Battery technology has changed dramatically in the last few years, and honestly, most of the advice you'll find online is already outdated. If you're reading forum posts or watching YouTube videos from even 2-3 years ago, the battery recommendations are going to steer you wrong.
Get LiFePO4 (lithium iron phosphate) batteries from a reputable budget brand like Eco-Worthy. There's no good reason to choose anything else anymore.
Prices have dropped enough that we recommend 280Ah even if you think you'll need less — the cost difference from a smaller battery is minimal, and the extra buffer for cloudy weather and future devices is worth a lot of peace of mind.
A few years ago, LiFePO4 batteries cost $800-1,200 per 100Ah — 4x the price of AGM. That made it a real debate. Not anymore.
LiFePO4 now costs about the same as AGM — and gives you nearly 2x the usable capacity.
Chinese manufacturers flooded the market with quality LiFePO4 batteries using the same EVE and CATL cells as premium brands. A 280Ah LiFePO4 battery now costs $330-400 — the math is overwhelmingly in favor of lithium.
There are several lithium chemistries. Here's why LiFePO4 (lithium iron phosphate) is the right choice for vans:
Okay, you're convinced on LiFePO4. How much capacity do you actually need? For most people, the answer is 280Ah — and the reason is simple: the cost bump from a smaller battery isn't that big, but the extra buffer is worth a lot of peace of mind.
A 200Ah battery costs $350-500. A 280Ah battery costs $330-400. That's roughly $50-100 more for 40% more capacity. The extra headroom means you can weather cloudy days without stressing, add devices later without upgrading your battery, and generally not think about power management as much.
Even if you're only doing weekend trips now, your usage tends to grow — you add a fridge, start taking longer trips, maybe work from the van occasionally. Starting with 280Ah means you won't outgrow your battery as quickly.
Your solar might only generate 800Wh per day in winter. If you're consuming 1,500Wh per day, you're running a 700Wh deficit.
That extra day or two of buffer means you can wait out a storm or a stretch of cloudy days without stressing about your battery level.
Your power needs tend to grow over time. A fridge adds ~400Wh/day, Starlink adds ~250Wh/day, a diesel heater adds ~150Wh/day. With 280Ah, you have room to add devices without immediately needing to upgrade your battery.
280Ah batteries come as a single unit — installation is the same as a 200Ah battery. Same physical mounting, same wiring complexity. Only ~20 lbs heavier (~70 lbs vs ~50 lbs).
Absolutely. Some people run 400Ah, 600Ah, or even more. This makes sense if:
But for most people, starting with one 280Ah battery makes more sense than buying two upfront. It's simpler, lighter, and cheaper — and you may find it's all you need.
That said, it's smart to design your layout with space and wiring for a second battery, so you can add one later if you need it. Adding a battery in parallel is straightforward, but only if you've left room for it.
One 280Ah 12V battery vs. two 140Ah 12V batteries in parallel vs. 24V systems - this gets into the weeds, but here's the simple answer:
Why:
24V systems make sense if you're running very high-power inverters (5000W+) or very large battery banks (800Ah+), but that's not most people. A 3000W inverter works perfectly fine on 12V. Stick with 12V and keep it simple.
Parallel batteries (connecting multiple 12V batteries together) can work fine, but now you have more connection points, batteries that can drift out of balance, and more complex installation. If you need more than 300Ah, sure, run two batteries in parallel. But if 280Ah will work, just get one battery and keep your life simple.
"Should I spend $1,200 on a Battle Born battery instead of $400 on an Eco-Worthy?" Here's the reality: budget brands use the same or similar cells, just without the markup.
Worth it for $100k+ professional builds. Overkill for DIY.
The sweet spot for DIY van builds.
When shopping for your 280Ah LiFePO4 battery, look for:
LiFePO4 batteries are pretty simple to install, but a few tips:
These batteries are heavy (70 lbs). Use proper mounting brackets or a battery box. You don't want it sliding around or tipping over.
LiFePO4 batteries don't off-gas like lead-acid, but they still can generate some heat. Don't seal them in an unventilated box.
Put a fuse or circuit breaker on the positive terminal. Size it for your max expected draw (maybe 200A for most systems). This is critical for safety.
Use thick wire (probably 2AWG or bigger) for the main battery connections. Don't cheap out here.
Install a battery monitor (like a Victron SmartShunt, $150) so you can track exactly how much power is going in and out. Bluetooth monitoring built into the battery is good, but a separate shunt is better.
Don't bury your battery under your bed platform. You might need to access it for troubleshooting or to disconnect it.
Get an Eco-Worthy 280Ah LiFePO4 battery (~$400). It has Bluetooth monitoring, a built-in BMS, and uses the same cells as batteries costing 3-4x more.
Skip Battle Born and other premium brands unless you're building a $100k+ professional van. For a DIY build, save the $500-800 and spend it on solar panels or just... camping.
This will give you 3,584Wh of capacity that will last 10+ years. Five years ago, this same capacity would have cost $3,000-4,000 and weighed three times as much.