The lithium battery for your Ford Transit.
The Transit is the most converted van in Britain. It is the base for everything from a weekend Transit Custom day van to a full-size off-grid build, the Ford Nugget factory camper, and a long line of Transit-based coachbuilt motorhomes. Whichever yours is, a drop-in DIN lithium gives you power you can actually live on, kept low in the floor and built to last the life of the van.
The most converted van in Britain
No van gets turned into a camper more often than the Transit, and it comes in two very different sizes. The Transit Custom is the medium van, the default for day vans, weekenders and tidy compact campers, and the base for the Ford Nugget, Ford's own factory camper. The full-size Transit, in its long and high-roof L3 and L4 shapes, is the one people build serious off-grid layouts into. The same van now sits under a growing list of Transit-based coachbuilt motorhomes too, including Bailey's Adamo and Alora, alongside Auto-Trail, Chausson, Roller Team and others.
Because the Transit starts life as a commercial van, most leave the factory with no leisure battery at all, so it gets fitted during the conversion. That is actually an advantage: you get to choose the right battery and where it lives rather than working around what a factory motorhome happened to drop in. A TITAN DIN lithium gives you close to its full rated capacity every cycle, charges far faster than lead-acid, and is built to outlast the van.
Starting from an empty shell? The van conversion guide walks through building around the battery. Upgrading a Transit-based motorhome instead? Start with the motorhome battery guide.
Sizing a Transit conversion
A starting point by build. The Transit spans everything from a compact Custom day van to a full-time L4 build, so size to how you actually use it rather than the badge.
| Build | How it gets used | Good fit |
|---|---|---|
| Transit Custom day van or weekenderLights, fridge, phones, the odd night off hook-up | Modest | 100Ah to 150Ah |
| Transit Custom camper or NuggetHeating, fridge, water, devices, days off-grid | Typical vanlife | 150Ah to 230Ah |
| Full-size Transit conversion (L3, L4)Big build, inverter cooking, longer off-grid | Heavy, sustained | 230Ah to 460Ah |
| Transit-based motorhomeBailey and others - drop-in upgrade from the factory lead-acid | Touring, occasional off-grid | 120Ah to 230Ah |
| Working or welfare vanInverter for tools, charging packs, welfare gear | Bursty, high current | 180Ah to 330Ah |
These are starting points, not fixed rules. The honest figure comes from your loads, not the size of the van, so total them in the battery size calculator. For bigger banks you can run matched packs in parallel or step up to a single larger battery where space allows.
Where the battery fits on a Transit
Because you are usually fitting the leisure battery yourself, you get to pick its home. The flat DIN case suits all three of the common spots:
- Under a cab seat. The tidy choice on a Transit Custom, and where many Transit campervans sit the leisure battery, including Bailey's Ford-based Endeavour and Endurance. It keeps the weight low and central, and our terminals sit low on the case to help clear the seat frame, which can be tight on a swivel base.
- Under a fixed bed or in the rear. Full-size Transit builds usually site larger banks under the rear bed or in a garage, with room to mount the charger and fusing alongside. This is the easiest home for a 230Ah or above.
- In an underfloor locker. Some builds drop a sealed box below the floor, and it is where the Transit-based coachbuilts, such as Bailey's Adamo and Alora, carry their battery. The IP67 case suits this, with one caveat: the RJ45 comms ports sit at IP32 while a cable is plugged in, so keep connected ports clear of standing water.
Wherever it lives, keep it accessible enough to read the terminals and check the connections, keep it off a direct heat source, and measure the space you have, including height for the terminals, before you order.
Charging a Transit
A Transit camper charges from three sources: the engine alternator, roof solar through an MPPT, and mains hook-up. Lithium takes all three happily and charges far faster than lead-acid, so a decent drive or a sunny afternoon puts real capacity back rather than a trickle.
The alternator is the part to get right. Ford has run variable-voltage smart-charge alternators for years, and every Euro 6 Transit does, which means the alternator will not reliably fill a lithium battery on its own. The fix is a DC-DC charger, also called a battery-to-battery charger, and we would fit a Victron Orion every time. It gives the lithium a clean, controlled charge and protects the starter battery. A standard split-charge relay does work, but it is not the most reliable way to charge lithium and some relays cause a backfeed that quietly skims around the top 15% off your usable capacity. Feeding straight off the alternator with no relay and no DC-DC is not something we recommend.
Plan the roof with the solar guide, check your charger against the compatibility list, and size the battery around the gap your charging cannot cover. Every TITAN carries a custom BMS, charges safely down to -30C, and comes with a lifetime, fully transferable warranty.
