Fox ESS
Fox ESS ECS Cube
B4.2 ECS2900
Stackable high-voltage battery modules letting you size storage from ~2.9kWh up to ~16kWh.
2.59kWh
Usable capacity (base)
3.5kW
Power output
15.5kWh
Max with expansion
LFP
Chemistry
10yrs
Warranty
Joint best of 5 we compare
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Our verdict
Modular pricing makes Fox ESS attractive when you want to start small and expand. Pair with a Fox hybrid inverter for the smoothest setup.
Good
- Modular / expandable
- Competitive per-module price
- Widely stocked by UK installers
Watch out
- Needs compatible inverter
- Backup not standard
Specifications
| Usable capacity (base) | 2.59 kWh |
|---|---|
| Power output | 3.5 kW |
| Max with expansion | 15.5 kWh |
| Chemistry | LFP |
| Backup capable | No |
| Warranty | 10 yrs |