Tripling storage capacity

[Nesto514Rides]

I have a lifepo4 battery that i use in my converted RV. The battery is an Ampertime 12v 200ah 100Amp BMS. I am interested in at least doubling if not tripling the capacity and i am planning on building the next two batteries. My plan is to build two 12v 200ah batteries but my question is with the BMS. If the new batteries have each a 120Amp BMS, how will charging and discharging be affected when they are connected to my existing battery? TIA.

 

[Rocketman]

Won’t be an issue. Just connect the batteries together properly - either to a battery bus bar with equal length/size cables or positive on one side of the bank and negative on the other.

 

[chrisski]

I don’t think it will be an issue.

You just need to plan to make sure the smallest BMS is not exceeded when the discharged. For planning, just assume the amperage will be equally spread amongst the batteries. I asssume your ampertime BMS is 200 amps, but the other one or two is 120 amps, so 120 amps X 3 is the amount of wattage you can push.

I think this is around 3600 watts. IMO, if you are anywhere near that, time to go up to 24 volts.

In my signature block, there is a link and math to figure the best way to hook the batteries.

 

[Nesto514Rides]

I don’t think it will be an issue.

You just need to plan to make sure the smallest BMS is not exceeded when the discharged. For planning, just assume the amperage will be equally spread amongst the batteries. I asssume your ampertime BMS is 200 amps, but the other one or two is 120 amps, so 120 amps X 3 is the amount of wattage you can push.

I think this is around 3600 watts. IMO, if you are anywhere near that, time to go up to 24 volts.

In my signature block, there is a link and math to figure the best way to hook the batteries.

The ampertime BMS is 100Amps but my goal isn’t to push more amps but to extend my time range. I may push higher amps in the future but based on my past experience I think it’s highly improbable I would use more than 50amps at any one time.