So, I’m seriously considering building a DIY battery. Watched Will build a few on YouTube and it looks like fun, and a good learning experience. A while back Will built a 12 volt, 200 amp hour battery with Fortune cells and a Overkill BMS. The 8 cells cost about $960 ($120 each), and the BMS another $142, which totals $1102. The Overkill BMS also has Bluetooth and a great app. Then I saw him review an SOK 12 volt, 206 amp hour battery - which he highly recommended - at a cost of $1029. In that review video he states “you can make your own battery for much cheaper”. I’ve also seen many other YouTube videos where this is stated as well. So, I’m a little confused, and am probably missing something very obvious. Am I comparing apples to apples? Can someone please shed some light on this subject. Thanks!!
I can share what I'm doing. I just built one of these a week ago (although with grade B cells). The finished results are quite nice, and prompted me to order 3 more of the battery kits.
First, grade A cells:
4pcs Eve 280ah Lifepo4 (lfp) 3.2v Cells Battery (new Version Lf280k With 6000cycles,Fully Matched)--genuine Grade A - Buy Eve lifepo4 luyuan Product on Alibaba.com
szluyuan.en.alibaba.com
Yes, I'm sure you can order grade B cells for much cheaper. I'm going with grade A myself.
Amy has quite a long thread here, and delivers what she says she will.
Battery box kits (they actually sale everything you need):
Sun Fun Kits DIY LifePo4 Lithium Battery Kits & Ready Made AGM / Lead Acid Replacement Batteries for RV, Golf Carts, Solar Storage, Back Up Power, Hurricane Outage . Made in Baton Rouge, LA, USA Ready to Ship out no overseas delay! Sunfunkits.com
www.sunfunkits.com
JBD 150 amp BMS (you don't actually want to run your cells above 0.5C or 140 amps).
Smarter Shopping, Better Living! Aliexpress.com
www.aliexpress.com
The ones with grade B cells I'm giving to my grandson and sister along with an
MPP PIP – 1012LV-MS, cables, some cheap 100 watt panels, etc. Especially my daughter/grandson have had power outages from hurricanes, and that should keep the fridge and TV running for them.
For myself, I'll probably use grade A cells and put a few in series for a 24v all in one.
A 280AH battery at 12v with a quality BMS is nothing to sneeze at, especially since you can run those BMS in series. Add matched grade A cells, and I suspect that even in series they will stay balanced quite nicely.
I have no financial interest in anything, I'm just very pleased with the quality of everything I've linked here, and would highly recommend them.
Edit to add, I'm going to check and see if the EVE 304AH cells will fit, or if they have plans for a plate to make them fit.