Question about , lipo's amps, and fast chargeing

[pinkpanda3310]

When I was trying to learn about lipo's I had heard of them exploding during charging but that was from using the wrong charger (nimh) or trying to charge dead or disfunctional cells. I haven't heard of someone deliberately charging more than the C rating.

Originally Posted by snellemin

The FMA can balance and charge at that same high amp rate. Like I said, you have to try the FMA to believe the true high speed charging. The A123's get charged at 20A now. That is limit of those cells.

One or two of my A123 packs were make up's from disfunctional dewalt packs so they have mixed resistance and life cycle (yes, I know, my bad ). Didn't think it would matter that much 'cause of the relatively safe chemistry. There still going strong

What I would like to know is how does the FMA keep up the charge rate on unbalanced packs when the balance tap is only good for 2 amps?

[snellemin]

Originally Posted by pinkpanda3310

What I would like to know is how does the FMA keep up the charge rate on unbalanced packs when the balance tap is only good for 2 amps?

FMA does it at 3 amps.

Based on my observations, the resistance of the cells go down when you start to pump amperage into your packs. The higher the CC the lower the resistance.
My Acepow get out of balance below 3.7V per cell. When I have 3% capacity in the 4s pack the cells are out of balance, but during charging the the cells voltages match up again at 3.7V per cell. So in a way it self balance itself out at that point. Now once it goes into CV the amprate drops but then your pack in near full and it's just topping it off.
The top off time is a tad longer with me charging at 4.1V per cell cutoff, which comes out to around 91% capacity.

The one thing I don't like of the FMA setup, is the power cables with the blade fuses. Those little fuses get stupid hot at 40A. I added heatsinks onto them. You don't see that everyday.

[feistyacorn]

Originally Posted by snellemin

I added heatsinks onto them. You don't see that everyday.

Thats awesome! Can we see a pic?

[snellemin]

Originally Posted by feistyacorn

Thats awesome! Can we see a pic?

Here is a iphone pic





Whenever these fuses go, I'll upgrade them again.

[feistyacorn]

Originally Posted by snellemin

Here is a iphone pic

Whenever these fuses go, I'll upgrade them again.

Snellemin... that looks hilariously awesome!