Stealth Energy Stealth 550 Battery

Stealth Energy Stealth 550 Battery is a 12V automotive battery built for serious car audio installs, delivering 55.0Ah nominal capacity and a 660A max discharge in an ABS enclosure with a T6 terminal.

• Nominal Voltage: 12V — standard for automotive electrical systems, ensuring compatibility with typical amplifiers and electronics.
• Nominal Capacity (20HR) and Rated Capacity: 55.0AH (nominal); RATED CAPACITY includes 57.2 AH/2.86A (20hr), 55.0 AH/5.50A (10hr), 47.3 AH/9.46A (5hr), 42.9 AH/14.3A (3hr), 33.6 AH/33.6A (1hr) — shows how capacity changes with discharge rate in real-world loads.
• Max Discharge Current: 660A (5s) — enables high-current bursts for amplifiers without excessive voltage sag.
• Internal Resistance: approx 7.5mΩ — lower resistance reduces voltage drop during peaks, helping maintain system voltage under load.
• Dimensions: Length 229+3 mm (9.02 in); Width 138+2 mm (5.43 in); Container Height 205+3 mm (8.07 in); Total Height with Terminal 211+3 mm (8.31 in).
• Container Material: ABS — rigid enclosure designed to withstand vehicle environments.
• Terminal: T6 — terminal type specified for connection compatibility.
• Operating Temperature & Capacity Variation: Discharge range -15 to 50 C; Charge 0 to 40 C; Storage -15 to 40 C. Capacity varies with temperature: 40 C 103%, 25 C 100%, 0 C 86%.
• Cycle and Standby/Charging Guidance: Cycle Use—initial charging current < 15.5A; voltage 14.4–15.0V at 25 C; temp coefficient -30mV/°C. Standby Use—no initial-current limit; voltage 13.5–13.8V; temp coefficient -20mV/°C.
• Self-Discharge: Can be stored up to 6 months at 25 C; higher temperatures shorten the interval and a freshening charge is required.

In a high-current car audio build, this battery provides a robust energy reserve with predictable performance across a range of loads and temperatures. Its high peak capability, documented charging parameters, and durable ABS enclosure make it a reliable choice for multi-amp systems, front-stage kilowatt setups, and bass-heavy installs where voltage stability is essential.