Lithium battery 1 large vs multiple

[mrgscooter]

I'm seeing some large 200ah or 300ah lithium batteries recently. Is there any issue with a single 300ah battery vs. 3- 100ah batteries? In both cases, I can fit them in my battery bay.

[DavidEM]

I would go with one big battery. Simpler and with a single BMS not two.

David

[The_Breeze]

I'm going with what he said. In a multi-battery install, the new way is to use a bus bar to spread the load amongst all batteries instead of wiring them together and then meeting up with the pos and neg connections. Otherwise, the 'head' battery takes most all the charge/discharge activity while the others hardly participate.

This may help you: https://diysolarforum.com

[16ACE27]

A single battery is great.......until one cell dies and you have to replace the whole battery.

[Chance]

Originally Posted by mrgscooter

I'm seeing some large 200ah or 300ah lithium batteries recently. Is there any issue with a single 300ah battery vs. 3- 100ah batteries? In both cases, I can fit them in my battery bay.

Look closely at specs to compare the single larger battery’s BMS maximum current rating against your maximum anticipated load.

Often a single 300 Ah battery (particularly the more affordable ones) has a BMS that is not rated at much higher current than a 100 Ah battery.

If your current/power demands are not very high, a single battery can save a little cost and or space. Single large batteries seem to be growing in popularity, but I’m certain their max current rating is high enough to handle inverters or whatever manufacturers are powering with battery. For example, if BMS is rated (limited) at 200 Amps, that may not even power 2,000-Watt inverter at full load.

[ducksface]

Multiples with isolators.
One is none.
And
There are other expensive components to consider for lithium.

[Chance]

Originally Posted by 16ACE27

A single battery is great.......until one cell dies and you have to replace the whole battery.

Yeah, though some batteries can be disassembled and serviced. It’s possible in some cases to replace a bad cell.

Also, larger capacity batteries have multiple cells in parallel, and then those groups in series. I’m not sure if BMS would detect one bad cell within a parallel group. For example, a 100 Ah battery may have 4 cells in series. A 400 Ah may have the same size cells in 4X4 configuration.

[Judge]

I installed four of the Big Battery 170Ah OWL LiFePO4's. They are great...

- They have the most Ah per dollar that I could find
- They each have their own BMS
- They each have an On / Off Switch
- They can be serviced
- They have a 10-year warranty

They just came out with this new stackable space saving model that looks pretty cool but not as many Ah for the price that I paid for mine.

https://bigbattery.com/products/12v-...138ah-1-76kwh/