Solar Battery Diesel Heater DC To DC 12V vs Gas Smart Van

LiFePO4 is now the default battery chemistry for van and motorhome builds. The weight and size advantage over AGM is significant, the usable capacity is roughly double for the same rated Ah, and the cycle life is far higher. The question is not whether to use lithium -- it is which size and which model.

These are all Renogy because that is what I have run in my build for two years. They connect directly to the Renogy MPPT, DC-DC charger, and ONE Core monitoring system without any configuration headaches. The pricing below was current at time of writing for both AU and US.

What this guide covers

  1. Why LiFePO4 over AGM
  2. How to size your battery bank
  3. 100Ah options
  4. 200Ah options
  5. 300Ah options
  6. Features worth paying for

Quick picks

Best value
Renogy mini 100Ah LiFePO4 (with free battery monitor) Compact, lightweight, includes a battery monitor. Best entry point for a solo van setup.
Most popular
Renogy 200Ah LiFePO4 with Bluetooth and free battery monitor The most common choice for a full-time build. Enough capacity for a fridge, lighting and charging without running the engine every day.
Cold climate
Renogy 200Ah LiFePO4 with Bluetooth and self-heating Self-heating kicks in before charging when the battery is below 5°C. Essential if you park in sub-zero temperatures.

Why LiFePO4 Over AGM

AGM batteries are cheap upfront but expensive over time. You can only use 50% of an AGM's rated capacity before you damage it, so a 100Ah AGM gives you 50Ah usable. A 100Ah LiFePO4 gives you 80-100Ah usable. For the same effective capacity you need twice the AGM weight and space.

LiFePO4 also handles partial state of charge better, charges faster, and lasts 2,000-5,000 cycles compared to 300-500 for AGM. The upfront cost is higher but the cost per cycle is significantly lower.

FeatureAGM 100AhLiFePO4 100Ah
Usable capacity50Ah (50%)80-100Ah (80-100%)
Cycle life300-5002,000-5,000+
Weight (approx)~28kg~12kg
Charge speedSlow (C/10 typical)Fast (up to 1C)
Upfront costLowerHigher
Cost per cycleHighLow

How to Size Your Battery Bank

A basic rule: work out your daily power draw in Ah, multiply by 1.5, and that is your minimum battery capacity. If you run a 50W fridge 24 hours (100Ah/day) plus lights and charging (20Ah/day), you need at least 180Ah. A 200Ah bank gives you a comfortable buffer.

For a weekend van, 100Ah is usually enough. For full-time living with a fridge, hot water, and regular device charging, 200Ah is the practical minimum. If you are in overcast climates or running a diesel heater controller, 300Ah gives you security.

Two batteries or one? Two 100Ah batteries wired in parallel give the same capacity as one 200Ah and cost a similar amount. The advantage of two is redundancy -- if one fails, you still have power. The 200Ah single battery is simpler and lighter.

100Ah Options

Renogy mini 100Ah 12V LiFePO4 (includes free battery monitor)

100Ah BMS included Free monitor 11.9kg

The mini series is smaller and lighter than the standard Renogy range. Comes with a free battery monitor, which alone is worth $50-70 separately. Good choice for a first build or a secondary battery.

Renogy 100Ah 12V LiFePO4 with Bluetooth

100Ah Bluetooth BMS included

Standard Renogy form factor with Bluetooth built in. Monitor state of charge from your phone via the DC Home app without a separate battery monitor. Compatible with the Renogy ONE Core display.

Renogy 100Ah 12V LiFePO4 with Bluetooth and Self-Heating

100Ah Bluetooth Self-heating

Self-heating protects the battery in temperatures below 5°C. Without it, charging a lithium battery below freezing can permanently damage the cells. If you travel in winter or park overnight in cold climates, this feature is worth the premium.

200Ah Options

Renogy mini 200Ah 12V LiFePO4 (includes free battery monitor)

200Ah Free monitor Compact

The mini form factor in 200Ah. Lighter and smaller than the standard 200Ah, which matters in a van where space under the bed is tight. Includes a free battery monitor.

Renogy 200Ah 12V LiFePO4 with Bluetooth and Free Battery Monitor

200Ah Bluetooth Free monitor

The most popular choice for a full-time van or motorhome build. Bluetooth monitoring, a free battery monitor included, and enough capacity to run a fridge, lights, and daily charging without daily engine running.

Renogy 200Ah 12V LiFePO4 with Bluetooth, Self-Heating and Free Battery Monitor

200Ah Bluetooth Self-heating Free monitor

Everything in one: 200Ah capacity, Bluetooth, self-heating for cold climates, and a free battery monitor. The best all-round option if you travel year-round and want to cover all bases.

300Ah Options

Renogy mini 300Ah 12V LiFePO4 (includes free battery monitor)

300Ah Free monitor Compact

300Ah in the compact mini form factor. Right for a larger motorhome setup, a two-person full-time build, or anyone running high loads like an air conditioner or large inverter regularly.

Renogy 300Ah 12V LiFePO4 with Self-Heating and Free Display

300Ah Self-heating Free display

The top-end Renogy option. Self-heating, a free battery display, and 300Ah of capacity. Built for serious off-grid use where you might be stationary for days without solar input.

Features Worth Paying For

Bluetooth: Lets you see state of charge, voltage, current, and temperature from your phone. Pairs with the Renogy DC Home app and the ONE Core display. Worth having on at least one battery in your bank.

Self-heating: Prevents charging damage below 5°C. Not needed if you never park overnight in cold weather. Essential if you do.

Built-in BMS: All the Renogy batteries listed here include a battery management system that handles overcharge, over-discharge, short circuit, and temperature protection. Do not buy a bare cell without one.

Dual battery kits: If you want two batteries wired as a bank, Renogy sells matched pairs with cables included.

Renogy Dual Battery Kits — AU + US

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