Charging lipos in parallel

[fabiograssi]

Is that possible?

If the answer is positive, the correct way to connect the packs to a 6s charger is aything like:
- power wires: connect + with +, and - with -, and then connect to the charge wires of the charger;
- balance wires: connect 0v from pack1 to the 0v from the pack2, connect 3,7v from pack1 with 3,7v from pack2, and like that successively, and than connect this in the balance connector of the charger

Something like the image in attachment (just balance wires)?

 

[TPA]

I asked that question as well and got directed to the turnigy thread. They touch on the subject there, but do not go into a full tutorial on how things are connected up.

Short answer is yes it is possible, you have to buy pigtails, to do what you describe above (I think, I'm still trying to verify so I will not blow myself up).

Start at the middle of this page:
http://endless-sphere.com/forums/viewtopic.php?f=14&t=10817&start=165
and read about 2 more pages after that, then come back and reassure me that I am not about to make a big mistake. :lol:

 

[Anonymous]

.

 

[Lessss]

I had thermal runaway on lipo doing parallel charging experiments in the past.

with what chemistry manufacturer?

 

[AussieJester]

Yes you can you can charge them in series too if your brave and know what your doing.

This article Will be of help to you...As nutsandbolts said though don't leave them unattended in a place you wouldnt be happy having a flash fire in case something goes wrong, the majority of Lipo fires happen during charging.

KiM

 

[liveforphysics]

See that balance tap 4 into 1 harness? Thats what I leave connected to 20Ah packs. I make 8-1 harnesses for the 40Ah packs. LiPo should be left in parallel at the individual cell level at all times if you are going to run parallel cells.

 

[AussieJester]

Luke is that an old picture you had on file? I ask because i see a Sentilon Turnigy ESC there, was that one you fried or replacement for one(s) you fried? 12mhz model? I wish to use the Sentilon initially to get me going and would be interested in buying the pictured ESC if it is for sale and not needed? Let me know anywayz Luke (i wont be finacial for a month or so if you could hold on to it?)

KiM

 

[Anonymous]

.

 

[liveforphysics]

It's a way old picture. I've decided those controllers aren't up to the task Otherwise I would send it to you

 

[AussieJester]

No probs Luke thought i would offer prefer paying you money than somebody i don't know at Hobby City...I will have to make do with the Sentilon for the time being i can afford the alternatives anytime soon.

Cheers anywayz

KiM

 

[fabiograssi]

...LiPo should be left in parallel at the individual cell level at all times if you are going to run parallel cells...

Dear liveforphysics, I don't understand this expression... How can I do a "parallel at individual cell level"?

I intent to run 4 x 6s 5000mah 22.2v turnigy in 44.4v and 10000mah setup (12s2p).

But I simple don't know how can I charge this pack in this configuration.... So, the question on this thread is part of a bigger question, something like "How non-engineers can buy, charge and discharge a turnigy 12s2p 44.4v 10000mah in their e-bikes????" :lol:

 

[liveforphysics]

Tie all the balance taps together for each group of cells you have in parallel. Leave them together always. Charging and discharge. That's the best way to do it, and it is the most simple way to tie the cells at the individual cell level. You can either make custom harnesses for the balance tap connectors like i showed in the picture, or you can cut and solder them together.

 

[fabiograssi]

Tie all the balance taps together for each group of cells you have in parallel. Leave them together always. Charging and discharge. That's the best way to do it, and it is the most simple way to tie the cells at the individual cell level. You can either make custom harnesses for the balance tap connectors like i showed in the picture, or you can cut and solder them together.

So, in this case, the solution will be:

- make the connections like described in the balace wires, leaving like this forever;
- connect the power wires of two packs in parallel too, leaving like this forever too.

It makes a 6s2p pack.

Make the same thing with the two other packs, and then you have two 6s2p packs.

Buy two balance chargers that can handle with 6s cells, and charge each build pack (6s2P) with one charger.

For use, connect this two packs (6s2p) in series, making a 12s2p pack, and connect something (hobbycity stuff) in each balance connector (two) that can read the lvc of the individual cell (more precisely each of two cells connected in parallel) to monitor the discharge.

Something like this setup is at least a little bit safe to do?

 

[Anonymous]

.

 

[Olavi]

Tie all the balance taps together for each group of cells you have in parallel. Leave them together always. Charging and discharge. That's the best way to do it, and it is the most simple way to tie the cells at the individual cell level. You can either make custom harnesses for the balance tap connectors like i showed in the picture, or you can cut and solder them together.

So, in this case, the solution will be:

- make the connections like described in the balace wires, leaving like this forever;
- connect the power wires of two packs in parallel too, leaving like this forever too.

It makes a 6s2p pack.

Make the same thing with the two other packs, and then you have two 6s2p packs.

Buy two balance chargers that can handle with 6s cells, and charge each build pack (6s2P) with one charger.

For use, connect this two packs (6s2p) in series, making a 12s2p pack, and connect something (hobbycity stuff) in each balance connector (two) that can read the lvc of the individual cell (more precisely each of two cells connected in parallel) to monitor the discharge.

Something like this setup is at least a little bit safe to do?

You are following correct path, you can even charge two permanent 6s2p packs in parallel with a single charger, check this guide http://www.rcgroups.com/forums/showthread.php?t=932319

When batteries are in uneven charge state before connecting them together, then they will have the same voltage, when connected in parallel, but I would check the voltages first, maybe the difference is way too high.

NB! Always double check, before connecting disconnected wires to avoid mistakes or you could get burned fingers.

 

[liveforphysics]

Tie all the balance taps together for each group of cells you have in parallel. Leave them together always. Charging and discharge. That's the best way to do it, and it is the most simple way to tie the cells at the individual cell level. You can either make custom harnesses for the balance tap connectors like i showed in the picture, or you can cut and solder them together.

So, in this case, the solution will be:

- make the connections like described in the balace wires, leaving like this forever;
- connect the power wires of two packs in parallel too, leaving like this forever too.

It makes a 6s2p pack.

Make the same thing with the two other packs, and then you have two 6s2p packs.

Buy two balance chargers that can handle with 6s cells, and charge each build pack (6s2P) with one charger.

For use, connect this two packs (6s2p) in series, making a 12s2p pack, and connect something (hobbycity stuff) in each balance connector (two) that can read the lvc of the individual cell (more precisely each of two cells connected in parallel) to monitor the discharge.

Something like this setup is at least a little bit safe to do?

Sounds perfect. I connect groups of 4p and 8p soldered through the balance taps and power leads to make permanently connected 20Ah and 40Ah 6s packs that connect together to make 12s, 18s, or 24s packs for discharge.