I’m interested in building a power wall for home use. Typically you see lithium-ion batteries up to 14s for use in ebikes and all kinds of low-voltage DC applications. For home use you want 220V AC (or 110V AC for Americans).
An inverter would waste a lot of energy going from 12V to 220V at high wattages. The lower the voltage, the more amps are drawn and thus more energy becomes waste heat. You also need thick wires to not have them become fire hazards. The battery also gets strained when drawing high amps from them.
Would it be sensible to build a 60S battery? Transformation losses from 240VDC-> 220VAC should be quite minimal. You can put enough solar panels in series to make charging this battery sensible as well.
Of course there are obvious safety hazards with high voltages but there should be advantages as well, lower strain on battery cells and minimal DC->AC losses.
To add to this, a lot of large scale batteries also have built in safeties in addition to the battery cells. So even if you don’t shock yourself, you could burn down your house from a bad battery cell.
Indeed. Batteries require a BMS that can handle this amount of cells as well and they’re quite obscure. In a smaller battery pack I’ve built every individual cell has a current fuse as well as a thermal fuse that pops at 60 deg C.