Ford Transit Custom Dual Battery System — Complete Guide for Tradies & Tourers

If you're running tools, lighting, a fridge, or accessories in your Ford Transit Custom, a reliable dual-battery system is essential. Whether you’re a tradie powering cordless tool chargers or a weekend explorer running a fridge and lighting, having a dedicated lithium setup ensures your gear stays powered — without draining your vehicle battery.

In this guide, we’ll break down the best way to power your Transit Custom, what to look for in a dual battery system, and why an under-seat 100Ah PowerDeck™ is the smartest solution.

Why the Transit Custom Needs a Dual Battery System

The Transit Custom is a popular platform for:

Electricians & sparkies
HVAC + service techs
Plumbers, carpenters & builders
Mobile mechanics
Fleet & government vehicles
Weekend campers & adventure vans

But running power tools, inverters, fridges and work lighting from your starter battery is risky — one dead battery can stop your entire day or leave you stranded.

A dual-battery system isolates power draw, protecting your starter battery and ensuring your vehicle always starts.

Why Lithium Wins for Trade Vans

Lithium (LiFePO₄) benefits:

High usable capacity
Fast charging from alternator
Lightweight vs AGM
Compact footprint
Long cycle life — ideal for daily use

A 100Ah lithium battery typically replaces a bulky 150–200Ah AGM system — just with better performance and less weight.

Best Transit Custom Dual Battery Location: Under the Seat

The smartest install location on the Transit Custom is:

Under the passenger seat

Why?

No cargo space lost
Hidden, factory-style install
Shorter cable runs = better efficiency
Protected from load space impact, dust and cargo

This is where PowerDeck™ 100Ah is designed to live — a clean, OEM-fit power hub.

The Complete Power Solution — PowerDeck™ 100Ah

Our PowerDeck™ 100Ah for Transit Custom includes:

100Ah LiFePO₄ battery
Smart onboard DC-DC charger
Pure sine inverter (2,000W)
Fuse protection + wiring kit
Anderson input/output ports
Digital volt display + USB outlets
Plug-and-play ignition sense wire

It’s engineered for professional daily use. Plug it in, charge while driving, and power your tools or fridge anywhere.

Who the 100Ah System Suits

Choose 100Ah if you:

Use daily trade tools + chargers
Run a fridge & lights
Want fast charging + light weight
Need a compact system with zero cargo loss

Perfect for mobile trades and touring rigs.

Need more runtime for extended off-grid?
A 200Ah model is also available.

Transit Custom Dual Battery Install Tips

General setup guidelines:

Secure the battery under passenger seat
Use heavy-gauge wiring and proper fusing
Use ignition-triggered charging to protect starter battery
Test charging voltage and inverter output
Allow airflow around electronics

Prefer plug-and-play? The PowerDeck™ installs cleanly with no messy wiring in the cargo bay.

What Else Can You Power?

With a 100Ah lithium power hub you can run:

Tool chargers
LED work lights
Fridge/freezer
Laptop & device charging
Air compressor
Small power tools
240V appliances via inverter

Final Thoughts

The Ford Transit Custom is built to work — and with the right dual-battery system, you can work anywhere. A compact under-seat 100Ah lithium system gives you real power without sacrificing space, and helps keep your business running efficiently every day.

Get the full specs and order your Transit Custom PowerDeck™ here:
CLICK HERE

Ford Transit Custom Dual Battery Guide: Best 100Ah Lithium Under-Seat System for Trade Vans