48V MILD HYBRID BATTERIES

What Does the 48V Mild Hybrid Battery Do?

Mild hybrids (MHEVs) run a second electrical system on top of the standard 12V, usually 48V, to recover and reuse energy without ever plugging in.

At the centre of it is a belt-driven or integrated starter-generator, branded differently depending on the manufacturer (BSG, ISG, eTorque, EQ Boost, among others). Under braking or coasting, it switches to generator mode and captures energy that would otherwise be lost as heat, storing it in the 48V battery. Accelerate, and that energy comes back out: smoother, quieter engine restarts after stop-start, plus a small torque boost.

Because the 48V system usually sits below the 60V threshold that triggers stricter high-voltage rules, these batteries can generally be worked on without full HV certification, though you should still disconnect both the 12V and 48V systems safely before touching anything.

Below: new, used and refurbished OEM 48V mild hybrid batteries and individual modules, tested and warrantied, matched to your make and model.

Signs of a Failing 48V Mild Hybrid Battery

• Rougher, slower engine restarts instead of the usual smooth stop-start
• Fuel economy creeping up, since the mild hybrid system isn’t pulling its weight
• Mild hybrid or “eco” warning light on
• Fault codes pointing to the starter-generator (BSG/ISG)
• Start-stop switching itself off or refusing to engage at all

New, Used & Refurbished OEM Units & Modules

Available as complete batteries or individual modules, in new, used or refurbished condition depending on your model. All units are capacity- and health-tested before shipping, with a 12-month warranty.

Compatible Makes & Models

Filter by make below, or search by part number.

Testing, Warranty & Exchange Service

Every 48V battery or module is tested for capacity and health before it leaves us, backed by a 12-month warranty. Exchange parts require a refundable deposit, returned once we get your old unit back.

Frequently Asked Questions

Do I need to plug in a mild hybrid to charge the 48V battery?

No, it charges entirely through regenerative braking and the starter-generator while you drive. Mild hybrids don’t have a charging port for this.

What’s the actual difference between a mild hybrid and a full hybrid?

A mild hybrid assists the engine with smoother restarts, a torque boost, and energy recovery, but it can’t drive on electric power alone. A full hybrid can, at least for short stretches.

Is it dangerous to work on a 48V system?

It sits below the voltage that requires specialist HV certification, but you should still disconnect it properly before any work, following the manufacturer’s procedure.