balance charging ?

[Str8V8ping]

I was wondering .Does anyone have any idea for balance charging 7.4v li-po cells ? I would like to do a mod like this but cant think of a way to balance charge them without a external hobby charger. I would like to keep it internal and balance charge from a usb wallwart. A 3.7v li-po would be simple to add a usb charge circuit internally but im using a stepdown regulator so i need a 7.4 lipo.

My prime choice would be finding a way to make a balance circuit internally ran off a usb wall adaptor

Second option although id rather not have to do it is have it charge in parallel and have a switch back to series.

last option would be to find a small cheap external balance charger thats accurate and have balance charge ports on the mod. This is last resort since i would only be able to charge if i had the balance charger.


On another note for single batt mods i will go with this wall adaptor
http://www.ebay.com/itm/USB-2A-AC-H...?pt=US_Tablet_Accessories&hash=item1e6d932617
and a internal 1A usb charge circuit.

 

[Str8V8ping]

Nobody ....................................

 

[slimest]

If you purchase two usual AC-DC adapters with 5V outputs and two charger boards like this: universal 1A lithium battery cell liion li charger board module In4.5-5.5V #243 | eBay, you can make balancing charger, just connect chargers outputs in series. Very easy.

This is even smaller: http://www.ebay.com/itm/universal-1...45593?pt=Battery_Chargers&hash=item2573074299

 

[Str8V8ping]

If you purchase two usual AC-DC adapters with 5V outputs and two charger boards like this: universal 1A lithium battery cell liion li charger board module In4.5-5.5V #243 | eBay, you can make balancing charger, just connect chargers outputs in series. Very easy.

This is even smaller: universal 1.5A lithium battery cell liion li charger board module In4.8-6V | eBay

I can charge them that way but how would that keep the cells balanced ?

I was thinking maybe a balancing circuit out of a laptop if i could find one that works with only 2 cells.I would think laptops would have a balancing circuit inside since they are usually use multi stacked cells

 

[breaktru]

It's not a balancing charger but it has protection: 2 Cell Charger/Protection

 

[MadmanMacguyver]

hey str8 just make ur mod w a balance connector to link to the MUCH BETTER hobby charger...Trust me one more cable to plug in is no big deal...I have been doing it w my personal CBatt mod for 8 mo...of course I get like 5-6 days from the 26500s I use so I really have less fuss...lol



Much safer too most decent hobby charger truly turn off after completing a charge cycle

also when using properly rated batts w good solid connections in the batt holder there is really very little isse w balancing...before I added the balance connector to the design it went 6 mo w/o no need to balance the batts...at least if you are internal charging and have built in protection in the mod...(and I don't mean a ptc fuse...I use actual 2 cell series protection boards)

and I got one of these for kicks to check out the balance function...they are prohibitively HUGE!!!!!

 

[Str8V8ping]

hey str8 just make ur mod w a balance connector to link to the MUCH BETTER hobby charger...Trust me one more cable to plug in is no big deal...I have been doing it w my personal CBatt mod for 8 mo...of course I get like 5-6 days from the 26500s I use so I really have less fuss...lol



Much safer too most decent hobby charger truly turn off after completing a charge cycle

also when using properly rated batts w good solid connections in the batt holder there is really very little isse w balancing...before I added the balance connector to the design it went 6 mo w/o no need to balance the batts...at least if you are internal charging and have built in protection in the mod...(and I don't mean a ptc fuse...I use actual 2 cell series protection boards)

and I got one of these for kicks to check out the balance function...they are prohibitively HUGE!!!!!

For a personal mod id have no prob just using my hobby charger and be done with it or going without balancing but I cant make other people need to buy hobby chargers though and with the lipo batts being internal and not user replaceable i would need to keep the lips's in balance for longevity.