What is a camper house battery?
A camper house battery is a deep-cycle energy storage system designed to power RV appliances and electronics off-grid. These 12V/24V/48V batteries use lead-acid, AGM, or lithium-ion (LiFePO4) chemistries, providing sustained power for lighting, fridges, and HVAC systems. Lithium variants dominate modern RVs due to 80%+ depth of discharge, 3,000–5,000 cycle lifespans, and 50–70% weight savings versus traditional options. Top-Rated RV Batteries for Reliable Power
What distinguishes deep-cycle from starter batteries?
Deep-cycle batteries prioritize longevity over cranking amps, using thicker plates (3–6 mm vs. 1–2 mm) for sustained 20–100A discharges. Unlike starter batteries that deliver 300–800A bursts, they withstand 50–80% daily depletion without premature failure. Pro Tip: Never substitute car batteries for house loads—shallow cycling destroys starter units in weeks.
Structurally, deep-cycle lead-acid models feature tubular or flat plate designs with high-density active material. Lithium variants like LiFePO4 achieve 10x faster recharge rates (0.5–1C vs. 0.1C for AGM). For example, a 200Ah lithium battery can power a 12V RV fridge for 4–5 days vs. 1.5 days with AGM. But what happens if you mix chemistries? Parallel connections risk thermal runaway due to voltage mismatches. Always use identical batteries in banks.
How to calculate required battery capacity?
Multiply appliance wattage by runtime hours, then divide by system voltage. Add 20% buffer for inefficiencies. For lithium, usable capacity = rated Ah × 0.8 (DoD).
Start by listing all loads: LED lights (10W × 5h = 50Wh), 12V fridge (60W × 24h = 1,440Wh), inverter TV (100W × 3h = 300Wh). Total 1,790Wh ÷ 12V = 149Ah. With lithium’s 80% DoD, 149 ÷ 0.8 = 186Ah minimum. Practically speaking, most mid-size RVs use 200–300Ah banks. Pro Tip: Prioritize LiFePO4 if weight matters—100Ah lithium weighs 30 lbs vs. 60 lbs for AGM.
| Battery Type | Cost per kWh | Cycle Life |
|---|---|---|
| Flooded Lead-Acid | $150 | 400–600 |
| AGM | $250 | 600–1,200 |
| LiFePO4 | $600 | 3,000–5,000 |
Why choose lithium over AGM for RVs?
Lithium batteries offer 3x lifespan, twice the usable capacity, and 50% faster charging versus AGM. They maintain voltage stability under load, preventing appliance brownouts.
While AGM struggles beyond 50% discharge, LiFePO4 handles 80–100% DoD daily. A 100Ah lithium delivers 80Ah vs. AGM’s 40Ah. Charging-wise, lithium accepts 50–100A current (0.5–1C rate), refilling in 1–2 hours via solar. AGM limits to 20–30A (0.2C), needing 5+ hours. But are there downsides? Upfront cost—$900 vs. $300 for AGM—but TCO favors lithium after 500 cycles. For cold climates, lithium self-heating models add $200 but enable -20°C operation.
How to maintain camper batteries in winter?
Store lithium at 50% SoC in 10–25°C environments. For lead-acid, keep fully charged to prevent sulfation. Disconnect parasitic loads draining >0.5% daily.
Lithium’s low self-discharge (2–3% monthly) suits seasonal storage. Lead-acid needs monthly top-ups—a 100Ah AGM loses 5–10% per month. In subzero temps, use battery warmers maintaining ≥5°C. Pro Tip: Install a disconnect switch to eliminate phantom loads like LP gas detectors. For example, a 0.3A parasitic draw drains 7.2Ah daily—enough to kill an AGM bank in 3 weeks.
| Maintenance Task | Lead-Acid | Lithium |
|---|---|---|
| Water Refills | Monthly | Never |
| Voltage Checks | Weekly | Quarterly |
| Equalization | Every 3 months | Not Required |
Fasta Power Expert Insight
FAQs
No—starter batteries lack deep-cycle construction. Repeated 50% discharges degrade them within weeks.
How long do lithium camper batteries last?
8–15 years with proper care, versus 3–5 years for AGM. Avoid temperatures above 45°C for longevity.
Do lithium batteries need ventilation?
Unlike lead-acid, LiFePO4 doesn’t off-gas, allowing sealed compartment installations. Maintain 10cm clearance for heat dissipation.
What size inverter works with 200Ah lithium?
Match inverter wattage to load peaks. A 200Ah 12V bank (2,400Wh) pairs with 2,000W pure sine inverters for 80% safe draw (1,600W).
Best Deep Cycle Battery for RVs