The store of energy for your system. Several batteries wired together act as one larger bank; LiFePO₄ is the common chemistry for off-grid because it is light, long-lived and safe.
The battery bank is the heart of an off-grid system — it stores the energy your panels and alternator make so you can use it after dark or at anchor. Get its size wrong and you either run out at 2am or pay for capacity you never use.
It sits at the centre of the system: charge sources feed into it, loads draw from it, and a main fuse and switch guard the connection. Several batteries wired together behave as one larger bank.
Design your van, boat, cabin or RV system in Wattonomy and it sizes the bank to your real daily energy and days of backup — including the cold-weather capacity hit — and shows the exact Ah and chemistry on the diagram — from the appliances you actually run, sized to the recognized standard for your region. You see it on the wiring diagram, in the sized parts list, and in a plain-English build pack that explains the reasoning behind every choice. No account, no email — about a minute to a complete, validated design.
It depends on your daily watt-hours and how many days of backup you want. Add up your real loads, allow for an honest depth of discharge and cold-weather losses — or let Wattonomy size it from your appliances in about a minute.
Avoid it. Different ages and capacities fight each other in a bank; the weakest drags the rest down. Build a bank from matched batteries of the same age, type and capacity.
It takes about a minute. No account, no email.