspace removed its listing after several people purchased them and returned them.

Tom


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## NotRegulated (Apr 15, 2010)

Silverfox,
I'm still using the two packs I got from you last time! They hold a charge for a fairly long time and still give great runtime. My B90's don't last nearly as long. You did a good job on the construction as well.

thank you!


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## SilverFox (Apr 16, 2010)

Hello NotRegulated,

Those cells were a matter of being in the right place at the right time. I haven't been able to find a similar quality cell since then, and I have been looking.

My packs are also doing great too.

I am glad you are getting lots of use from them.

Tom


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## NotRegulated (Apr 16, 2010)

If you find some cells that meet your standards, I'll be in for more.

My 8NX with good cells is a joy to use. There is something about the simplicity of the 8NX, the feel of Nitrolon and the beam of a hotwire; especially if it's rechargeable!


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## Chrontius (Jun 8, 2010)

*sigh*

One of these days, I'll buy four of your awesome new batteries (two 8X, one 8NX, and one day I'll own a 9N) and a few spares.

What about a single large li-ion cell with appropriate fittings?


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## NotRegulated (Nov 5, 2011)

Time to resurrect an old thread now that Surefire has discontinued it's rechargeables and B90 replacement packs are impossible to find.


Silverfox, 
Any thoughts about the possibility of doing another project for B90 batteries now that no one sells them? If not, any recommendations as to where custom packs can be made to order? I still love my 8NX and the batteries I got from you a year and a half ago still work very well.


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## Lodogg2221 (Nov 5, 2011)

Agreed.
I have one in my 8AX and 9AN, and both are still going strong! 
But I dont like the idea of once they are gone, my lights are out of commission...


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## NotRegulated (Nov 7, 2011)

At this point I would say forget "twice the runtime"; I'd just go for a chance to buy new battery packs at the regular runtime!


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## SilverFox (Nov 8, 2011)

Well, I have kind of lost tract of the sub C cells that would work the best. The GP cells I used are still working great.

Let me poke around a little and see what I can come up with.

Tom


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## Stephen Wallace (Nov 8, 2011)

www.cheapbatterypacks.com have a couple of their Elite branded SubC cells, but they don't list max. discharge rate in the description.


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## NotRegulated (Nov 20, 2011)

This site was just posted on another CPF thread where another member is also looking for replacement B90 batteries. It appears that someone on Ebay is selling new after market Surefire B90 NiCd Rechargeable Battery Pack's. 
http://www.surefireb90batteries.com/

I still would go with a recommendation from SilverFox.


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## fivemega (Nov 21, 2011)

*$30 for just the battery? Better get complete 8AX for $80*

http://www.lapolicegear.com/surefire-8ax-commander.html


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## NotRegulated (Nov 22, 2011)

Not a "complete" 8AX...
$80 for the flashlight plus one rechargeable battery (8AX000). The "complete" 8AX is $110 which includes the flashlight, two batteries, and the Charger (8AX415). 

Still a great deal for a great light but the uncertainty of getting any battery packs in the future for this system makes the purchase less than satisfying.


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## Lightingguy321 (Jan 9, 2012)

anyone try one of those aftermarket b90 batteries from that ebay seller yet? I am hesitant on buying anything NiCd these days, I would much rather go with a NiMh replacement


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## Undpilotalex (Mar 6, 2012)

Read this thread from start to finish... Around page 2 I was thinking I'm gonna order some of these, then I looked at the date. 

I am interested in a few of these if you ever do start production up again.


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## js (Mar 9, 2012)

Sanyo still makes both a NiCd and a NiMH subC cell. The "HR-SC" and "HR-SCU" are the NiMH and the "NC-2500SCR" is the NiCd--it may be the minor evolution of the 2400 mAh cell I used in the proto-type pack I made. Anyway, personally, I just don't trust the RC community cells anymore, as they are made for extreme performance over just a handful of discharges, so it doesn't matter if the separator is so thin that the self-discharge rate is really, really bad. And it doesn't matter if they don't have the cycle life, because they get thrown out after a couple dozen races. So their priorities are different than flashlight battery pack batteries. But, perhaps others have extensive experience with, say, the Elite SC cells, and can vouch for them. Problem is--and I speak from PAINFUL experience--you can test out a cell and love it and watch it last and stand up and be high quality, then place an order for 200 cells, and find that THOSE ones are all crap. With Sanyo, on the other hand, by and large, you can expect consistency and quality. In my book, it's worth giving up the bleeding edge performance and capacity in order to guarantee quality.

Cost for the Sanyo SC cells is on order of $5-$8. Rebuilding a B90 pack with the SANYO cells is trivial, as you can re-use the SureFire B90 pack hardware. The Gold Peak cells, on the other hand, were too much larger in diameter to fit the old hardware so we had to come up with custom hardware. Which we DID do. Those were some awesome B90 packs Tom sold!

Anyway, point is that with the Sanyo cells, someone like me can take an old, dead B90 and rebuild it. So that's a thought as well.


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## NotRegulated (Apr 6, 2012)

I have found that a Streamlight Stinger battery works inside of my 8NX, however, it is about a 1/4" inch short so I used a spacer (four nickels wrapped in masking tape) for the time being. I drop the spacer down into the tube first, then place the battery in. This setup works fine to power the 8NX. You either need a Streamlight Stinger/Streamlight piggyback charger to charge the battery OR you can buy one of the empire stinger battery chargers for around $22. Team it with the best NIMH battery and you have a battery solution for your Surefire 8NX for around $40.


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## dano (Apr 6, 2012)

Streamlight now offers NIMH Stinger battery sticks. To use them as a "B90" goto Radio Shack, buy some 9volt battery connectors. Remove the smaller tab from the connector, and solder to the center (+ node) of the Stinger stick. You will then have a B90.

-dan


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## monkeyboy (Apr 6, 2012)

Ah yes, I remember this thread. This is probably the first thing I ever purchased here on CPF. I bought 2 of them; One has gone bad due to lack of use but amazingly one is still as good as new and is still giving the rated capacity on a discharge test with a model charger! The packs are almost 6 years old, and at one point went a whole year without charging at all which is normally a sure way of killing a NiMH battery. If these had been li-ion, the overall capacity would be way down by now.

I wonder if it will still be retaining its capacity in another 6 years? 

I'm using it with a Surefire L7 which I have recently upgraded with a Cree XM-L U2 bin, although admittedly it doesn't get much use these days.


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## enchantor (Oct 24, 2012)

Just got a 9an Commander from a friend. No charger and unknown how good a shape the battery is in. Did some googling and came to this thread.

Is the battery offered in this thread still for sale? and a charger to go along with it? Thanks anyone for your help. If I'm in the wrong place, please point me in the right direction. Thank you!


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## dano (Oct 24, 2012)

enchantor said:


> Just got a 9an Commander from a friend. No charger and unknown how good a shape the battery is in. Did some googling and came to this thread.
> 
> Is the battery offered in this thread still for sale? and a charger to go along with it? Thanks anyone for your help. If I'm in the wrong place, please point me in the right direction. Thank you!



Look at my post in this thread about adding a nipple to a Streamlight Stinger battery. For a good charger, i like this one: http://www.batteryjunction.com/fbc-ncd-1.html

Surefire had a lot of problems with the last generation B90 batterys and charger, and it would be tough to find an original one that works correctly.


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## andygold (Nov 22, 2013)

dano said:


> Look at my post in this thread about adding a nipple to a Streamlight Stinger battery. For a good charger, i like this one: http://www.batteryjunction.com/fbc-ncd-1.html
> 
> Surefire had a lot of problems with the last generation B90 batterys and charger, and it would be tough to find an original one that works correctly.



dano....just to make sure i understand you. If I pick up a Stinger NiMH battery and solder on the + terminal from a 9 volt battery, will it fit right, and charge properly and fully in the Battery Junction charger? If the charger is made for a stock Stinger battery, won't the addition of the 9 volt top make it too long?

Is there any trade off in doing it this way compared to using an actual B90 replacement?

Will the Stinger NiMH with 9 volt terminal soldered on fit in the OEM Surefire B90 charger? i have both the old charger, and the newer "blinking-green-light" chargers for the B90. Will the newer Surefire charger fully charge a NiMH, or will it only work for NiCd?


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## wiestom89 (Oct 26, 2016)

Hello Silverfox,

is it still possible to purchase replacement Batteries from you?

Best regards Tom


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## SilverFox (Oct 27, 2016)

Hello Tom,

Welcome to CPF.

Sorry but no. This project ended some time ago and I have not pursued it further.

Tom


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