Revive exhausted battery?

Well, I've managed to solder two of the batteries together but NOT using copper wire. Just trying the third battery (tricky) now

What I did for one case was simply to with the copper wire to loop around the tabs from ends of two batteries. Then secure it by taping them up with an electric tape. It works anyway! ... After all, thousands of electronic devices also have bare metal contacts without solder. ... AND ... if we think of it, the external batt case/housing has metal contacts that just *touches* the metal contacts of the device! ...

The only reason I can think of why these cells are soldered is because these cells are in batteries, whose cases are sealed and non (user) serviceable, hence they are soldered to prevent non-contact when dropped or something.

To be honest there is so little room in the battery pack housing that any extra wire/solder will mean that the cells will not fit back in. I think the three cells all make contact with one another without any solder but they also have to be soldered to the PCB in FOUR seperate places

In my previous rebuild attempt it must have been just one of these joins which wasn't done well enough as the battery would indicate charging (ie the charging status LED would blink but the battery would not actually be charging).

I AM going to rebuild this successfuly today no matter what it takes . I'll let you know how I get on. Oh and thanks Snappy for your words of encouragement and support!!

Edited by lextre 2005-06-05 7:06 AM

good luck!!

lextre, hope you get sucess with it this round! ... and let us know the results ...

say ... you interested in LCD panel modding?
See my other thread on it

You should try buying an external charger and removing the batteries from the pack and charging them in that. This is easily accomplished by desoldering one of the battery wires to the circuitboard or connector and then clipping both leads to the charger.

On another note, BE CAREFUL!!!

http://www.rcgroups.com/forums/showthread.php?t=209187

!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I have personally exploded a LiPo, and it was a small one (350mAh) and it was quite violent. The pakcs you are trying to modify are under more pressure (hard cases as opposed to sleeved), have MUCH higher energy and will explode EXPONENTIALLY more than some of the ones on the link. Be careful gosh darn it!!!! Dont just poke around with the soldering iron!!

hey.. what to do then when soldering a battery?
how did you manage to explode your li-po? i'd like to know.. so that i can avoid doing it in the future

Heat. Do not overheat a li-ion battery. Two most common ways this is done and explosion is the result is: 1) improper charging than results in overheating 2) soldering something directly onto a li-ion battery and overheating it.

Be sure you understand Li-ion batteries before you tinker with the electronics or attempt to solder wire or leads OR remove soldered leads or wires.

For a detailed responsible instructions on how to rebuild a NEC 770/780 battery pack go to Rich Hawley's fine piece at: http://hpcnec.com/battery.htm

To get authoritative education about nature, use, proper care and working with li-ion batteries see: http://www.buchmann.ca/newarticles.asp

---Bruised

Has anyone heard of placing the Lion in a freezer for a few days to revive it? I read that in several places and maybe it has merit.

What would freezing it do? Realign the chemicals? Completely discharge the charging circuit so it can then charge properly? any ideas?

I will be re-working my Clio C-1050 batteries, going from 4x 20500 size ?mAh batteries to 2x 18650's at 2400mAh.... Should increase the lifespan of the awesome machine. I dont know the specs of the old batteries, but the new ones will acheive 7.2v@2400mAh and weight much less doing so. Anybody have any suggestions?

Just as bruised said before: DO NOT OVERHEAT THEM. you'll know when you're doing it. when they get hot, just let them cool down, maybe get a fan near, but don't get them into the fridge, because they don't like abrupt changes. Also, if you can get batts with solder tabs on them, do it; they'll make your life much easier.

Hope this helps

btw, when you find a source for those 20500 size li-ion cells, let me know ya? I need 4 of them too!

I mistaken the Clio batts to be based on 3 X 18650 cells, so now I am stuck with 3 of them. ... oh well...

Seems this is over but for future reference:

1. You do need a solder with flux, radio shack or parts store should have it. Sometimes these tabs even then are not easy. Some times if you sand them slightly with fine sandpaper it will ruffen and allow solder to take hold. The tabs need to be good and hot also normally. (flux cleans the surface)

2. Freezer. Supposedly keeping regular batteries in veggie drawer will keep them longer, doubt freezer would help a dead one unless it caused a bad connection to repair itself for awhile.

3. These batteries just die at times, not related to anything in particular.

4. If you have a batteries plus store in your area they can spot weld the tabs together for you (if they will do it - might cost you a few bucks). They also might have batteries you need, no I don't work for them, just use there services now and then