AC Charging problem with original charger & new battery

[vbJoe]

Hi!

I had a battery probelm (same one everyone else seemed to get with there 1yr old uni) where it cuts out at 60% due to the voltage from the battery dropping below the threshold really fast.

Anyway I got a new battery .. my old one was 1650ma (or something like that) I got this new one which is 1750ma (or something like that).. definitely different.


Now I plug my original charger (5v 1a) into the pda and the charge light turns on .. I leave it for an hour and the battery hasn't charged any.. in fact its lost charge as you'd expect if it had been left switched on with no supply.

So.. I plug my motorola krzr charger (5v 550ma) into it and go for a shower/sh*t/shave come back and the battery has gained 10%.. great! atleast I can charge it now.

I also have a desktop cradle charger (5v 1a), same problem.. it sits there forever and a day and discharges... no charge.. (I only got it when I got my new battery so could not prove it before hand)

USB charging works with no problems (not from the cradle one though). So my question is ... Why?

Could it be something to do with my new battery?? I got it from PDAAddons and they've always been good in the past so I believe I can rule out it being a fake.

My new battery is a Li-on Poly.. I've got to admit I didn't look at my old one to see if that was a poly too ... was definitely a li-on though.

I can live with using my moto charger on my exec but unfortunately the ac adapter for my cradle is of a different connector type (female pin sleeve thingy like nokia) so before I search the world for a 5v 550ma version I could do with knowing if i'm barking up the wrong tree and about to waste my money..


Any electronics whizzes in the house say ho!

[vbJoe]

anyone? :''-(

[kecido]

Aahaahaa!

I'm here! Now, what you say sounds very interesting and yet very strange, why?

- Normally more current from the charger should be better, you cannot put in the PDA more current than it's factory maximum (which I don't know how much it is, but that's not a problem), the internal charger (inside the PDA) knows how much it is and how to limit, also takes care of the right charging profile for your battery.

- You don't have to worry about the exact battery type you bought, boths are Lithium, so chargind profiles are mostly the same, these (LiIon and LiPoly) are "exchangeable" usually (I've heard of no problems until now, since several years I mean).

- If your battery is discharging means only one thing, you're not puttin current into the battery, you're taking it out of it! So, either you might have a deffective charger, a deffective charging circuit (the one inside the PDA) or a defective battery.

- You can charge the battery with your Moto's charger, so battery is probably ok, you have used your original charger/craddle until now, so they might be ok, you have charged one battery at least to 10% so PDA should be ok.
What can it be?

Possibilities are:
Slightly deffective PDA's internal charging circuit, the fact that you can charge with a lower rating charger (the one for your Razr, thing that I've done myself two weeks ago), might point to this, because you have already "limited" the maximum current to 550mA (Razr's charger max current).

Slightly different battery, most of the batteries do have some kind of thermal protection circuit inside (chip + temp sensor, etc.), if the behavior of this circuit is not "compatible" somethin strange can happen, however I personally consider this option not to be the best.

One or two of your chargers might also be somehow "deffective", why? Your original battery might be ok and you are just having problems with your chargers or your High capacity chargers (the original one and that from the craddle) have some problem to give enough juice to your batteries.

I surely might proceed as follows:
try to charge both batteries with a stand alone charger, this is not an easy task, because Lithium batteries are the most "delicate" types, charging method is the "strangest" one, I have two stand alone battery chargers that came as gift with some Nokia batteries I bought from an Ebay seller, eventually, I could give you the full schematic so you can construct it (if you want and if you can).
In this way I will not have any more suspects from the batteries.

Second, test each of my chargers, it can be done by connecting a medium -and suitable- load to each charger for some minutes.
A wire wound ceramic resistor should do the trick, ie for the Razr charger (5V, 550mA) I could use a 250mA load, R=V/I, so 5V/.25A equals 20 ohm (1.25W max power, use at least a 2W resistor, 3 or 5W better).

If the internal PDA circuit should be defective, take it to fix or try to fix for yourself.

Hope this helps

[vbJoe]

Aahaahaa!

I'm here! Now, what you say sounds very interesting and yet very strange, why?

- Normally more current from the charger should be better, you cannot put in the PDA more current than it's factory maximum (which I don't know how much it is, but that's not a problem), the internal charger (inside the PDA) knows how much it is and how to limit, also takes care of the right charging profile for your battery.

- You don't have to worry about the exact battery type you bought, boths are Lithium, so chargind profiles are mostly the same, these (LiIon and LiPoly) are "exchangeable" usually (I've heard of no problems until now, since several years I mean).

- If your battery is discharging means only one thing, you're not puttin current into the battery, you're taking it out of it! So, either you might have a deffective charger, a deffective charging circuit (the one inside the PDA) or a defective battery.

- You can charge the battery with your Moto's charger, so battery is probably ok, you have used your original charger/craddle until now, so they might be ok, you have charged one battery at least to 10% so PDA should be ok.
What can it be?

Possibilities are:
Slightly deffective PDA's internal charging circuit, the fact that you can charge with a lower rating charger (the one for your Razr, thing that I've done myself two weeks ago), might point to this, because you have already "limited" the maximum current to 550mA (Razr's charger max current).

Slightly different battery, most of the batteries do have some kind of thermal protection circuit inside (chip + temp sensor, etc.), if the behavior of this circuit is not "compatible" somethin strange can happen, however I personally consider this option not to be the best.

One or two of your chargers might also be somehow "deffective", why? Your original battery might be ok and you are just having problems with your chargers or your High capacity chargers (the original one and that from the craddle) have some problem to give enough juice to your batteries.

I surely might proceed as follows:
try to charge both batteries with a stand alone charger, this is not an easy task, because Lithium batteries are the most "delicate" types, charging method is the "strangest" one, I have two stand alone battery chargers that came as gift with some Nokia batteries I bought from an Ebay seller, eventually, I could give you the full schematic so you can construct it (if you want and if you can).
In this way I will not have any more suspects from the batteries.

Second, test each of my chargers, it can be done by connecting a medium -and suitable- load to each charger for some minutes.
A wire wound ceramic resistor should do the trick, ie for the Razr charger (5V, 550mA) I could use a 250mA load, R=V/I, so 5V/.25A equals 20 ohm (1.25W max power, use at least a 2W resistor, 3 or 5W better).

If the internal PDA circuit should be defective, take it to fix or try to fix for yourself.

Hope this helps

I'm gunna buy another 5v 1a charger .. I've had it reported that this cradle charger (5v 1a) doesn't work properly anyway so it may be 2 seperate problems here :-) Thanks for you advice fella :-) much appreciated

[gibhenry]

...Now I plug my original charger (5v 1a) into the pda and the charge light turns on ..
Are you absotively, posilutely certain the AMBER charge light comes on fully?

I leave it for an hour and the battery hasn't charged any.. in fact its lost charge as you'd expect if it had been left switched on with no supply.

So.. I plug my motorola krzr charger (5v 550ma) into it and go for a shower/sh*t/shave come back and the battery has gained 10%.. great! atleast I can charge it now.

I also have a desktop cradle charger (5v 1a), same problem.. it sits there forever and a day and discharges... no charge.. (I only got it when I got my new battery so could not prove it before hand)

USB charging works with no problems (not from the cradle one though). So my question is ... Why?...

There is some anomaly about charging with a plug-in charger. You may have to turn the device on so that it can recognize the charger, then close it and let it turn itself off; or perhaps it's turn it off then on, I'm not sure, but I've encountered similar oddities with both 110v, 220v, and 12v chargers, and I've seen discussion about this anomaly on this and/or other fora. Once you get the AMBER light, you're fine (as long as it's putting out at least +5v; +5.5 is better).

I think it has something to do with its looking for a [non-existent] USB signal along with the voltage under some conditions, but not others, but that's just a wild guess. Anyway, I don't think there's necessarily anything wrong with your battery, device, or charger. Hope this helps. Cheers,

[vbJoe]

Thanks for the reply, I'm 100% that the amber light turns on. Not only that the screen brightens so it definitely knows its connected. I've tried several combinations of turning it off/on etc during the charge/before but nothing seems to make this desktop charger actually put anything in the battery.