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AC Charging problem with original charger & new battery

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!

anyone? :''-(

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

kecido said:
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
Click to expand...
Click to collapse
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

Charging anomaly, workaround
vbJoe said:
...Now I plug my original charger (5v 1a) into the pda and the charge light turns on ..
Click to expand...
Click to collapse
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?...
Click to expand...
Click to collapse
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,

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.

Very small wall charger

Do you think this will work with the Kaiser?
http://www.brightonnet.co.jp/english/product/ipod/bi-plugac.html
It is a very nice piece of hardware ! I know there are similiar products out there, but this small factor make it unique.

Probably won't work too well with the Kaiser, as it delivers only 600mA; the Kaiser can demand 1000 mA. So if the Kaiser's battery is significantly drained, this charger couldn't provide enough current to charge it, especially if the unit is turned on.
Look for chargers that supply 5 volts at at least 1000 mA (or 1A).

Charger drains BATTERY!

Hi guys,
I have really huge problem! When i connect my htc tytn to charger ( wall charger or usb, same thing) it drains battery ! There is orange light like it is charging, but it goes from 100% to 0 in an hour! Battery works fine... 2 - 3 days... and because i can't charge it over usb, i am using nokia charger, cut the wires, took battery out and connect + to +, - to - and that's how i charge it for the last few days! Does anyone has any idea why is this happening? I have wm 6.1 pays rom i think it is 3.05

Fire Hazard
i warn angst doing this as this could over charge the battery and when a Lithium Iron or Polymer is over charged they burst into flames or explode and spread nasty toxic chemicals every where. if this be the case it may be time to try a new rom and see if that fixes your problem, try someone elce's charger if this wont fix your problem it may bet time for a new mainboard as these have the charging circuit built in
lithium rechargeable are compact high energy storages devices, and if not charged properly become dangerous

I had charging issues with my 8125 - it would charge with the charger, but when I unplugged the charger (it would read 100%, say I charged from 52% to 100% or something), it would drop really low to like 25% or 23% - sometimes it dropped all the way, and I could no longer get the battery to charge because my travel charger was 500mA and the original charger was 1A - it didn't have enough power.
I had to give it a boost by using a 9V battery and twist ties - touching the battery like you are doing here. I did it for 15 seconds a couple times, popped it in, and it had enough juice to start charging. However, I wouldn't want to do this too long on it as the battery got warm pretty quick and I saw a glimpse of smoke at one point.
After being cautious and not letting it lose charge all the way again, after a few charges it seems to have improved. It no longer drops battery power when unplugging and seems to work as it should.
Not sure if yours drops when you unplug it like mine was, or if it steadily drains while plugged in. Anyways, I thought my charger was just wacked, but it is working fine now after a few charges and being careful and keeping a close eye on things....I also thought it was the battery, but I ordered a new OEM battery, popped it in, and when I unplugged the charger that battery dropped and lost power as well. Now I have two batteries and both seem to work ok, but I did have to play around with them a lot and it did take a few charges before they started working like they should again. I'm not sure what was going on, because it couldn't have been the battery (I replaced it with a new one), and now the charger is acting properly.
Granted, this is all with an 8125 which is older, but there may be something in common here. All I know is it does seem to be fixed and it didn't require any additional purchases or replacements.

sounds like the charging circuits are wacked, this could be caused by dry joints on the charger "smart" chip, but a little heads up with Li-Ion, they don't like gettin wet, (sweat included) once they have been wet they become a fire hazard, (ultramag69 help me out here, remember that one you gave me that was full of mud?!?).
they also don't like going below their threshold voltage of 2.1v per cell, (i think 2.1 for now) after that the battery becomes a resistor and is not worth trying to shock back into life with a 9V battery, as these have a protection circuit built in, as well once in this state they become another fire hazard, it may be worth buying a cheap $30 butane soldering iron with surface mount attachment and just going over some of the areas located round and on the opposite side of the battery, every thing under the silver covers is RF shielded and not worth trying to reflow.
just don't keep the heat on too long, as you may and will desolder components on the opposite side of the board.
other than that if the charger is giving +5 volts respective to its ground, its fine, the difference between the 1A and 500mA chargers is the rate at which its charges the battery, slower is better for Li-Ion due to battery construction for the life span of the battery (if you get more than 6 months out of one your doing good by manufactures standards)
heck even try checking the phones USB connector, it may be stuffed or shorted

[Q] Solar charging for Nook Touch

I've got hold of a solar panel that outputs 5v at around 350-450 ma. I was reading up on Li-Poly batteries (the Nook touch has Li-poly AFAIK) and I am concerned about this bit:
http://en.wikipedia.org/wiki/Lithium-ion_polymer_battery
LiPoly batteries must be charged carefully. The basic process is to charge at constant current until each cell reaches 4.2 V; the charger must then gradually reduce the charge current while holding the cell voltage at 4.2 V until the charge current has dropped to a small percentage of the initial charge rate, at which point the battery is considered 100% charged. Some manufacturers specify 2%, others 3%, but other values are also possible. The difference in achieved capacity is minute.
Balance charging simply means that the charger monitors the voltage of each cell in a pack and varies the charge on a per-cell basis so that all cells are brought to the same voltage.
It is important to note that trickle charging is not acceptable for lithium batteries; Li-poly chemistry cannot accept an overcharge without causing damage to the cell, possibly plating out lithium metal and becoming hazardous.[5] Most manufacturers claim a maximum and minimum voltage of 4.23 and 3.0 volts per cell. Taking any cell outside these limits can reduce the cell's capacity and ability to deliver full rated current.
Most dedicated lithium polymer chargers use a charge timer for safety; this cuts the charge after a predefined time (typically 90 minutes).
Click to expand...
Click to collapse
So does anyone know if the Touch has intelligence built in on the device side for charging? I assume it does since you can connect to PC USB for charging. I'm hoping this is the case so I don't have to get some funky circuit between the panel and the nook to charge it on the road.
Any advice would be appreciated!

Yes, the Nook Touch has (as every electronic device which gets charged over a normal wall wart or USB) a builtin charging circuit.

I've been thinking of doing this; attaching a panel to the back and soldering onto the USB for a (hopefully) neater solution than using something external which puts pressure on the USB port

Just use a portable solar charger with a regular USB output port.
---------- Post added at 06:06 AM ---------- Previous post was at 06:06 AM ----------
There are actually quite a few out there to pick from if you look on amazon.

I have a "Power Monkey explorer" solar charger and it works, but it really isn't that great. It takes 8 hours of strong direct sunlight to charge the battery pack, which has a 2100 ma AA battery and then you plug this into whatever you want to charge. There is plenty of sun in the summer to charge it if I left it outside, but it really is a pia. I ususlly charge the battery pack from my computer and use it to charge my nook or cell phone when traveling if I need to. Hotels are really bad about putting electrical outlets in the rooms and shut the power off when you leave the room (any plastic card works to fix that problem).
I really don't think I would solder anything to the nook, you could do some major damage and the sun really isn't that relaible in most places. Also attaching a solar panel to the back of a device that would be damaged by excessive heat is asking for trouble. You would have to leave it in the sun for long periods of time and it would get hot. Plastic also degrades much quicker in direct sunlight so you would be damaging the case over time.
It is much better to use one of the kits with a battery pack for the above reasons and if it is a good kit it will have several adapters to you can charge a variety of devices. Unfortunately they are very expensive, I saw the one I have in Brussels for 79 euro last week. I got it for 10 euro as a promotional deal, and I wish I had bought all they had so I could sell them on e-bay.
If you are trying to save money on electricity, it will never work. I'm not sure where you live, but in the US, 1KWH Kilowatt hour (1000 watts for 1 hour) costs less than $1.00, although California is expected to be much higher. The battery on the touch is 1530mAh x 110v = 168.3 Wh, lets call it 200 with the conversion loss on the wall wart, so you can charge it about 5 times for less than $1, probably more like 10 because you rarely do a full drain and the cost is much less than $1. The solar charger I have is $89 on amazon, so you have to do between 100 and 200 complete charges before you broke even. However beacuse of the battery life, unless you really used it a lot, you most likely would never come close to breaking even. At half the projected battery life it would take about 10 years of only using the solar charger.
Don't get me wrong, I think Solar is great, but it is priced way too high to be practical. The charger I have probably costs less than $20 to manufacture in china, it sells for $89. Honestly, I think it would be cheaper to buy batteries and charge it from them than to use one of these small solar chargers, definately if you bought the batteries at Ikea!
I'm waiting for Horizon Fuel Cell Technologies, they have some really interesting stuff. In my opinion a solar powered fuel cell system is the way to go, certainly on a large scale. Still too exensive for small scale, but very cool. I've seen a house with a solar/fuel cell system completely off the grid. Large house, heat/ac, big frige and freezer, NO BATTERIES. Works great. Biggest problem I think is replacing or testing the storage tanks every 15 to 20 years.

FloydF said:
The battery on the touch is 1530mAh x 110v = 168.3 Wh, lets call it 200 with the conversion loss on the wall wart, so you can charge it about 5 times for less than $1
Click to expand...
Click to collapse
Uh, the NST battery is 1530mAh sure, but it's only 3.7V so that would give it a more realistic total of 5.66Wh
The number of charges on a single KWh would be 176 (a little less as you need to account for losses in the charger and charging circuit.)
Now charging the NST from a solar cell small and flexible enough to fit the back of the NST would still be a PITA .. it will take ages, even in direct sunlight.
And, as Floyd points out, you really don't want to expose the dark back of the NST to direct sunlight, it will get insanely hot and degrade the plastic.
If you really need solar charging for your NST, something like this might be a more realistic option.

[Q] Make this tablet USB rechargeable ?

Hi I bought what I believe to be a Wopad V7+ ..
The ac/dc power supply broke and it's tough to find a compatible plug (very tiny) ...I'm waiting for a hopefully compatible charger to be shipped...
The tablet is officially not rechargeable/powerable via the micro-usb but I wondered if someone could point me to a (noob-friendly) way/HACK to make it rechargeable or at least powerable via USB ?
I can't post external links but I know it's powered by 5v 2A and you can find the pictures/information at dealextreme. sku104916 or at wopadusa.com store It seems to be AKA: HAIPAD M8 /Zixoon V78c / McPad V7+ / MOMO 1000 (BUT Resistive touchscreen)
You can see the internal components on a youtube video v=8SiLWpLCfus
there is pics of internal on twitpicDOTcom (/photos /bjlandsberger)
OR THERE : chinadigitalcommDOT com (/ haipad-m8-vimicro-vc882-t10830-10 DOT html)
or http twitpic DOT com ( /6i0ouo/full )
These pics/video aren't mine as I didn't DARE to open mine.
I apologize if my english makes your eyes bleed. Any help is welcome

USB can't provide 2A of current you'll have to buy a new charger
Sent from my X10i using XDA App

nugget1993 said:
USB can't provide 2A of current you'll have to buy a new charger
Sent from my X10i using XDA App
Click to expand...
Click to collapse
that shouldn't matter. It would still charge, just much slower. Just cut open the charging wire and a USB wire. Find which wire is positive and negative on your charging wire. connect the red usb wire to the positive wire in the charging cable. Connect the black wire to the negative wire. Insulate. It should charge.
Note- if you switch the wires, you can permanently screw up your tablet.

This. Just be extra sure not to cross up your wires, I did this once with a USB hub and fried the board. It literally left melted plastic on my desk.
Epic_VS said:
that shouldn't matter. It would still charge, just much slower. Just cut open the charging wire and a USB wire. Find which wire is positive and negative on your charging wire. connect the red usb wire to the positive wire in the charging cable. Connect the black wire to the negative wire. Insulate. It should charge.
Note- if you switch the wires, you can permanently screw up your tablet.
Click to expand...
Click to collapse

It's a 3.7v battery which means it can charge at 5V. Looks dooable with a .5A Regulator and a 1ohm resistor... I'd try this and if it fails, then you've tried and failed

So it is a 3.7 but the problem is that is a raw battery pack as in no protection, no regulation, no charging circuit. If you want to sit there and babysit you could attempt to put 5.0V on the power lines and that might work. I would say it is dangerous to do so.

Epic_VS said:
Connect the black wire to the negative wire. Insulate. It should charge.
Note- if you switch the wires, you can permanently screw up your tablet.
Click to expand...
Click to collapse
No risk of fire/explosion ? What would be the best way to insulate ? heat Shrink tube + tape ?
I planned using a ACDC inwall 110 to USB 5v 1A out adapter, would it be risky ?
Will I have to babysit it to prevent a fire ???
Errrr...
.5A Regulator and a 1ohm resistor.. Maybe with a graph and picture I could figure how to do it ... I don't know anything about electronic/tension ohm's law.. I don't want the battery to explode and rip my head apart.

No matter, go for it, it will be OK, all li-ion batt used in mobile device have a small protection circuit in it(unless specified) ur batt too have it, use heat shrink tube, a 100-300ma USB current can't make it explode.
Sent from my HTC HD2 using XDA App

moto xoom...
Hmm....is this possible to do? If so I would like to try it on my Xoom, the little pin charger is annoying I bent the hell out of it. Micro USB would be stronger . All pros no cons.

For the most part putting 5V on a 3.7V load is not overly dangerous. In order for you to charge a battery, the voltage being applied to the battery has to be greater than the potential storage of the battery. In this case, greater than 3.7V. My blackberry charger is 5V regulated output.
We use 3A power supplies all the time to charge 12V batteries. The voltage we set it to is 14V. These power supplies aren't smart. They just dump current. The higher the voltage pf the battery gets, the lower the current gets as it starts to resist the current that is coming into it. Even your cars alternator puts out 14V and yet the car battery is 12V. For the most part, the actual voltage of batteries is 10%-15% higher than what it is rated at as well. So your 3.7V battery is more like 4.05V - 4.20V when it has a full charge.

But, this is not going to give much big problems. As the current is only 10-20% of the original batt amp, so it will be ok, but for high current ratings the voltage must not be more than 1-1.5 v higher than the batt voltage.
More over the ditachable batt of most phones /pda have inbuilt i-v regulator inside the batt. It will prevent overcharging and deep discharging on most cases.
Sent from my HTC HD2 using xda premium

WOW thanks a lot for the informations, if my RMA doesn't go as I want I'll probably settle to try this and keep this post updated.
Thanks a lot. XDA is great.
My two other (unanswered) threads:
http://forum.xda-developers.com/showthread.php?t=1477288
http://forum.xda-developers.com/showthread.php?t=1480517