Fox ESS CQ7 7.02kWh Master Battery V3+

Note on connecting to inverters: Currently the cables and crimps that come with these batteries don't fit the Y cable. You can use the current cable, but if you are installing just one stack there will be a branch coming off that isn't connected to anything.

These V3+ batteries use a special firmware meaning a minimum of 3 batteries (1 primary and 2 secondaries) is always needed.

Fox's CQ7 is a high voltage 7.02kWh stackable battery system, composed of one master battery and CQ7 Slave Batteries.  Up to 14 modules can be stacked, connecting the modules in series and providing up to 98.28kWh of storage, this modular design allows for significant flexibility in storage applications. Installation is simple, featuring a plug and play solution that saves valuable time for installers.

High Performance

The CQ7s achieved a record breaking 97.0% System Performance Index (SPI) in the Hochschule für Technik und Wirtschaft Berlin Energy Storage Inspection in 2026. They can operate in a large temperature range, with the warming function on battery charging and discharging can occur at temperatures as low as -25°C.

Modular Design and Flexibility

Up to 7 CQ7 modules can be stacked in in single phase installations offering a storage capacity of up to 49.14kWh. For three phase installations this capacity is doubled to 98.28kWh with up to 14 modules in a stack. A minimum of 3 modules (1 master and 2 slaves) must be used for single phase and three phase systems. This flexibility in storage capacity allows installers to build storage around the needs of each project.