# Got the new D-cell Lithium Ion



## LEDite (Sep 27, 2007)

Received D-cell #32600 from Kai yesterday.

Positive post barely extends above the body.

Charged it up tonight and did a little testing:

Charged to 4.2 Volts

Discharged @ 1.5 amps (about 1/3 C)

Internal resistance measured @ 80 milliohms.

This value is a little high for a 5 amp cell.

Some of my new Sanyo #18650 cells have less internal resistance.

More testing to do.

Where are my 1 D cell lights now ???

Larry Cobb


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## cfromc (Sep 28, 2007)

I've had these in my cart on Kaidomain for several days while I've waited for someone to report any information on them. I've also been trying to wait for someone to sell some protected D cells. I think I may just pull the trigger on these. For $15.50 each, it may be hard to go wrong.


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## quantile (Sep 29, 2007)

Received mine a few days ago. Here is a discharge graph to 3V at 1.5A, that's about the maximum discharge current on my charger without using an external resistor to dissipate heat.







The current tapering off is part of the charger's discharge program, I put a marker at the point where the cell could not hold 1.5A without dropping below 3V.

Marcus


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## paulr (Sep 29, 2007)

These have almost 4x the volume of an 18650 but only 2x the capacity? Hmm.


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## DM51 (Sep 29, 2007)

Hmm indeed. I don't think I will be getting any of these.


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## barkingmad (Sep 30, 2007)

paulr said:


> These have almost 4x the volume of an 18650 but only 2x the capacity? Hmm.



18650 cells often state capacties around 1800-2200mah but rarely are - certainly not at a 5A draw (see below) and not that I would really recommend it as it is more than 2C for a 18650.

Those D cells are actually about 2.8x the volume (not 4x) of a 18650 if my maths serves me correctly and probably also about 2.8x the capacity.

So far I have tested 4 of these D cells at a 5a (1C) draw - the capacities have been between 4200mah and 4400mah which seems pretty good. I am currently discharging them again at 2.5a (0.5C).

Once the 2.5a test is done I will test a few 18650's at 2.5A to compare capacities.


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## Bushman5 (Sep 30, 2007)

where do you get these graphs from?


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## barkingmad (Sep 30, 2007)

Bushman5 said:


> where do you get these graphs from?



Well I do my tests using a CBA-II and by the look of it the graph below was from a Orbit Pocketlader / Microlader running the Microlog software?

The CBA-II is purely a discharger but it can do constant rate (A) discharge and up to about 100w if I remember correctly (5A from one of these D cells is about 15-20w).


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## barkingmad (Sep 30, 2007)

barkingmad said:


> 18650 cells often state capacties around 1800-2200mah but rarely are - certainly not at a 5A draw (see below) and not that I would really recommend it as it is more than 2C for a 18650.
> 
> Those D cells are actually about 2.8x the volume (not 4x) of a 18650 if my maths serves me correctly and probably also about 2.8x the capacity.
> 
> ...



First 2.5A test complete - the 'D' cell that previously tested at 4300mah at a 5A draw - now gave 4600mah at 2.5A draw. Second cell running now...


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## Bushman5 (Sep 30, 2007)

barkingmad said:


> Well I do my tests using a CBA-II and by the look of it the graph below was from a Orbit Pocketlader / Microlader running the Microlog software?
> 
> The CBA-II is purely a discharger but it can do constant rate (A) discharge and up to about 100w if I remember correctly (5A from one of these D cells is about 15-20w).



sorry, noob to electonics, i take it this is a desktop battery tester with computer interface? 

can you recomend a beginners basic battery tester? (i'm new to charging LI-ions, have some RCR123's on the way and dont want to them to explode like they are apparently prone to do).


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## barkingmad (Sep 30, 2007)

Bushman5 said:


> sorry, noob to electonics, i take it this is a desktop battery tester with computer interface?
> 
> can you recomend a beginners basic battery tester? (i'm new to charging LI-ions, have some RCR123's on the way and dont want to them to explode like they are apparently prone to do).



The risk seems far more likely when being charged - so really you need a good Li-ion charger - typically one that cuts off at 4.20v (or slightly below) and 'cuts off' (some people have reported some chargers not cutting off) when the charging is complete.

It depends on your budget but I most often use an Orbit Pocketlader but it's relatively expensive.


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## quantile (Sep 30, 2007)

barkingmad said:


> So far I have tested 4 of these D cells at a 5a (1C) draw - the capacities have been between 4200mah and 4400mah which seems pretty good. I am currently discharging them again at 2.5a (0.5C).



Interesting, so these cells don't loose much capacity at 1C discharge. I think I will be getting a few more of these...



barkingmad said:


> Well I do my tests using a CBA-II and by the look of it the graph below was from a Orbit Pocketlader / Microlader running the Microlog software?



Yes, it's a Pocketlader. Much cheaper than a Schulze and it can do almost the same. Got mine a two years ago, no regrets so far. I highly recommend it to anyone looking for a more 'serious' charger. Needs a 12V power supply though.

Marcus


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## JimmyM (Sep 30, 2007)

I just got the 4 that I ordered. I charged them in pairs in a balance charging rig I put together using my Bantam BC-8. I haven't made measurments on mine yet. I seems to me that if the cell delivers 5000 mAh at 0.2C then it is a true 5000 mAh cell. Looks pretty good since it delivers 4600 @ 2.5A (0.5C).
In my opinion, it's not just a comparison of cell volumetric efficiency.
I can now get 5000mAh in a single cell without boring for a pair of 18650s and still have to deal with additional length. I just drop them in.
I put together a Mag275 (temporarily using the hotdriver from another light) last night using a copper 2D Mag. Great light. Bright, great 2D size.
I'll be trying them in a 4D driving a 62138 when I get a chance. I'll be building a new charging rig for up to 6 cells with balancing.


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## barkingmad (Sep 30, 2007)

quantile said:


> Interesting, so these cells don't loose much capacity at 1C discharge. I think I will be getting a few more of these...
> 
> 
> 
> ...



Running the 0.2C discharge at the moment - will post the results soon (if I forget someone PM me!).

Recommend the Orbit Pocketlader as well - great charger - not cheap but good quality and lots of features. A 12v supply is easy enough to find these days - you can get 12v 5a power supplies for about $20-25 or use a 12v lead acid battery.


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## MattK (Sep 30, 2007)

paulr said:


> These have almost 4x the volume of an 18650 but only 2x the capacity? Hmm.




Remember that high volume production cells (cells with large markets) lead to more competition among mfs which leads to greater energy densities. 18650's are by far the largest volume li-ion cell whihc means there's been the greatest competition among mfrs which means considerably higher energy densities. It's like AA NiMh vs 9V NiMh. 9V NiMh cells could probably be 350mah by now but there's not enough of a market demand to generate the R&D and production machinery changes necessary for their production so their increase has increased relatively slowly. AA's, on the other hand, have massively increased in capacity over the last 5 years from ~1600 to ~2500mah


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## barkingmad (Oct 1, 2007)

At a contstant 1a (0.2c) load the first two have tested ~4600mah - second two cells testing now.


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## JimmyM (Oct 1, 2007)

So even going down to 0.2C from 0.5C didn't really increase their delivered capacity. I'd say these are 4600mAh cells instead of 5000mAh. But I'm still happy. My Mag275 is happy.


barkingmad said:


> At a contstant 1a (0.2c) load the first two have tested ~4600mah - second two cells testing now.


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## Supernam (Oct 2, 2007)

Are these protected cells? I'm thinking of shoving 3 of these in a Magcharger with an 1185 bulb. Modify the charger with a 3cell LiIon charger. What do you guys think?


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## barkingmad (Oct 2, 2007)

JimmyM said:


> So even going down to 0.2C from 0.5C didn't really increase their delivered capacity. I'd say these are 4600mAh cells instead of 5000mAh. But I'm still happy. My Mag275 is happy.



Compared to how many manufacturers rate their cells the fact that we are seeing 4500mah+ is pretty good.

I did a test on two 18650 cells - they were rated at 2200mah but at a 2a draw only gave around 1450-1500mah - so these 'D' (32600) cells are about 2.7x the physical size but also 3x the capacity.


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## JimmyM (Oct 2, 2007)

Supernam said:


> Are these protected cells? I'm thinking of shoving 3 of these in a Magcharger with an 1185 bulb. Modify the charger with a 3cell LiIon charger. What do you guys think?


Sorry. They're not protected.
Since they're not protected, I'd suggest charging individually, or use a balance charger. On the other hand, it might just work fine and you'd be in business. 3 cells isn't really all that much.
Cool idea. Be careful of instaflash with the 1185 on 3 Li-Ion though. These cells aren't gonna sag quite as much as 3 2200 mAh 18650s.


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## den_s (Oct 3, 2007)

quantile said:


> The current tapering off is part of the charger's discharge program, I put a marker at the point where the cell could not hold 1.5A without dropping below 3V.



I have a pocketlader too that I highly recommend. You can disable that 'deep discharge' by setting AUTO-DSCHRG to 'No - I/1'. Although it is a cool feature, I don't particularly like to discharge my batteries that far.

Cheers,
Dennis


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## cnjl3 (Oct 3, 2007)

I'm tempted to order a couple of these cells to tide me over until the
7500mah D size li-ions become available.



JimmyM said:


> I'd say these are 4600mAh cells instead of 5000mAh.


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## plasmaman (Oct 3, 2007)

I got one of Kai's D cells to test and ran a CBA test on it at 4 amps. Here's a graph comparing the 5A D cell with the 7.5A D cell (see this thread)https://www.candlepowerforums.com/threads/168809








At $15 the 5A cell is good value. The 7.5A (if it becomes available) will be a lot more, but then they are two different animals in terms of build quality and performance. The higher energy cell is much closer to its stated capacity.

Has anyone tried the 5A C cell from DX yet - I just ordered them. Looks like they have a nice +ve contact cap.


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## JimmyM (Oct 3, 2007)

This is EXACTLY what I was hoping to see. A direct side-by-side comparison of the 2. Cool. No REAL surprises here, but it's great to have a quantitative comparison.
If Ultimate performance is needed, the 7500mAh cell is the way to go. For "normal" performance, the Kaidomain cell is the better value.
It will be really expensive, but the 7500 cells are the way to go for a 64623/64458 bulb in a 4-6 cell light.


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## barkingmad (Oct 4, 2007)

plasmaman said:


> I got one of Kai's D cells to test and ran a CBA test on it at 4 amps. Here's a graph comparing the 5A D cell with the 7.5A D cell (see this thread)https://www.candlepowerforums.com/threads/168809
> 
> 
> 
> ...



The KD 'D' cell is actually close to the stated capacity - typically around 4500mah - or at least far nearer than many I have tested.

The DX 'C' cells have tested nowhere near 5000mah - think just over half that - will recheck my CBA graphs.

But the other cell plasmaman certains seems better - hope they do not end up too costly!


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## flash-x (Jun 1, 2008)

Hi. Has anyone tested these D cells?
http://www.kaidomain.com/WEBUI/ProductDetail.aspx?TranID=4141


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## Chrontius (Jun 3, 2008)

Yes. They'll do incredible things with ROP-lo, but won't light ROP-high and the protection circuit kicks on until they're placed back on the charger.

A little disappointing since I bought them for the ROP-hi, but the runtime is incredible.


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## flash-x (Jun 3, 2008)

Thank and capacity 5000mAh matches?


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## 2xTrinity (Jun 4, 2008)

Chrontius said:


> Yes. They'll do incredible things with ROP-lo, but won't light ROP-high and the protection circuit kicks on until they're placed back on the charger.
> 
> A little disappointing since I bought them for the ROP-hi, but the runtime is incredible.


With a soft starter, such as an NTC resistor or preferably a PWM soft starter, liek the AW hotdriver, the LiIon D-Cells will light up anything up to the Philips 5671, which draws 5.5A continuously, almost double the ROP low. I've gotten fantastic performance out of two Kai D-Cells in that build.

Short circuit protection kicks in at 6A. The thing is, that the lower voltage bulbs without a soft starter lamp draw an inrush current "Spike" that is enough to trip this short circuit protection.

Also, since the cells themselves are so good (the latest batch, NOT the ~2007 batch discussed in the initial posts in this thread), and it's only the crappy circuit that causes the short circuit protection to kick in so early, I plan to buy four of these sometime in the future, strip the proteciton circuits off them, re-wrap them into a shrink-wrapped pack of four with my own protection circuit on it, then use it to drive a ~100W superbulb. I should be able to get almost triple the runtime of heavier 4D lights using NiMH Cells.


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## Norm (Jun 4, 2008)

.


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## 270winchester (Jun 6, 2008)

flash-x said:


> Hi. Has anyone tested these D cells?
> http://www.kaidomain.com/WEBUI/ProductDetail.aspx?TranID=4141



i would like to, but I still haven;t gotten my battery after I ordered it on Apr 18th. Buyer be ware.

I'm not holding my breath. Does anyone else sell D Li-Ions?


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## iq2k (Aug 9, 2008)

270winchester said:


> i would like to, but I still haven;t gotten my battery after I ordered it on Apr 18th. Buyer be ware.
> 
> I'm not holding my breath. Does anyone else sell D Li-Ions?


 

I think AW is now selling D LI-Ions.
Try them you'll find them on the forum.
However i'm almost sure you'll get your stuff from slow old Kai eventually.
I think they nead to get into the i'm in for type aproach to pre-ordering bulk for resale.


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## DM51 (Aug 9, 2008)

iq2k said:


> I think AW is now selling D LI-Ions.
> Try them *you'll find them on the forum*.


Where?


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## TigerhawkT3 (Aug 9, 2008)

iq2k said:


> I think AW is now selling D LI-Ions.
> Try them you'll find them on the forum.
> However i'm almost sure you'll get your stuff from slow old Kai eventually.
> I think they nead to get into the i'm in for type aproach to pre-ordering bulk for resale.


I think you mean C Li-Ions.


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## sLightlyObsessed (Aug 18, 2008)

I just posted pictures of a cheap and easy fix for the protected D-cell li-ion KD battery pack so that they will light up high current lamps. I posted it here, in another thread, but I think it's appropriate here as well. Check out my build!


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## Anders (Aug 19, 2008)

Hello.

I asked him a month ago:


07-20-2008
Originally Posted by *Anders* 
_Hello AW.

So, how is it going with the D cell Li-Ion cells? (protected)

Do you have any of this type soon to offer?

Best Regards/Anders_



------------------------------------------------------------------------

"-I am working on D cell with safe chemistry.

Regards,
AW"
------------------------------------------------------------------------


Today I received my two D Li-Ion from Kaidomain, I'll hope I soon get the light to use them with 


Anders


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## PhantomPhoton (Aug 19, 2008)

I know that LiFePO4s do exist from Chinese manufacturers in D size. I haven't bothered buying one yet as I don't have that much money to toss around at the moment and no LiFePO4 charger. Plus they're only 3000mAh. But on the bright side they can do 60A supposedly.


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## Anders (Aug 19, 2008)

Hello.

I also did a discharge with one of my cells.








My values is better than previous tests.

Pretty good with 5A load.

Description: 1 Li-ion cell, 5.0 Ah @ 5.00A
Started At: 08/19/08 20:48:23 Västeuropa, normaltid
Discharge Rate: 5.00 A
Starting Voltage: 3.83 V
Ending Voltage: 3.00 V
Total Time (hh:mm:ss): 0:55:33
Tested Capacity: 4.63 Ah

Anders


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## mitch79 (Aug 19, 2008)

Thanks for the discharge graph Anders.
These cells do look better than the earlier batch.
I'd like to know how much there capacity improves at 1.5A discharge.


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## Anders (Aug 22, 2008)

Hello mitch79.

As requested:








Now it is better and far better than previous tests.
A real 5Ah cell:twothumbs

Anders


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## mitch79 (Aug 22, 2008)

Thanks for your efforts Anders :thumbsup:.
4.9Ah @1.5A is a great improvement on the previous cells .

I requested the 1.5A discharge graph as I have ordered a 2x32600 8.4V pack from KD to be used in a 2D Mag P7 I'm building. 

Thanks again


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## jirik_cz (Aug 27, 2008)

Hello Anders. Those test are with protected or unprotected D li-ion? Thanks.


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## Anders (Aug 27, 2008)

Hello jirik_cz.

Kaidomain Store Order#***** Protected single D Li-ion (32650/32600)

EDIT: *SKU: S004141

* Anders


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## monkeyboy (Aug 27, 2008)

Volume comparison between D and 18650:

Pi x 1.6^2 x 6 ~ 48.3cm^3

Pi x 0.9^2 x 6.5 ~ 16.5cm^3

So D size is about 2.9x the volume of 18650, which still gives 18650 the advantage in volumetric energy density (but we already knew that).

What we should actually care about is the volumetric energy density of the host with batteries installed. In the case of the [email protected] D host, D size li-ion is much better than a dual bored 18650 configuration.


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## Synergic (Oct 9, 2008)

Hi there!

Can i use 3 of these protected d liion cells in parallel and charge them? Reference in KD?

Are Kaidomain unprotected ones as good as the protected ones?



Thanks.


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## Iliger (Dec 21, 2008)

Anders said:


> Kaidomain Store Order#***** Protected single D Li-ion (32650/32600)
> EDIT: *SKU: S004141*


Hello Anders,
What are their exact dimensions? Judging by the definition they must be 32 mm. in diameter, 65 mm. in length. But completely different sizes have shown at the site . Do they normally fit in Mag 4D (with shorty tail spring maybe?)
Will they work at 10 amp. perfectly?
Price is for one battery?
Thanks.​


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## Anders (Dec 21, 2008)

Hello Iliger.

32,60x65,83mm.

Price was for one cell.

I don't own any Mag:s.

The only test I did with them was the ones in previous answers so I dont know about 10A.

Its hard to find them in Kaidomains site, when searching on the SKU:+ number it wont work but when searching on (32650/32600) it works.*

* 
Anders


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