How long will a 100Ah lithium battery last in RV?
A 100Ah lithium battery in an RV typically provides 1.2kWh of usable energy (at 12V), lasting 10–36 hours depending on appliance loads. For example, running a 50W fridge (0.5kWh/day) and LED lights (0.15kWh/day) could extend runtime to 2–3 days, while using a 1,000W air conditioner would drain it in ~1 hour. Always factor in a 20% depth-of-discharge buffer to preserve battery lifespan.
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What determines a 100Ah lithium battery’s runtime?
Load power and energy efficiency dictate runtime. A 12V 100Ah LiFePO4 battery stores 1.2kWh, but inverter losses (10–15%) reduce usable energy to ~1kWh. Heavy loads like microwaves (1,200W) drain it in 50 minutes, while LED lighting (10W) lasts 100+ hours.
Runtime calculations require analyzing continuous vs intermittent loads. For instance, a 12V compressor fridge cycling 30% duty (≈40W average) consumes 0.96kWh daily—matching a 100Ah battery’s capacity. Pro Tip: Use energy monitors like Victron BMV-712 to track real-time consumption. Imagine your battery as a water tank: high-pressure appliances (AC units) empty it quickly, while drip-feed devices (phone chargers) sip slowly.
How do RV appliances impact battery life?
High-wattage devices dominate consumption. A 1,500W air conditioner running 2 hours daily needs 3kWh—triple a 100Ah battery’s capacity. Conversely, a 10W vent fan used 12 hours consumes just 0.12kWh.
Prioritize DC-powered appliances over AC ones to avoid inverter losses. For example, a 12V fridge uses 480Wh/day versus 600Wh for a 120V model through an inverter. Practical Example: A weekend trip using lights (0.2kWh), fridge (0.5kWh), and phone charging (0.1kWh) totals 0.8kWh—well within a 100Ah battery’s 0.96kWh safe limit. Pro Tip: Replace resistive heaters with propane systems; a 1,500W space heater drains a 100Ah battery in 40 minutes.
| Appliance | Power (W) | Daily Runtime |
|---|---|---|
| LED Lights | 10 | 10h (0.1kWh) |
| 12V Fridge | 50 | 24h (1.2kWh) |
| Laptop | 60 | 5h (0.3kWh) |
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FAQs
Briefly—most rooftop ACs (1,300–1,500W) drain a 100Ah battery in 40–60 minutes. Use propane or shore power for cooling.
How to extend 100Ah battery runtime?
Optimize loads: Switch to DC appliances, add solar charging (200W+), and avoid inverters for small devices (e.g., USB chargers).