Need battery advice

[D. Abineri]

While waiting for my EG4 6000xp, and doing the wiring prep, my cells are down to 3.29 v in my diy 48v LiFePo battery having been just balance by my Neey active balancer during this time.

Does this mean that I should top balance the pack again before starting up the 6000xp?

Thanks for your advice on this.

 

[sunshine_eggo]

While waiting for my EG4 6000xp, and doing the wiring prep, my cells are down to 3.29 v in my diy 48v LiFePo battery having been just balance by my Neey active balancer during this time.

If the balancing drew the cells down to that level, you have the balancer set incorrectly. It should not balance below 3.40V

Does this mean that I should top balance the pack again before starting up the 6000xp?

Not necessarily, but you should charge to more conservative peak voltage, like 3.45V/cell and ensure the balancer is given enough time to bring the cells into balance.

 

[740GLE]

So at one point not to long ago you had all cells at 3.5-3.6v? Ie full then you let them sit since then and now your noticing the resting voltage is 3.29v.

How long has it been since top balance?

I’d say leave it until you commission the system and place the battery in service. If you have any unbalancing in your first charge, use the balancer that’s what it’s there for.

IMO top balance only gets you that last 5% of capacity so it’s not critical unless every whr is life dependent.

 

[D. Abineri]

If the balancing drew the cells down to that level, you have the balancer set incorrectly. It should not balance below 3.40V



Not necessarily, but you should charge to more conservative peak voltage, like 3.45V/cell and ensure the balancer is given enough time to bring the cells into balance.

But they weren't being charged since the inverter had not arrived, that's why they dropped. Thanks.

 

[D. Abineri]

If the balancing drew the cells down to that level, you have the balancer set incorrectly. It should not balance below 3.40V



Not necessarily, but you should charge to more conservative peak voltage, like 3.45V/cell and ensure the balancer is given enough time to bring the cells into balance.

Yes, but they weren.t being charged without the inverter. Thanks

 

[time2roll]

With a NEEY active balancer all cells will stay in balance. Assuming the balancer is still connected just place in service when EG4 comes in.

 

[D. Abineri]

So at one point not to long ago you had all cells at 3.5-3.6v? Ie full then you let them sit since then and now your noticing the resting voltage is 3.29v.

How long has it been since top balance?

I’d say leave it until you commission the system and place the battery in service. If you have any unbalancing in your first charge, use the balancer that’s what it’s there for.

IMO top balance only gets you that last 5% of capacity so it’s not critical unless every whr is life dependent.

Thank you, this is probably what I will do.

 

[D. Abineri]

So at one point not to long ago you had all cells at 3.5-3.6v? Ie full then you let them sit since then and now your noticing the resting voltage is 3.29v.

How long has it been since top balance?

I’d say leave it until you commission the system and place the battery in service. If you have any unbalancing in your first charge, use the balancer that’s what it’s there for.

IMO top balance only gets you that last 5% of capacity so it’s not critical unless every whr is life dependent.

Thank you, good advice.