Glossary Term
Battery Bank
A battery bank is two or more batteries connected together to provide a required voltage, a required capacity, or both. In yacht use, the term usually refers to a grouped DC power source assigned to a function such as engine starting, hotel loads, emergency services, thrusters, or energy storage support. ABYC defines a battery bank as batteries connected in series for higher voltage or in parallel for increased capacity.
Within a superyacht electrical system, the battery bank is defined less by the chemistry than by the job it performs and the way it is protected. A start bank is built for high current over short periods. A service or house bank is sized for sustained onboard loads. In hybrid and battery-supported yachts, larger banks may also sit inside a wider storage architecture with chargers, converters, monitoring, and protection coordinated through the electrical and electronic system.
Battery-bank work draws technical attention when owners add hotel loads, replace lead-acid with lithium systems, extend silent operation, or chase recurring discharge problems. Cable sizing, fusing, isolation, charging logic, ventilation, fault current, and location all affect whether the bank remains safe and serviceable. A battery bank that looks adequate by amp-hours alone can still be wrong for the yacht if the charge regime, protection concept, or duty profile does not match the loads it is expected to carry.