Skip the math? For most couples boondocking in a travel trailer, one Eco-Worthy 12V 280Ah metal-case LiFePO4 battery covers 2–3 days of real use without recharging — and we sell it with free U.S. shipping & free 30-day returns, priced below every major retailer we checked. 10% off your entire order with code RVSAFE10.
"How many amp-hours do I need?" is the most common question in RV power upgrades, and the honest answer is: it depends on what you run and how long you camp between hookups. Here's how to size it properly in ten minutes.
Step 1: Add up your daily loads
Work in watt-hours (Wh) — it keeps 12V appliances and inverter loads in the same units. Typical daily figures for a couple in a travel trailer:
| 12V compressor fridge | 600–900 Wh/day |
| Lights (LED, evening use) | 50–100 Wh/day |
| Water pump | 30–60 Wh/day |
| Phone/laptop charging | 100–200 Wh/day |
| Vent fans (MaxxAir-style, evening + night) | 150–300 Wh/day |
| Furnace blower (cold nights) | 300–600 Wh/day |
| TV / router / misc inverter loads | 200–400 Wh/day |
Typical total: 1,400–2,500 Wh per day. Coffee makers, microwaves, and hair dryers add bursts; air conditioning is its own project entirely.
Step 2: Convert battery sizes to usable energy
LiFePO4 batteries can be discharged 80–100% without damage — unlike lead-acid, which should stop at 50%. At 12.8V nominal:
- 100Ah = 1,280 Wh — about half a day to one light day
- 200Ah = 2,560 Wh — about one full day
- 280Ah = 3,584 Wh — about a day and a half to two-plus days, or 2–3 days with modest solar
Step 3: Match the battery to how you camp
- Weekend hookup camper: a single 100Ah lithium is genuinely enough — don't overspend. The battery mostly bridges travel days.
- Occasional boondocker (1–2 nights): 200Ah class, or 280Ah if you run a furnace or CPAP at night.
- Regular boondocker / off-grid weeks: 280Ah minimum, paired with 200–400W of solar. This is where the Eco-Worthy 280Ah hits the sweet spot: one battery, one cable run, 3,584Wh, and a 200A BMS that supports a 2,000W inverter.
- Big inverter household loads (3,000W+): two batteries in parallel — you need the combined BMS current headroom, not just the capacity.
Why one big battery beats several small ones
Two 100Ah batteries cost more than one 280Ah in almost every brand lineup, take double the compartment footprint, and add interconnect cables that need to be sized and torqued correctly. One high-capacity pack is simpler, cheaper per watt-hour, and — in the Eco-Worthy's case — arrives in a metal enclosure with mounting feet and a one-touch output disconnect switch, so it installs directly without a battery box. Weight is the one trade-off: at 68.5 lb it's a two-person lift into a tongue box.
Don't forget the charging side
A bigger battery only helps if you can refill it. Check that your converter has a lithium (14.4–14.6V) charge profile, and consider solar sized at roughly 10–15% of your battery's Wh rating in panel watts — 300–500W of panels for a 280Ah pack. See our install and charging guide for the full setup.
Bottom line
Size from your loads, not from forum bravado: 100Ah for hookup campers, 200Ah for occasional boondockers, 280Ah for everyone who camps away from pedestals regularly. Comparing brands at the 280Ah level? Read our Eco-Worthy vs LiTime vs Renogy vs Battle Born comparison — then check the live price on our 280Ah product page.