charging bl-5c | bl-6c

Michael Shiloh michael at
Fri Feb 15 20:31:28 CET 2008

Mike (mwester) wrote:
> Michael Shiloh wrote:
>> Playing the devil's advocate for our hypothetical legal department,
> Ah, *those* folks; the same ones who processed the gllin drivers?  :-p  :-D


>> shouldn't we only charge batteries that we have tested against and 
>> know the charging curve for, so that we know we won't overcharge and 
>> potentially cause the battery to explode? For this reason (I suspect) 
>> all cellphones look for the ID of the battery, and if it's not the one 
>> they were designed for, they refuse to charge.*
>> Granted, this is an extremely paranoid point of view, and is not mine. 
>> Besides, since our source is open, nothing prevents anyone from find 
>> the code that does that test, and bypassing it.
> Or better still, finding that code and replacing it with code that would 
> recognize the alternate batteries and changing the charging limits and 
> parameters as appropriate -- that to me would be the true essence of 
> openness.

Yes, agree completely. And perhaps that's what will happen, now that a 
phone exists that is sufficiently open.

>> Assuming, of course, that this is the reason we do not charge BL-5C 
>> and BL-6C.
>> Michael
>> * Another reason is that the cellphone maker would have you buy the 
>> expensive battery from them, rather than the cheaper knock-off 
>> replacement from Radio Shack or whatever.
> You'll pardon me for believing that this latter reason is almost 
> certainly the true reasoning for the current cellphone makers.  I think 
> that if the industry wished to do so, they could all have agreed on a 
> safe fall-back set of defaults that all devices and batteries could 
> accommodate safely (even if sub-optimally).

I agree completely. I think the legal reason is just the justification 
they use.

> If there is a u-boot or other software thing going on, I think it would 
> be big marketing statement if OM could offer support for other vendor's 
> batteries as a built-in, standard "openness" feature...

I'm no expert on this, but I think the charging and discharge curves for 
the battery in the real device need to be studied in order to create the 
appropriate parameters. I don't think it's a simple test of measuring 
voltage and current when charging is complete. But again, as the project 
moves forward, perhaps there is a way for the community to measure these 
things with a wide range of batteries and provide this data.

>> Michael 'Mickey' Lauer wrote:
>>> Hi Andy,
>>> do you think there is a way to enable charging for the Nokia BL-5C 
>>> and BL-6C batteries in the GTA01/02? They work fine, but for some 
>>> reason our PMU does not want to charge them in the device.
>>> :M:
> Mike (mwester)

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