Reviving a dead and really hard to get BB battery

[soulaiman]

Hi to you all of Dave's crazy followers,

This is my first post so please be kind. I have a background in IT and everything that has something to do with that but not so much with electronics. I mean... I can repair smartphones but not like understanding how a battery works chemically for example.

Anyway this is my problem.

I've got a BB Passport and if you follow the smartphone market you'll know that not many people actually have got one of these. For this reason parts are a) expensive and b) almost impossible to get something other than the LCD.

A while back I replaced the LCD in this thing and had to remove the battery to get acces to it. To do this I heated it up from a distance with a hair blower on medium/low. After replacing the screen, the phone actually still worked for a day because it had more than 70 percent of charge left. However after returning it to the owner and after the battery was dead, it refused to charge. I think the battery got really low and protected itself from powering up again (this is comon with Blackberry's).

Is there any way without some expensive PSU's that I don't have to boost the battery back up and wake it up ? Or do you guys have any sugestions ?

If yoy want to see the details of this battery, here is a link: http://tweakers.net/aanbod/789313/blackberry-passport-batterij-accu.html

Thanks guys

[Pillager]

You could try hooking it up directly to a LiPo-charger, and see, if that helps.

[brainwash]

I 'revive' most of these batteries by hooking them up to a current-limited and voltage-limited power supply.
If you don't have one, use 2-3 AA/AAA batteries, they should provide enough current limiting. Basically, you don't want to get above 4.2V and 1C (in your case 3400mA). Once the battery voltage raises above 2.8V-3.2V it can be charged in-phone. By using 3 AAA batteries, the voltage of those will drop below 4.3V as the LiPO is soaking up energy. I think most non-rechargeable AAAs have a maximum current around 400mA and 1000mAh capacity.

You should not leave any of these setups unattended, the LiPO might decide to draw a lot more current and/or heat up.

Source: I've done this more than 20 times with LiPOs ranging from 100mAh to 20000mAh. If the battery is swollen you need to dispose of it, it's on its way to dying.

[mikerj]

Some lithium polymer cells have a built in protection circuit that may prevent you charging the cell if it's voltage is very low.  In this case you'd have to bypass it.  If the cell voltage has dropped below about 3.0v, then you must charge at a very low current until the cell voltage is up to around 3.0v or so, something like 0.05C would be ok.

Obviously don't leave it charging unattended.  Low voltages can damage cells internally and make them more prone to interesting failure modes.

[amyk]

The only somewhat unusual feature I see about that battery is a max voltage of 4.35V - if you do manage to revive it, see what voltage it gets charged to; it might be only 4.2V (and that 4.35 is an "absolute maximum") in which case you can replace it with a standard lipo cell of the same size. If it's actually getting charged to 4.35V, then "high voltage lipo" are somewhat rarer, but still available:

http://www.highpowertech.com/product_096ffc299200f517.html