# Panasonic AAA Ni-MH question



## guiri (Jan 2, 2010)

Guys, I just bought some Panasonic cordless phones and they came with panasonic brand Ni-MH AAA's rated at 630mAh.

Now, the screens are very big and bright and I don't get the same talk time out of them as my older phones with smaller and not so bright screens.

I assume that going to a more powerful battery would improve things but my questions are:

If I go from 630 to 1000mAh, will I get almost double the talk time or not?

How are these numbers usually? Over or underrated or what?

What's the most powerful AAA and is it worth the money or should I go for a lesser battery at lower cost. Ie, compare these two..
http://www.batteryjunction.com/onepcsofaaa1.html 89 cents each
http://www.batteryjunction.com/ges-nh1000-bp.html 3 bucks each

Finally, how about my Eneloops which seem to be 800mAh?

Thanks

George


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## 45/70 (Jan 2, 2010)

AAA NiMH's are my second most used cells. That is to say I have far less experience with AAA's than AA's. That said, I've used a number of different brands, some good like Sanyo 900 and 1000mAh, and some lesser brand/generic types.

From the experience that I have had, I'd be willing to bet that the eneloop AAA's will out perfrom any of the "standard" NiMH cells after the first year of use (very possibly sooner). From what I've seen here on CPF and elsewhere, they'd probably out perform the other LSD NiMH cells as well.

While LSD cells are not necessarily best for use in something like a cordless phone that gets charged and discharged frequently, that's still what I'd go with if I was in your situation.

Hey, now that Panasonic has bought out Sanyo's battery division, you'd stll be using OEM cells,.....well sorta! 

Dave


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## guiri (Jan 2, 2010)

So, eneloops then?

What's LSD? (Not the drug, right)


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## 45/70 (Jan 2, 2010)

guiri said:


> What's LSD? (Not the drug, right)



Ha! No, LSD=*L*ow *S*elf *D*ischarge.

Yeah, I'd use the eneloop AAA's.

Dave


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## guiri (Jan 2, 2010)

Thanks


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## GarageBoy (Jan 2, 2010)

45/70 said:


> While LSD cells are not necessarily best for use in something like a cordless phone that gets charged and discharged frequently, that's still what I'd go with if I was in your situation.
> 
> Dave


Use it til it dies and then charge?


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## 45/70 (Jan 3, 2010)

Most cordless phones cut out at about 1.2 Volt/cell so, yes, that'd be OK. Of course NiMH cells can be charged most anytime you want, provided you do run them down every couple months or so.

Dave


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## guiri (Jan 3, 2010)

Alright, I don't really understand. Eneloops are Ni-mH or what? Run them dry every time?

The phones not in use, should I keep them on the chargers all the time?
Let the batteries die and only charge when I need them, or
Keep rotating them all so that they all get SOME use?


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## Anders (Jan 3, 2010)

Hello guiri.

"To prevent potential irreparable harm to a battery due to polarity reversal of one or more cells during
discharge, the load (discharge current) must be terminated prior to the battery being completely discharged.

Continuing the discharge to lower end
voltages can slightly increase the delivered capacity, yet if the end voltage is set below the
recommended Voltage Cutoff the cycle life of the battery will be decreased."

It is not a good advise to drain NiMh completely, ever.
If you dont know at what voltage the phone cutoff you cant use it til it dies.

Anders


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## 45/70 (Jan 3, 2010)

guiri, Anders is correct about it being bad for a NiMH cell to be discharged to zero Volt. Under load, a NiMH cell typically shouldn't be discharged to a voltage lower than ~0.8-0.9 Volt, or discharged to a level where after resting a bit, the open circuit voltage (OC) of the cell reads less than ~1.20 Volt.

It is my experience with cordless phones however, that they usually start warning of a low battery condition at some point above 1.2 Volt/cell OC, and stop working completely at around 1.2 Volt/cell OC. I have a Panasonic KX-TGA2438 handset here for example, that the display goes blank and all functions quit once the pack (2x5/4 AAA) voltage reaches 2.4 Volts OC. This translates to 1.2 Volt per cell (2.4/2=1.2) and is quite an acceptable discharged voltage for NiMH cells.

I don't usually let the phone discharge until it quits, as I need to know that it will work, and need to use it. I do however try to let it discharge until it quits, once every month or two. This prevents any memory effect, helps balance the chemical distribution within the cells, and prolongs the overall life of the pack.

Your phones may be different. I'd hazard a guess that they work similarly though. It wouldn't hurt to check the voltage of the cells to see at just what voltage they do quit working. If the cells are at ~1.20 Volts when the phones quit, you're good to go. 

Dave


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## vali (Jan 3, 2010)

Keep in mind that the actual capactiy of an eneloop is less than regular NiMH but I think 45/70 suggested them not because their mAh, but for their toughness and slighty higher voltage.


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## 45/70 (Jan 3, 2010)

In reference to vali's post above, yes, and as I alluded to in post #2, after a year (or less) the eneloops probably will have a higher capacity than 900 or 1000mAh standard AAA cells.

And to clear a couple points up,



guiri said:


> The phones not in use, should I keep them on the chargers all the time?



No, I wouldn't do that. eneloops, and all NiMH cells for that matter, don't like to be trickle charged constantly. It's better to just have the handset on the charging cradle when you are actually charging the phone. Once charged, leave it off until you want/need to charge it.

I think a lot of cordless phone manufacturers make a lot of extra $ by stating that you can "leave the phone on the charging cradle when not in use". They sell a lot more replacement battery packs using this recommendation. I learned about this the hard way. My phones that I left on the charging cradle when not in use had an average battery pack life of about one year (oddly enough, that's what the phone manuals also speculated). After learning that constant trickle charging NiMH cells was not good for them, I started not leaving the phones on the charging cradle when not in use, except for charging. My battery packs now last 3-5 years. 



> Keep rotating them all so that they all get SOME use?


That's not a bad idea, since you are using individual cells, rather than battery packs.

Dave


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## guiri (Jan 3, 2010)

45/70 (as in the caliber?)

I'm sure my panasonics are just like yours and I DO charge them when they start warning (at least these new ones, the older ones got to the point that they just died on me) and yes, for the same reason. I need one working not one that just dies on me.

What about the other phones (I got 6 handsets), should they be on the chargers all the time or should I alternate and use them or what?

Oops, I see you answered this. HEre's the thing, if I don't charge them and keep them on the chargers, should I simply take the batteries out, charge them and put them away then? Otherwise the phones will completely discharge them if they're inside the phones, right?

THanks again guys


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## 45/70 (Jan 3, 2010)

guiri, cells or packs that I'm not using, I try to store not fully charged or fully discharged. It doesn't always work out that way, but fully charged is probably better than fully discharged, as it insures the voltage doesn't drop too low.

Yes "45/70" is in reference to the rifle caliber. I am a gun collector, and my specialty is straight stocked lever action repeating rifles (but including single shot Winchester High Wall and Sharps falling block levers, as well) of the old American West.

The 45/70 is probably my favorite caliber of these arms, in part because it has been in use for over 135 years, and can still hold it's own reasonably well today, particularly with smokeless powder handloads. Any shop that carries a reasonable selection of rifle ammunition will likely have 45/70 in stock, although, as I said, I pretty much handload exclusively. My favorite rifles in this group are the Winchester models 1886 and 1885, Marlin Model 1895, and the Model 1874 Sharps.

I use "45/70" rather than "45-70" because originally, it meant a ._*45*_ caliber bullet over (*/*) _*70*_ grains of FFg or FFFg black powder. When the 30-03 Springfield (._*30*_ caliber introduced in 19*03*) came out, and later the 30-06 and other "modern" cartridges, a lot of the old designations changed over to the newer format, although not actually correct for the older black powder cartridges.

OK totally OT! 

Dave


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## Niconical (Jan 3, 2010)

I use 2xAAA eneloops in a cordless phone. 

For charging, I remove the batteries, replace with fresh eneloops, and charge the used cells myself (Maha C9000). 
I never actually put the phone on the charger/base station. 

That way the batts are charged properly, and the phone is always ready to go.


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## guiri (Jan 3, 2010)

Niconical, the problem is I'm too damn lazy to do that AND, I think when you take out the batteries, you then have to register the handset with the base unit every time..

Dave, so you are saying I should discharge batteries PARTIALLY before storing? Why?

Hey, got any pics of your guns?

I just traded a printer for an AK myself 

Gearing up for the SHTF scenario. That or the zombie invasion 

I've even looked at this cool .50BMG that's only 14 lbs total IF I ever get the money.


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## Eugene (Jan 3, 2010)

I just bought a set of these Panasonic cordless phones, the chargers are smart chargers, they will shut off when the batteries are charged. You should see the charge light turn off and the display will say charged when its complete. So there won't be any worry about the usual over charging due to truckle chargers.
I have a MAHA c9000 charger and number all my batteries and will run them through a refresh every 6 months to a year depending on if they are heavily or lightly used (batteries 1-8 stay with the digicam for example and are heavily used while 9-16 may be for the scanner which is lightly used to every year) and record the capacity so I can determine if they are still performing good. I can do the same with the phone batteries now too.


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## guiri (Jan 3, 2010)

Holy crap that's ambitious. 

Thanks Eugene


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## Eugene (Jan 3, 2010)

you will find that quite normal in this forum. People with a lot of batteries will number or otherwise ID them in some way to keep track of them, after you get a couple dozen batteries you have to keep track of them in some way. Then couple with the higher end chargers like the c9000 haveing the refresh and break in cycles letting you test the capacity you can be sure the batteries in your digicam are still going to work.


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## Robin24k (Jan 3, 2010)

I would imagine that LSD cells would actually not be prefered in this situation? Given that the cordless is used on a regular or frequent basis, capacity should be more important...


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## 45/70 (Jan 4, 2010)

guiri said:


> Dave, so you are saying I should discharge batteries PARTIALLY before storing? Why?



I don't like to store NiMh cells with a full charge, as self discharge occurs faster, and to a larger extent when cells are near full charge. Self discharge is probably the biggest cause of large crystal formation (a major cause of voltage depression) in nickel based cells. So, if you're not going to use them for a while, it doesn't make sense to store them fully charged, IMO.



Robin24k said:


> I would imagine that LSD cells would actually not be prefered in this situation? Given that the cordless is used on a regular or frequent basis, capacity should be more important...



That is what I was suggesting in post #2. The LSD ability isn't really put to good use in a device that is charged/discharged frequently. However, as I mentioned in later posts, it's likely that AAA eneloops would actually have a higher capacity than high capacity "standard" NiMH cells within a year, or even less. So, why not use them in this application? Makes sense to me. 

Personally, I've pretty much abandoned high cap cells. Their voltage doesn't hold up as well under load, and their capacity drops in time, compared to eneloops.

Dave


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## ltiu (Jan 4, 2010)

I got the same Panasonic NiMH 630mAh in a pair of cordless I got last year. I replaced with 1000 mAh Duracells. I've had no issues with talk times.


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## Robin24k (Jan 4, 2010)

45/70 said:


> it's likely that AAA eneloops would actually have a higher capacity than high capacity "standard" NiMH cells within a year, or even less. So, why not use them in this application? Makes sense to me.


Ah, I see. I'm not as informed about the AAA market as my Panasonic cordless uses AA-based battery backs.


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## guiri (Jan 4, 2010)

Eugene said:


> you will find that quite normal in this forum. People with a lot of batteries will number or otherwise ID them in some way to keep track of them, after you get a couple dozen batteries you have to keep track of them in some way. Then couple with the higher end chargers like the c9000 haveing the refresh and break in cycles letting you test the capacity you can be sure the batteries in your digicam are still going to work.



Not me brother. You have no idea how lazy I am and I have OVER 100 AA eneloops 

Sad isn't it :mecry:


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## guiri (Jan 4, 2010)

45/70 said:


> I don't like to store NiMh cells with a full charge, as self discharge occurs faster, and to a larger extent when cells are near full charge. Self discharge is probably the biggest cause of large crystal formation (a major cause of voltage depression) in nickel based cells. So, if you're not going to use them for a while, it doesn't make sense to store them fully charged, IMO.
> 
> 
> Personally, I've pretty much abandoned high cap cells. Their voltage doesn't hold up as well under load, and their capacity drops in time, compared to eneloops.
> ...



Well, I have an assload of eneloops so that's an easy choice for me. Actually, I have an assload of AA's, I need more AAA's

So, what? Discharge the rest of my stored cells just a little bit?


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## guiri (Jan 4, 2010)

ltiu said:


> I got the same Panasonic NiMH 630mAh in a pair of cordless I got last year. I replaced with 1000 mAh Duracells. I've had no issues with talk times.



What kind of difference in talk times do you see? Rough improvement in % if you can?

10%, 50%, 100%?

Link to where I can get the duracells?

Thanks


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## guiri (Jan 4, 2010)

Robin24k said:


> Ah, I see. I'm not as informed about the AAA market as my Panasonic cordless uses AA-based battery backs.



Robin, the older ones do which forces you to buy packs. I like the new option better as I can just buy regular AAA's and still use them for other stuff.


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## Robin24k (Jan 4, 2010)

I got my grandparents a set with AAA's, and they've managed to kill the OEM set of batteries in one handset in about a year. I got him a pack of Duracell NiMHs, but that was before I stumbled on CPF, so I don't know if they're Duraloops or not. They seem to be holding up pretty well...so far...


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## guiri (Jan 4, 2010)

Robin, you mean the original aaa's from panasonic?


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## Robin24k (Jan 4, 2010)

Yeah, the original OEM Panasonic batteries.


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## guiri (Jan 4, 2010)

Thanks


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## ltiu (Jan 4, 2010)

guiri said:


> What kind of difference in talk times do you see? Rough improvement in % if you can?
> 
> 10%, 50%, 100%?
> 
> ...



Can't measure unfortunately. It's with my mom and she talks and talks and talks. So far no complaints from her.

The duracells I got were not LSD cells. These are regular non-LSD green Duracells like these:


http://base0.googlehosted.com/base_...d=500&op_sharpen=1&size=20&dhm=7946cbe8&hl=en


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## guiri (Jan 4, 2010)

Well, I may have to get some. I DO have a $35 reward zone coupon from best buy.

So, should I get LSD or NON LSD cells for my phones? I'm asking again 'cause frankly, I DO have a hard time understanding this. Sorry guys.

Also, does it say on the packs what kind they are? LSD or not?


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## quattros (Jan 4, 2010)

Hi Guiri,

It happens I have a set of the oem panasonic cordless phone aaa nimhs doing a discharge/refresh in my bc-900 charger right now. I've been using this set in my phones for over a year and they show a capacity of about 700mah.

In my opinion you'll be fine running the oem panasonics until they die.

I've been using them in my 3 panasonic handsets for over a year and they still work great. They're not bad for oem. I get about 2-2.5 hour runtimes with speakerphone enabled.

I plan on upgrading to batteries when I start noticing a drop in runtime, but I feel that the frequency of phone use makes eneloops overkill.

I store the handsets on the chargers because they shut off once the charge is complete.


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## guiri (Jan 4, 2010)

Well, I love my new phones with two exceptions. I hate where the headphone jack is located (totally retarded) and the fact that they don't last as long but, that's what you get for having a big, bright and beautiful display. No complaints really but IF I can improve this by simply getting new batteries, why not. Can't have enough batteries anyway.

Yeah, we get spoiled and that's what happened with my old panasonics. They lasted forever on good battery packs and I would like the same here.

These are the ones I have and yes, the display IS that bright..
http://images.smithgear.com/KX-TG7434B-BIG.jpg


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## Robin24k (Jan 4, 2010)

guiri said:


> So, should I get LSD or NON LSD cells for my phones? I'm asking again 'cause frankly, I DO have a hard time understanding this. Sorry guys.
> 
> Also, does it say on the packs what kind they are? LSD or not?


The short answer is that you want capacity. LSD or not won't really matter if you use the handset frequently.

As for LSD cells, look for Eneloops or Duracell Pre-Charged with white tops. Some of the Duracells have black tops and are Made in China. Those are the same price, but the white top Made in Japans are better.


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## guiri (Jan 4, 2010)

THanks and thanks to the others as I have a feeling this was answered earlier. Again, I'm a bit of a dumbass!


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## Eugene (Jan 5, 2010)

The extra capacity of a high capacity cell won't be of any use unless your using the phone for very long talk times. If you make a shorter call then drop it back on the charger or just carry it around with you then LSD will fit. I find that LSD works best most any time unless your doing hot off the charger run time tests, very few real world situations the high capacity do better.


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## guiri (Jan 5, 2010)

Well, sometimes I DO talk for a very long time...say, 30% of the time.


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## shark_za (Jan 6, 2010)

All good advice but also consider this. 

I have seen that "industrial grade" quality NiMh cells rated at say 650mAh actually give that at a 500mAh discharge. 

I thought I would be clever by switching from these cells to Uniross Hybrio (800mAh-LSD) or Energiser 850mAh till I tested them all next to each other. 

They all gave around 650mAh at any decent discharge rate. 

I don't have any AAA cells rated at 1000mAh but if they are the same technology as 2700mAh AA cells I would expect the 800mAh LSD's to beat them.


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## guiri (Jan 6, 2010)

Yeah, the problem is that I'm still kinda lost but don't feel bad guys and don't feel you've wasted your time. I'm sure others are reading this too. In any case, I'm going to try eneloops for awhile and see what that gives me


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## 45/70 (Jan 6, 2010)

As I mentioned earlier, after 50 charge/discharge cycles (eg. once a week in a cordless phone, for a year.), I seriously doubt that the 900-1000mAh "standard" high cap NiMH cells will be able to match an 800mAh eneloop in capacity. The "high cap" NiMH's just don't hold up well in this regard. 

Dave


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## guiri (Jan 6, 2010)

Alright, so as dumb as I am, from what I can gather from ALL the posts  is that I should just stick with my eneloops then?


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## 45/70 (Jan 6, 2010)

You're not dumb guiri! If nothing else, look at all you've learned from just this thread! :hairpull:

As, for using the eneloop AAA's, as I said, I would, but that's just my opinion. 

Dave


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## guiri (Jan 6, 2010)

See? You're assuming I learned something 

Well, I kinda did 'cause we've settled on the eneloops


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## Bright+ (Jan 26, 2010)

I'm not sure what method Panasonics use to detect battery status. I picked up a Philips CD 445 which uses a pair of 750mAh AAAs and it requires to be charged in the handset to reset the indicator. 

When I installed a pair of fully charged AAAs from an external charger, the phone was perpetually stuck on low battery warning which can't be ignored, because it beeps every minute during a call.


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## SilverFox (Jan 26, 2010)

Hello Bright+,

Welcome to CPF.

I also have noticed that Panasonic doesn't recognize a fully charged battery pack unless it has been charged in the handset. On my unit, there is no beep, but the charge status indicator shows low battery. 

One thing I never got around to checking was to put the handset in the charger for a short period of time. This may give the indicator a partial charge that may cause a change in its displayed status. I would think that about 15 minutes would do for a test.

Tom


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## PeAK (Jan 26, 2010)

SilverFox said:


> Hello Bright+,
> 
> Welcome to CPF.
> 
> ...


Tom,
Given what we've guessed about the new NiMH AA powered cordless phones, it seems that the unit is a timed charge that is trigger when the battery is detected to be low. I think this also happens when new batteries are inserted and it just assumes that they are in need of charge. Hence the low indication with freshly charged external batteries.

As the NiMH batteries seem to have good reliability, it would also make sense that there is no trickle charge as is often found in NiCad based cordless phones....maybe it's something we should try to emulate with our collection of NiMH batteries used to power our adult toys.


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## Mr Happy (Jan 26, 2010)

Newer Panasonic phones may have improved their intelligence in this regard. We recently bought a new Panasonic phone for my mother, and to speed things up I charged up some of the batteries in an external charger before putting them in the phone. With the pre-charged batteries the handset showed "two bars out of three" on the charge indicator, and with the factory fresh batteries another handset showed "one bar" (the batteries arrived in the package with some charge).


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## Bright+ (Jan 26, 2010)

NiMH AAAs have a higher internal resistance than NiCd 2/3AA or AAs that are common and Philips CD 445 draws a significant amount of current for AAA when it is in speaker phone mode which drops the voltage. The temporary voltage sag causes the indicator to go down a notch and latch in place. On many cell phones, the indicator may go down under load, but comes back up with voltage recovery.

Not so on Philips design though. 

I'm not so sure of charging technique, but it's not a constant flow. It's pulsed at 100mA and 0mA. I'm not sure if it continues indefinitely like that or if it employs a means of termination/switching to trickle.


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## dannstrait (Jan 26, 2010)

I've had a Panasonic KX-TG9361B for about a year and half now. I posted my initial comments about the phone in this thread as referenced by Peak in post #48.

I have a few thoughts I think will be helpful. The runtime of my phone has gotten considerably shorter even though I rarely keep the phone in the charging cradle except to periodically charge. Suspecting my cells were at their end, I performed a break-in cycle on my C9000 and found that one cell had around 500mah of capacity remaining, while the other cell had just over 400mah. Not bad after 20 months of use (about an hour a day).

My real reason for posting is in regards to the so-called "smarts" of this phone. This in an older model so Panasonic may have improved the circuitry by now (as per Mr. Happy's post), but I think this phone works on a simple timed charge and may or may not go into trickle afterward as Peak and Silverfox have suggested.

Recently, I started to charge the batteries on my C9000. I take them out of the phone, charge them and put them back into the phone. Regardless of the batteries' SOC, the phone will demand a 7hr charge simply because the cells were just inserted. After reinserting the batteries, I placed the phone back into the cradle with fully charged batteries...with frightening results. Expecting the phone to detect full batteries and stop charging, I came back hours later to find it still charging and the batteries were burning hot! The charge rate used by the phone is much too low to provide peak detection; it's doubtful if the phone has a maximum voltage cutoff either.

Ever since then, I've been determined to only charge the batteries on the cradle if the phone goes dead on me. This way, I know the cells are empty and won't be horribly overcharged. When I charge the cells on the C9000 and reinsert them, I drop the phone in the cradle for a couple seconds and then immediately remove it. This clears the "Charge For 7 Hrs" message. After this trick, the phone displays only 1 of 3 bars of battery life but retains its full amount of talk and standby time. If I leave the phone in the cradle longer, it won't stop charging until 7 hrs have passed.

I have an identical handset that is brand new with fresh batteries that exhibits the same behavior. As a result, I believe the battery life indicator has more to do with charge time than cell voltage. When I fully discharge the cells and let the cradle charge the batteries for 7 hrs, the battery life indicator does indeed display a full 3 bars but the talk and standby times remain the same as when I use the C9000 trick.

In regards to guiri's question about having to re-register the handset - that's not the case with my phones. They stay registered even when I remove the batteries.

My sister has the newer Panasonic phones (thanks to my recommendation :naughty that use the same AAA 630mah batteries. Next time I visit, I'm going to do the remove/reinsert trick to find out whether the circuitry has gotten smarter.


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## Mr Happy (Jan 26, 2010)

I'd have to suggest that on the whole, home cordless phones exhibit dinosaur technology out of the stone age. If you compare them to typical cell phones, they are completely out of date: they don't have smart entry for names in the address book, they don't have USB or any kind of synchronization interface and they have really primitive displays and menu systems. Considering that the initial development costs must have been amortized many times over by now, it is really surprising that they don't have better technology inside them.


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## Magic Matt (Jan 26, 2010)

We have Panasonic DECT cordless phones - model number isn't on them though sorry. They are sleek looking black units which have full colour screens, smart entry phone books, synchronisation of phone books between handsets, ability to 'conference call' between handsets and the land line, support caller line ID and SMS. No way near as good as the mobile phones I agree, but then I can't see any point putting a camera and MP3 player in a land line phone...

They do charge at a higher rate and then drop down to virtually nothing. I have tested this by putting a "watt watcher" on the power supply - when the phone is almost depleted it's pulling 1.6 watts, and that drops to just under 0.4 watts. I don't know what else the electronics in the dumb charger stations do - I think there may be an amp etc. in there as they all have a button to make the handsets ring if you lose them, plus an illuminated blue bit around the edge.


One thing I've never understood... the main complaint with these type of phones is you can't use them if you have a power cut because the base station requires power from the mains, meaning in a power cut a cheap standard phone works and the fancy one doesn't. Why isn't there a backup battery in the base station so you can still phone out in an emergency?


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## Mr Happy (Jan 26, 2010)

Magic Matt said:


> We have Panasonic DECT cordless phones - model number isn't on them though sorry. They are sleek looking black units which have full colour screens...


Sounds like the KX-TG842x series, which are the ones in my post above. Did you note they are not really smart though? When you enter names in the address book they don't automatically capitalize the first letter of a name and lower case the rest, you have to do that manually. And they don't, for instance, have voice recognition of names for dialing. So they seem slick, but they are still very behind the times.


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## guiri (Jan 26, 2010)

PeAK said:


> ....maybe it's something we should try to emulate with our collection of NiMH batteries used to power our adult toys.



Peak, kindly keep your wife's toys out of this discussion... :devil:


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## guiri (Jan 26, 2010)

Well, I thought mine remained registered, at least the older units but these new ones, I'm not sure. In any case, I could have screwed up and just tried to use a handset that wasn't. I did after all get SIX handsets when I bought these refurbished on ebay.

As for the model number not being there, it probably is but it's molded into the phone and I think it's usually on the bottom of the phone on the small part where it touches the table or whatever when it you put it standing up.

As for emergency dialing, most of you should have learned to have a UPS in the house for the computer. If you do, they will have plenty of charge for your phone in case you need it but yes, you are right.

George


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## Quension (Jan 27, 2010)

Magic Matt said:


> One thing I've never understood... the main complaint with these type of phones is you can't use them if you have a power cut because the base station requires power from the mains, meaning in a power cut a cheap standard phone works and the fancy one doesn't. Why isn't there a backup battery in the base station so you can still phone out in an emergency?



At least AT&T and Uniden have hybrid models -- the base has a corded handset attached, but supports cordless handsets. That way it works exactly like a classic corded phone during power outages. The last Uniden 5GHz model I tried 3 or 4 years ago was a bit disappointing in technology though; the base worked well enough, but it was not possible to customize ring tones etc on the base, only the satellites. The ring was electronic; it's not like it's impossible to intercept the signal when the processor's powered and default to the line-powered ring circuit during an outage :scowl:

Occasionally I drift over to the phone section in whatever store I'm at to see what's new, but nothing has caught my eye yet. I'm still annoyed at the button layout on half the satellites these days. It didn't even occur to me until this thread that I could do better with batteries in some of them though; I'll have to pay more attention to the Panasonics next time I'm browsing.


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## PeAK (Jan 27, 2010)

dannstrait said:


> I've had a Panasonic KX-TG9361B for about a year and half now. I posted my initial comments about the phone in this thread as referenced by Peak in post #48.
> 
> I have a few thoughts I think will be helpful.
> 
> ...



This is just a guess on my part but I think part of the mystery of the Panasonic charging algorithim (older models) can now be stated based upon the two observations/experiments made by Dann. 



Batteries with a known capacity (550mAh) are being used in a device with known a charger current, the charger basically times a charge (*counts up* to 7 hours) from a reset condition (i.e. time=0) that can be caused by a change of batteries. This would work out to 118mA based upon 66% charge efficiency (7*118mA=1.5*550mAh).
When the handset is used (not standby), the counter now counts down from three bars at a rate based upon the handsets power/current consumption (might not be 118 mA) until the "zero count" OR the unit hits low voltage point. You are then advised to place the handset in the cradle.
If you happen to place the handset back in the cradle, then the unit continues to time/count up until FULL.
So if you use larger capacity batteries, you may not see any benefit. If you leave the phone on standby (i.e. off the charger), the battery may run down but the display *may* show more charge than it really has. Of course, this might be accomodated by having the counter slow its "count down" but that might be too expensive to implement    Regardless, I think it might be a way to prolong the life of NiMH batteries and maximize the number of charge cycles.


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## Bright+ (Jan 29, 2010)

So, my Philips CD445 came with 750mAh AAA batteries that test to full capacity on MHC9000 at 100mA discharge after being charged in handsets. 

It has a problem with premature low battery warning and as I said earlier, it can not be ignored, because it beeps in the earpiece every minute. It prematurely drops to low battery with as much as 1.27v and capacity test showing 500mAh remaining. 

I might have to return this phone.


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## Mr Happy (Jan 29, 2010)

Phone definitely seems defective.


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## guiri (Jan 29, 2010)

It would drive me nuts.


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## Bright+ (Jul 14, 2010)

So, something really strange. The Philips phone I mentioned a few posts ago uses a pair of 750mAh NiMH AA, however the internal resistance is high, so when I activate the speaker phone on the handset at high volume, it shuts off.

I tested the capacity to be about 750mAh, about the same as Rayovac 4.0 AAA.

I replaced the batteries with Rayovac 4.0 and it would never stop charging and stay in trickle perpetually (which will kill the batteries quickly) 

With the batteries that came with the phone, charging gets finished (the battery indicator stops moving)

With Rayovac 4.0, the charge indicator won't stop and battery stays hot.


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