More than most people specify, and it usually matters more than the battery choice. TMR’s MRTS213 requires an IP-rated double-skinned enclosure with ventilation slots, thermostatically controlled fans and a heater, white (N14) heat-reflective paint to AS 2700, and an internal temperature held between 0 °C and 50 °C, with batteries low, controller above and switchboard at top. Main Roads WA requires internal temperature within ±10 °C of outside ambient within a 10–60 °C range, thermostat regulated. The 0 °C minimum with a heater is not incidental: it exists because LiFePOâ‚„ must not be charged below freezing, and both TMR and NZTA have engineered around that explicitly.