Originally Posted by Milo1952
I understand how close in weight & size BB & Relion are, but the Expion
is 15-20 % smaller and some how packs more cells into a smaller space,
I need one of the electrical engineers to explain this to me. The Expion also delivers 1000 less cycles as BB.
Might be a different chemistry and use smaller form factor cells. Or might not have an integrated BMS reducing battery height.
AM solar sell the expion and battleborn - you could give them a shout and ask.
For lithium ion, you pretty much get what you pay for. Cheaper packs (not necessarily less expensive, just cheaper construction) donít have the same cycle lifespan nor can you charge or draw at the same currents as higher end packs. That may or may not matter given your intended use and desired lifespan.
Victron who use Winston prismatic cells pretty much set the standard in my opinion. But you pay for it and they are a bit heavier and require external BMS, adding complexity to the install.
Battleborn are next best in my humble opinion and probably deliver the best bang for the buck.
The expion360 rated at 120ah only has a max 80A discharge rate. Thats less than 1C. Thatís concerning in my opinion as it speaks to cell and construction quality. But again, that limitation may be fine for your install and use.... battleborns are rated right at 1C discharge rate. So 100ah battery can be discharged at 100A continuous.
Victron by comparison can be safely discharged at 2C or 200A on a 100ah battery. This is helpful / pertinent with high demand applications like running your air conditioner through a 3000w or 5000w inverter. But once again - may not matter for your intended use.
Finally none of these packs allow for 100% discharge. Battleborn de-rate their packs - they actually put 120ah of cells leaving about 100ah available before the BMS cuts off discharge. They rate the battery at 100ah evening though actual capacity is greater.