I need a battery for my selfmade catamaran. It´s a smal boat (2x4m). For this a Li-ion battery with 700Wh is big enought.
Step 1: Choose a Battery Box
I bought a batterybox from aliexpress. It´s for 60 pcs. 18650 cells.
Watch the Video. It Shows a cheap box for only 45$. You can use it also for an e-bike.
Step 2: Lithium-ion Cells
Buy good Li-ion cells. I chosse 60 pcs. Panasonic NCR18650B cells. 10 parallel an 6 in series.
The result: about 700Wh