Building a hybrid battery is not just assembly work. It is cell grading, matching, welding, BMS integration and functional testing, run to the same standard whether we are building three packs for a workshop or three hundred for a distributor.
Cell and module grading
Everything starts with sorting. Cells and modules arriving from our suppliers are logged, capacity-tested and grouped by generation, measured capacity and internal resistance. A pack is built from a matched set, because it is only as strong as the spread across its blocks.
- Every module capacity-tested and resistance-measured on intake
- Grouped by generation, capacity band and resistance band
- Cells outside tolerance rejected and returned to the supplier — never entering a pack
- Full intake record kept against the pack serial number
Pack assembly
Mechanical build
Busbar and nickel strip preparation, torque-controlled assembly, and a new enclosure with new gaskets and hardware on every pack.
BMS integration
New BMS board fitted, balance circuit verification, and a live communication check with the vehicle-side harness before the lid goes on.
Thermal and sealing
Fan and duct service, thermal interface renewal, then a sealing and insulation check on the finished enclosure.
Key process stations
Cell matching & insulation
Voltage, resistance and capacity spread verified against the build sheet before a module is accepted into a pack.
Welding & interconnect
Controlled welding with pull-test sampling, so a joint is proven rather than assumed.
BMS test bench
Functional and communication verification on a rig that simulates the vehicle before the pack is closed.
Charge & discharge cycling
Forming cycles and capacity confirmation, logged per serial number.
Ageing & re-test
Held at temperature, rested, then tested again so drift happens here rather than in the customer’s car.
Label, trace & pack-out
Serial labelling, test sheet matched to the unit, and crate packing to the shipping specification.
Quality and consistency
The usual failure in this industry is not a bad design, it is a good build done inconsistently. We lock the process instead of relying on whoever is on the bench that day.
- Written work instructions covering every critical step and torque value
- Inspection points at each station, with results recorded against the serial number
- Periodic re-verification of finished stock so a batch behaves the same months later
- Non-conforming units quarantined on the spot, not reworked quietly
From sample to volume
- Engineering sample – one or a few packs built to your specification so you can fit and test it yourself.
- Process review – we agree the build sheet, test limits and documentation set based on what your market requires.
- Pilot run – a small batch through the full line to lock the process and confirm repeatability.
- Volume and repeat orders – controlled batch consistency, the same serial-level records, and capacity held for standing orders.