Why Battery Swapping May Actually Need Fewer Packs, Not More

Battery swapping has long carried a reputation problem: the assumption that every swap station must stockpile dozens of spare packs, driving up cost and resource use. A fresh look at how the model works in practice — prompted by an interview with Janus Electric CEO Ben Hutt — suggests that intuition may be backwards.

Janus Electric, an Australian company, converts diesel semi trucks into electric drivetrains and pairs them with a battery swap system. The interviewer’s question was a natural one: how much extra battery capacity does a swap operation really require? The answer, as Hutt framed it, is less than a one-to-one ratio would imply, because packs are shared across a fleet rather than parked inside individual vehicles.

The logic rests on utilization. A truck that sits idle while charging ties up a battery doing nothing. In a swap model, the same pack can serve multiple vehicles over a day, cycling through charge and discharge far more often. That higher turnover means fewer packs are needed to keep the same number of trucks moving — a point that rarely surfaces in debates over swapping’s material footprint.

For heavy-duty fleets, the implications reach beyond pack count. Swapping can shrink downtime at depots, reduce the peak charging load a site needs to support, and let operators buy energy when it is cheapest. It also shifts the battery from a fixed asset inside each truck to a shared resource managed at the fleet level.

The takeaway is not that swapping wins everywhere. Passenger EVs, with their varied routes and long dwell times at home, remain a different case. But for high-utilization commercial vehicles in Australia and elsewhere, the arithmetic looks more favorable than the usual skepticism suggests — fewer batteries, worked harder, may outperform more batteries sitting still.