maemo.org - Talk - Battery Tests, Homemade 3000mAh XL Battery & Q&A (POST #1)

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- - Battery Tests, Homemade 3000mAh XL Battery & Q&A (POST #1) - New Layout (https://talk.maemo.org/showthread.php?t=65568)

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A

Quote:

Originally Posted by cantruchd (Post 983977)

I think there's not much difference in those as the length is very short (<1cm), I used solder wire because it was available and it is more 'bendable' (means that if you bend it it will stay bended and not revert to it previous shape), and the diameter/thickness of the solder wire is just right (not easily get off the batts. and not hard to push in).

I just measured solder wire and no there are no 'resistance' so it can be used, i would however just use thick wire that have been striped bare and soldered so it becomes more stiff then solder wire, and then using pliers to shape it correctly to fit, if you don't have thick wire (1mm) then use several stands of thin wire, twist them together and solder, again fix them to shape needed.

Quote:

Do you know if there is anything wrong with the charging management in PR 1.3? mine never charge to 4.2V, so dr_frost_dk's script never show 100%. Could it be possible that the system compare the resistor's mAh(A) to the mAh being charge(B) and when B > A then it just stop charging?
Any idea?

Normal USB charging stops at about 4.15V-4.18V so no you will never see 100% on my meter or the meter in the phone, my external charging system takes it to 4.23V, a small tweak in the code of my meter can make it display 100% at 4.15V but then it will not be truly accurate since the limit is for LiPo/Li-Ion is 4.23V

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A

My scud update. Moderate phone usage. Very limited internet usage (checked mapquest for directions a few times). Driving all day today with signal dropping from 3.5 down to nothing and back numerous times. I just hit around 60 hours of uptime, and my N900 just started making the 'help me I'm about to die' sound. I'm perfectly happy with 2 plus days without having to recharge. Once again this is with a single battery, not the dual-battery mod.

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A

Due to resistance between charger chip and battery+system, the voltage at full battery (but before end of charge) will be 4200mv - system_load * .128 Ohm. Or in other words, the higher the power use, the lower the voltage will be.

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A

Here is a photo my my version of the cantruchd version.

I used 1.5mm copper wire, split it in two and twisted it. i didn't have any soldering equipment handy so this is just bent into place, seems to hold very well.

had to place the second battery slightly further back or the Mugen lid wont go on.

http://www.abload.de/img/batt_modbyeq.jpg

Thanks again for the third time :)

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A

Quote:

Originally Posted by shadowjk (Post 984498)

So should we do some heavy work on the phone to "trick" the charger think that the voltage is low so it continue to charge until 4.2???. I will test it :-)

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A

More good results with a single Scud, and autodisconnect enabled (3G only when internet is used, otherwise GSM mode), I put a fully-charged battery (from external charger) in my N900 about 28 hours ago, and I have not charged it since then. It still has 10% remaining capacity according to battery monitor.

Really much better than with original Nokia battery. :)

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A

cant wait to get mine. its a few days away

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A

Quote:

Originally Posted by cantruchd (Post 984610)

So should we do some heavy work on the phone to "trick" the charger think that the voltage is low so it continue to charge until 4.2???. I will test it :-)

No, heavy work results in lower voltage.

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A

Hi all,

I would also like to us cantruchd's method for my scud batteries.

Can someone tell me what solder wire or wire to use ? Is there a specific type ? Or as long as its width 1mm its ok ? I will use the Nokia 1200 mAH charger for charging - does this mean I need some specific type of solder/wire to use ?

Also, do you just bend the wire into the following U shape

____
|____

and just fit it into the terminals of the 2 batteries ? You do not need any hot soldering or adhesive ?

Apologies but all I see is a photo and just wanted to be sure there is not a step I am missing.

Re: Battery Tests, Homemade 3000mAh XL Battery & Q&A

Hi dr_frost_dk ,
i stumbled upon this scud 1700mah. could this be tested please? or has it already been tested? thanx :(