Runtime calculator
12V 100Ah LiFePO4 Battery Runtime Calculator for RV, Marine & Solar
Runtime is best treated as a planning estimate, not a fixed promise. Start with 1280Wh for one ReliableVolt ZM12100 battery, multiply by realistic system efficiency, then divide by the device watts.
Runtime formula
Use this formula: runtime hours = battery watt-hours x efficiency / device watts. For one ZM12100, the planning value is 1280Wh. Two batteries can be estimated as 2560Wh, and four batteries as 5120Wh when the system design supports that pack arrangement.
Common load presets
Typical planning loads include RV Fridge 80W, CPAP 40W, Trolling Motor 300W, LED 30W and Router 50W. A 40W CPAP load estimates much longer runtime than a 300W motor load because watts drive the calculation.
Why real runtime changes
Inverters, motor speed, compressor cycling, wiring, temperature, age and charger behavior change real-world results. Trolling motors and pumps are especially variable because load changes with conditions.
Pack planning
Choose 1-Pack for single 12V RV or backup loads, 2-Pack for compatible 24V trolling motor planning or expanded 12V capacity, and 4-Pack for compatible 48V solar bank planning. Confirm wiring documentation before building series or parallel systems.
Shipping reminder
Battery orders are handled under Ground Shipping Only, Contiguous U.S. Only, No PO Boxes / APO / FPO / DPO / AK / HI, with a lithium ground-shipping check required.
Quick FAQ
How do I estimate runtime for a 12V 100Ah LiFePO4 battery?
Use battery Wh x efficiency divided by device watts. For ZM12100, start with 1280Wh and treat the result as a planning estimate.
Which pack should I choose for longer runtime?
A 2-Pack or 4-Pack can increase planning energy when the system design supports that arrangement, but wiring and charger compatibility must be confirmed.