3S/2S Battery Charger with TP4056

Hello,

I am trying to build 3S and 2S compatible battery charger. I have these TP4056 single cell battery charger modules. But i can't understand how to build it. I see its possible to charge batteries in series but i don't know how to handle balancer socket.

I build 3S battery pack and balancer socket like this

And TP4056 Modules like this

But ended up with over voltage levels, obviously first charger gets 3S voltage second 2S voltage third charger 1 voltage.

Modules Battery GNDs and Supply Voltage GNDs common this is the problem i think.

Update

I think i found what i am doing it wrong. Charger Modules' GNDs need to be separate. I can do that, but then i will need 3 separate power source, can it done with just 1 power source?

These charger modules work by charging cells , switching off charger then using balancing module to discharge. This process is repeated continuously until all cells are balanced and charged. At least thats how mine works.

Your modules are designded for single cells. They have to be wired seperatly you cannot use the balance connector.

If you need all the batteries to charge simultaneously then you can try blocking diodes on the ground lines. But this could affect the charge level do to voltage drop on diode. If you can charge batteries at different intervals then use relays to sequence one charge at a time.

I do not see how that would work. If you use series lipos they have to be charged is series. Balancing gets the voltage to the worst cell.

Any other arrangement risks destroying the lipos

Update

I can charge with balance socket now i connected like this:

But power source of TP4056 Modules' must be separate.

@spicetraders How can i use Diode?

Guys I will let you know if I get success. Now They are charging from each separate 5v power supply, its going to take time. Each cell should stop charging at 4.2V. I have 1n4148 diodes but i cant figure it out how to connect them. Can you help me how can i power this from single 5v power source?

You cant. If you use them in series you have to charge them in series so a 3s charger will require 3 x4.2 v plus a bit supply.12.6 v plus. Also you do not have a balancing circuit , your lipos will not last very many cycles this way.

I can't understand, what balancer do is to get each cell to 4.2 V (in this situation) doesn't it?

You charge in series. The balance connector is used to discharge during the charging processs. The circuit is sequential not a simple linear circuit. If you wish to use seriers connected lipo batteries i w would suggest a commercial charger. If you wish to experiment , buy eye protection goggles. If charging in series do it outside. Google on lipo charging methods before you try. These batteries can be dangerous if not charged correctly

omersiar: I can't understand, what balancer do is to get each cell to 4.2 V (in this situation) doesn't it?

Not exactly.

A worn out cell may not get to 4.2 v Thats an off load measurment anyway which may not correctly indicate the state of the cell. When connected in series a duff cell could take out the whole stack. Series connected lipo batteries can fail spectarctularly..

What the balancer does is discharge all the other cells to the same level as the worst one in the stack. The balancer measures each cell individually.

Thank you,

Conclusion

This is not the best way to charge Lithium batteries in series, charging possible with 2 extra DC/DC isolated converters, which is ridiculous. If every cell at good condition they will charge to charger's default charging cap (TP4056 tries to get 4.2v). But these cheap ICs not good at it, and you will end up un-balanced battery block, which will cause batteries quickly wear out. Not efficient, nor safe. Do NOT risk trying to do that. Simply get Lithium charger with balance.

They have a really nice 60W unit out for $30 or so. I have one and it does 1S thru 6S.

http://www.ebay.com/itm/iMax-B6-Digital-LCD-RC-Lipo-NiMh-Battery-Balance-Charger-accessories-US-Stock-/130935654729?pt=Radio_Control_Parts_Accessories&hash=item1e7c5f8949

Beware of fake clones of the Imax B6 - which could set your house on fire.

http://bit.ly/1rGz9q4

// Per.

Oh eff. Iv got one of those. Used in a charge hut though. Any links ?

Boardburner2: Any links ?

http://bit.ly/1rGz9q4

// Per.