is it safe to charge lithium ion in series?

[mesojin]

i have 2 psp batteries with 3.6 volts each and 3600 mah, i have a portable dvd player that uses and charges 7.4 volt batteries with 3600 mah... can i charge the psp batteries if i connect them in series? or would they leak/ blow up?

[tom61]

I'm not really sure, but I wouldn't attempt it. I believe that the cells need to be impedance matched, same as in parallel charging.

Lithium is highly reactive, if it comes into contact with water (including the limited amount in the air) it will catch fire. So, leak equals fire.

[samjc3]

i seriously doubt it. in theory, the batteries for the portable dvd player should have and internal charge protection circuit. if you just hook the psp batteries up, they will probably asplode.
however, if you were to hook up a PCB, its possible it could work. but, why not just get a smart charger? or just use the psp to charge these batteries? what are you even trying to do with them?

[mesojin]

well im using the psp batteries to power my portable ps2 (the newest scph 9000 ps2 takes 7.5 volts) by putting them in series. im getting 10 more from ebay for 40 dollars (with shipping) and i only have one psp to now charge 12 batteries....

[samjc3]

well im using the psp batteries to power my portable ps2 (the newest scph 9000 ps2 takes 7.5 volts) by putting them in series. im getting 10 more from ebay for 40 dollars (with shipping) and i only have one psp to now charge 12 batteries....

wait, the new ps2 uses 7.5? MUST HAVE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[mesojin]

yea, its perfect with the psOne screen... but i think i just broke something .... god damn it..