LIFEPO4 Battery discussion thread

[cavedog]

So went and fetched the battery. This is also a pacebms exactly like my original battery. QH Tech. It has 355 cycles about 1 year old and the bms says it has roughly 91Ah capacity left so probably a cell imbalance I need to correct.

Flipped the dip switch and immediately detected in my setup. Nice. Now I have 2 x pacebms batteries and not sure what the new ecoo battery bms is.

Tomorrow its mounting, wiring and fusing day.

 

[cavedog]

So went and fetched the battery. This is also a pacebms exactly like my original battery. QH Tech. It has 355 cycles about 1 year old and the bms says it has roughly 91Ah capacity left so probably a cell imbalance I need to correct.

Flipped the dip switch and immediately detected in my setup. Nice. Now I have 2 x pacebms batteries and not sure what the new ecoo battery bms is.

Tomorrow its mounting, wiring and fusing day.

View attachment 1909512

Guy sold it to me for R6000. He dropped the price from 10k to 6k because no one wants to buy it because its not compatible with other batteries I think its a win for me.

 

[wingnut771]

So went and fetched the battery. This is also a pacebms exactly like my original battery. QH Tech. It has 355 cycles about 1 year old and the bms says it has roughly 91Ah capacity left so probably a cell imbalance I need to correct.

Flipped the dip switch and immediately detected in my setup. Nice. Now I have 2 x pacebms batteries and not sure what the new ecoo battery bms is.

Tomorrow its mounting, wiring and fusing day.

View attachment 1909512

Now if I can only see this screen at 56V, I'll jizz in my pants.

 

[cavedog]

Now if I can only see this screen at 56V, I'll jizz in my pants.

Okay tomorrow I will charge them up and take voltage readings.

The new battery battery 2 is still very unbalanced. 112mV imbalance at what the bms thinks it 100% SOC. I have been struggling to get it to balance. It doesn't want to.

 

[wingnut771]

Okay tomorrow I will charge them up and take voltage readings.

The new battery battery 2 is still very unbalanced. 112mV imbalance at what the bms thinks it 100% SOC. I have been struggling to get it to balance. It doesn't want to.

Balancers in these things are very small, in the mA range, so even a few Ah will take days, and some balancers only balance when its charging which takes even longer if ever. I have hope though seeing bat 1 managed to balance I assume.

So with bat 2 (or any bat with the highest cell volts), watch cell voltage and stop when highest is at 3.5V and use that pack voltage as your new bulk/float, then hopefully the 112 will come down over time, then repeat process until you can reach 3.5x16=56V.

Maybe it needs 3.55V (56.8V) to start balancing? I don't know.

 

[wingnut771]

Okay tomorrow I will charge them up and take voltage readings.

The new battery battery 2 is still very unbalanced. 112mV imbalance at what the bms thinks it 100% SOC. I have been struggling to get it to balance. It doesn't want to.

Just screenshot this at 56V, not 52.4V:

 

[DTBA]

So went and fetched the battery. This is also a pacebms exactly like my original battery. QH Tech. It has 355 cycles about 1 year old and the bms says it has roughly 91Ah capacity left so probably a cell imbalance I need to correct.

Flipped the dip switch and immediately detected in my setup. Nice. Now I have 2 x pacebms batteries and not sure what the new ecoo battery bms is.

Tomorrow its mounting, wiring and fusing day.

View attachment 1909512

can you log into the battery with pbms software?

 

[DTBA]

Guy sold it to me for R6000. He dropped the price from 10k to 6k because no one wants to buy it because its not compatible with other batteries I think its a win for me.

Saw the facebook add for R7000

 

[DTBA]

Balancers in these things are very small, in the mA range, so even a few Ah will take days, and some balancers only balance when its charging which takes even longer if ever. I have hope though seeing bat 1 managed to balance I assume.

So with bat 2 (or any bat with the highest cell volts), watch cell voltage and stop when highest is at 3.5V and use that pack voltage as your new bulk/float, then hopefully the 112 will come down over time, then repeat process until you can reach 3.5x16=56V.

Maybe it needs 3.55V (56.8V) to start balancing? I don't know.

I want him to log into the battery and check on it normally its set 3.400v and 30mv diff

 

[wingnut771]

I want him to log into the battery and check on it normally its set 3.400v and 30mv diff

3.4 is too low and can cause imbalance.

 

[cavedog]

can you log into the battery with pbms software?

Saw the facebook add for R7000

Yes I told him I have 6k is he willing to take that and he said yes.

I haven't tried the pacebms pc software but the app works as expected for what it is.

 

[DTBA]

3.4 is too low and can cause imbalance.

What I see happens a lot is they set the charge voltage to 58.4v, the battery hits OVP so fast that it has zero chance to balance

 

[DTBA]

Okay tomorrow I will charge them up and take voltage readings.

The new battery battery 2 is still very unbalanced. 112mV imbalance at what the bms thinks it 100% SOC. I have been struggling to get it to balance. It doesn't want to.

does the new ECCO also have dip switches?

 

[wingnut771]

What I see happens a lot is they set the charge voltage to 58.4v, the battery hits OVP so fast that it has zero chance to balance

Thats why I said to stop pack voltage when highest cell reaches 3.5V and wait for it to balance, then repeat and increase pack voltage to new highest cell 3.5V voltage and wait to balance etc etc.

 

[cavedog]

does the new ECCO also have dip switches?

No it does not. I don't pick it up on bluetooth either but specsheet says it has wifi and bluetooth like my original ecco but so far I could not get it connected so I'm doubting if it's a pacebms

 

[DTBA]

Balancers in these things are very small, in the mA range, so even a few Ah will take days, and some balancers only balance when its charging which takes even longer if ever. I have hope though seeing bat 1 managed to balance I assume.

So with bat 2 (or any bat with the highest cell volts), watch cell voltage and stop when highest is at 3.5V and use that pack voltage as your new bulk/float, then hopefully the 112 will come down over time, then repeat process until you can reach 3.5x16=56V.

Maybe it needs 3.55V (56.8V) to start balancing? I don't know.

First of the pacebms did only balancing when charging >< the new version does atleast always balance when its not discharging.

Also like you said passive balance on them suck balls.

JKBMS 2amp active balancer is nice,

 

[wingnut771]

 

[cavedog]

Okay the imbalance is worse that I thought. I might need to remove it from the pack and see if I can balance it separately. It disconnected due to low cell cutoff but the highest cell is still 3.278

 

[DTBA]

Okay the imbalance is worse that I thought. I might need to remove it from the pack and see if I can balance it separately. It disconnected due to low cell cutoff but the highest cell is still 3.278

View attachment 1909575

give it a charge today and see when the other cells hits ovp how bad the cells are

 

[cavedog]

give it a charge today and see when the other cells hits ovp how bad the cells are

Looks like only 1. Cell08.

All the others are pretty close to each other for now. Will have to see at 3.65v after resting a bit.