[Q] BenQ E72 battery hacking?

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Hi!

Long ago, I owned a Benq E72 that my wife washed out. I tried to dry it up and it worked for a while. Then it died...but I never threw it out :P I just had the feeling that it was the battery.
You see,the phone or accesories are not sold where I live nor I have a way to purchase online, so I tried to hack every single battery that laid on my hands.
Last night I got a generic mp4 battery to power up the phone, but it turns out I cannot charge it .
If the "SERVICE" pin on the battery is not making contact, I get an "invalid battery" message after about 30 sec of charge and it stops. Otherwise the error reads "battery temperature too low,aborting"
As you can imagine I can not spend anytime checking the unit so I am asking you if you know how can I either force the unit to ignore the battery status or fake whatever temp the unit needs on the battery.

Thanks in advance!

If you still have the old battery, try to get that charged with a charger that is not caring about the temperature sensor (simple universal 2-pin LiIon charger). It may just be that the E72 is too sensible.

If that does not work, then cut it apart and replace the circuitry of the original one with that of a replacement battery. Chemically there is hardly a difference and only the protection unit and access to the temperature sensor is different for each battery. More advanced (or bigger) batteries may even have digital circuits built in to identify the battery (like in a laptop), but for mobile phones I guess that things are quite simple.

Be warned: Messing with circuit protection may get the battery on fire or explode, so only do that if you know how to supervise the first full charge.

Hi tobbie! Thank you so much for the reply.

I still have the original battery but I am not sure if it will hold a charge.
When the phone got washed, I spent an hour tearing the unit apart and drying it up but forgot about the battery. Then I realized my mistake.
I dried it up and it worked for a couple of hours. Then the phone started to go off on its own.
It got to the point where if you hit the power button, the SMS and power LEDS start blinking non stop, like it tries to go on but can't.
I will do some more research on your tips, they are quite helpful!

Thanks again

You should really be sure that no whatsoever residues are left in phone after the washing (and drying) process. I would take apart the phone completely and clean all parts of it from e.g. left over detergent.
It is much more probable that the phone has a damage than the battery. Circuitry in the battery is quite robust compared to the complex electronic in the mobile phone.

My battery died almost a year ago, since that I'm using something practical but not very appropriate

I used a Samsung AB553446BU (3.7v 1000mAh battery) and a pair of thin wires. Following the polarity of the pins on the phone, I put the Samsung battery and secured it with a piece of paper. As I said before, it's not appropriate but it really does its job!. If you can not solve your problem, try to do something similar if you get a battery that is compatible with the BenQ E72, the battery I'm using has given me no problems I can even charge it from the phone without having to use a universal charger. I'm not having "Invalid battery" messages or "High/Low temperature" warnings.

But as tobbbie said, "It's much more probable that the phone has a damage than the battery".

Oh wow! tobbie AND nickleby helping me in the same thread, what an honor!
I did exactly what you did nickleby! But mine is not that fancy, more like thin copper wire taped to the battery :P
The phone seems to be OK, I left it overnight and it did not go out (when the old battery dried up and worked, it will stay on for no more than 4-6 hs).
I am 100% sure the phone and battery are dried and clean, the "incident" happened at least 3 months ago.
I am pretty sure I can get your battery model for a few bucks right where I live.
Although I currently own an android tablet, I really miss having my WM smartphone

One more time, thank you guys for all the help!!

Getting the Samsung battery prooved to be impossible.
I was not able to find a 1000mah samsung compatible battery in the whole city.
I did however found 960mah batteries that were compatible with the same models.
Originals were almost as expensive as a basic phone, so I opted for a Chinese knockoff which I just managed to install.
The original charger won't charge it, neither will some other chinese USB chargers, but a USB port is doing the job just fine.
I am so happy to have my WM6 phone back
I was using an LG kp110 which I accidenally fried in a pool, and had to use a Siemens A31 for more than a month!
Thank you guys!