Fox ESS EQ5000 4.92kWh Slave Battery – EQ5000-S

Expand a compatible Fox ESS high-voltage storage system with the Fox ESS EQ5000 4.92kWh Slave Battery. The EQ5000-S uses safe lithium iron phosphate (LiFePO₄) chemistry in a compact, heated and modular floor-standing design.

The EQ5000-S Slave provides 4.92kWh nominal capacity and can be used in two distinct ways: as an additional module in a conventional EQ5000 stack controlled by an EQ5000-M Master, or directly beneath a compatible Fox ESS PowerQube / PQ1 all-in-one inverter.

Important: The EQ5000-S cannot operate independently. A conventional EQ5000 system requires 1x EQ5000-M Master plus at least 1x Slave. A PowerQ / PQ1 system instead requires 2-6 EQ5000-S Slave batteries and does not use the separate Master.

Compatibility: EQ5000 system size depends on the connected Fox ESS inverter. Always check the exact inverter model, firmware and current Fox ESS compatibility guidance before ordering.

Included in Kit

• 1x Fox ESS EQ5000 4.92kWh Slave Battery

Not included: For a conventional EQ5000 installation, the controller / BMS is contained within the separately purchased EQ5000-M Master battery. For a PowerQ / PQ1 installation, the compatible all-in-one inverter provides the required system control.

Building a conventional EQ5000 stack? Add the Fox ESS EQ5000 4.92kWh Master Battery HERE.

Building a PowerQ system? View the forthcoming Fox ESS PowerQ / PQ1 listing HERE.

Fox ESS EQ5000 Battery Sizing and Scalability

The minimum and maximum number of EQ5000 batteries varies by inverter. The current Fox ESS sizing guidance shows:

Conventional EQ5000 systems: Every stack contains 1x EQ5000-M Master, with EQ5000-S Slave batteries added to reach the required system size. The smallest conventional stack contains 1x Master and 1x Slave, providing 9.84kWh nominal capacity.

H3 Pro: Fox ESS lists support for 2-12 EQ5000 batteries. Because each series stack is limited to six modules, systems above six batteries use the supported multi-stack arrangement and require one Master per stack. Confirm the final design against the exact inverter model and current Fox ESS guidance.

PowerQ / PQ1 systems: The all-in-one inverter replaces the separate battery controller. Its battery section is therefore built from 2-6 EQ5000-S Slave modules only, providing 9.84-29.52kWh nominal storage.

Key Features of the Fox ESS EQ5000 Slave Battery

• 4.92kWh nominal capacity per battery module
• Dual application for conventional EQ5000 Master-led stacks or compatible PowerQ / PQ1 all-in-one systems
• High-voltage LiFePO₄ chemistry for a safe and durable storage solution
• 90% Depth of Discharge, providing approximately 4.43kWh usable capacity per module
• Scalable modular design with up to six modules connected in series
• More than 95% battery pack round-trip efficiency under stated test conditions
• 50A maximum continuous charge / discharge current
• 65A peak discharge current for 60 seconds
• IP65 rated for indoor or outdoor floor-standing installation
• Integrated battery heating for improved cold-weather operation
• Natural convection cooling with no cooling fan required
• CAN-based system communication
• 12-year manufacturer warranty, subject to registration and current Fox ESS terms

Capacity and Electrical Specifications

• Nominal Capacity: 4.92kWh per module
• Approximate Usable Capacity: 4.43kWh per module at 90% DoD
• PowerQ / PQ1 Capacity Range: 9.84-29.52kWh nominal using 2-6 Slave modules
• Nominal Voltage: 64V per module
• Recommended Discharge Current: 38.5A
• Maximum Continuous Charge / Discharge Current: 50A
• Peak Discharge Current: 65A for 60 seconds
• Battery Pack Round-Trip Efficiency: More than 95%
• Depth of Discharge: 90%
• Cycle Life: At least 6,000 cycles under the manufacturer’s stated test conditions
• Communication: CAN-based system communication

Physical Specifications

• Slave Module Dimensions (W x H x D): 570 x 170 x 380mm
• Slave Module Weight: Approximately 41kg
• Minimum Conventional Two-Module System Dimensions (W x H x D): 570 x 375 x 380mm
• Minimum Conventional Two-Module System Weight: Approximately 97.2kg including the assembled system components
• Installation: Indoor or outdoor, floor-standing
• Ingress Protection: IP65
• Cooling: Natural convection

Operating Conditions

• Standard Charging Temperature: 0°C to 55°C
• Standard Discharging Temperature: -10°C to 55°C
• With Battery Warming Function: Operation down to -25°C, subject to system conditions
• Storage Temperature: -10°C to 50°C
• Humidity: 5-95%, non-condensing
• Maximum Altitude: 3,000m

Charging power may be derated between 0°C and 15°C. Installation location and operating conditions must comply with the current Fox ESS manual.

Safety and Certification

• Battery Chemistry: Lithium iron phosphate (LiFePO₄)
• Safety: IEC 62619
• EMC: IEC 61000-6-1/2/3/4
• Transport: UN38.3
• Ingress Protection: IP65

Installation and Monitoring

• In a conventional EQ5000 system, the Slave operates under the controller / BMS contained within the EQ5000-M Master
• In a PowerQ / PQ1 system, 2-6 EQ5000-S modules connect directly to the compatible all-in-one inverter
• The plug-and-play modular design helps simplify professional installation and future expansion
• System performance, battery status and energy data can be monitored through FoxCloud when connected to a compatible Fox ESS inverter
• Installation and commissioning must be completed by a suitably qualified installer in accordance with Fox ESS instructions

Expanding an existing system: Fox ESS requires existing and newly added batteries to have closely matched state of charge, with a maximum difference of ±5%. Current warranty guidance states that a formal capacity expansion should be requested within 12 months of the original installation. Confirm expansion suitability before ordering.

Fox ESS EQ5000 Warranty

The Fox ESS EQ5000 battery range includes a 12-year manufacturer warranty, subject to the current Fox ESS warranty terms, online registration, correct system design, professional installation and ongoing connectivity requirements.

Compatibility

The EQ5000-S Slave can be used in conventional EQ5000 stacks with selected Fox ESS high-voltage inverter ranges, including:

• Fox ESS H1 / AC1
• Fox ESS KH / KA Series
• Fox ESS H3 / AC3
• Fox ESS H3 Smart
• Fox ESS H3 Pro

It can also be used directly with the Fox ESS PowerQube / PQ1 all-in-one inverter, which supports 2-6 EQ5000-S batteries without a separate EQ5000-M Master.

Important: Compatibility and permitted battery quantities vary between inverter models. Do not mix EQ5000 modules with EQ4800 or other Fox ESS battery models in the same stack unless Fox ESS has explicitly approved that configuration. Please contact us before ordering if you are expanding an existing system or are unsure which products you require.

Frequently Asked Questions

Fox ESS Integrations

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Product Code: EQ5000-S
Learn More: Fox ESS EQ5000 Battery

Downloads

Datasheet – Fox ESS EQ5000
User Manual – Fox ESS EQ5000

Fox Energy Cube (EC, EQ) Upgrade Guide – How to add a Battery to an Existing System

Order the Fox ESS EQ5000 4.92kWh Slave Battery today from The Eco Supermarket for fast UK delivery, expert technical support and full manufacturer warranty.