Energy Cube modules such as 2900, 4100, 4300 and 4800. Check master/slave role, version and connector.
Open serial guide →Fox ESS battery identification guide
Identify your Fox ESS battery before you buy
Use the model label, serial-number prefix, master or slave role and connector type to identify Fox ECS, EQ and HV2600 batteries—and avoid ordering an incompatible expansion module.
FamilyECS/EQ, HV2600, MIRA, EP or LV
Rolemaster, slave or separate BMS
Versionserial prefix and V1/V2 status
ConnectorType A and Type B do not interchange
Step 1 · identify the family
Fox batteries are not one interchangeable range
Start with the name on the label. The family determines the voltage architecture, control hardware, stacking method and the compatibility rules that apply.
Uses a separate Battery Management System. Identify both the BMS version and battery serial prefix.
Check HV2600 →Fox ESS UK lists one MIRA HV25 iteration, but the complete stack and inverter must still be checked.
Fox guidance →EP3, EP5, EP6, EP11 and EP12 use a separate compatibility route, including model and firmware checks.
Open EP guide →LV52, LV54 and LV5200 are low-voltage products. Do not treat them as interchangeable with high-voltage batteries.
Browse Fox batteries →Step 2 · record the system
The battery model is only part of the answer
Compatibility also depends on the control module, connector, inverter and the other modules already in the stack. Record the complete system before selecting a replacement or expansion battery.
- Battery labelFull model code and serial-number prefix
- Master or BMS labelThe control hardware usually determines the version
- ConnectorPhotograph the physical battery connection
- InverterExact model, generation and firmware if available
- Existing stackQuantity and model of every installed module
ECS / EQ serial guide
Identify the Energy Cube version and connector
The prefixes below follow the Fox ESS UK battery matching guide. Older Eco Supermarket listings may use “EC” in the product title; Fox technical documents generally refer to the family as ECS.
| Battery / role | Version | Connector | Serial-number prefix |
|---|---|---|---|
| ECS2900 master | V1 | Type B | CM292 |
| ECS2900 slave | V1 | Type B | CS292 |
| ECS2900 master | V2 | Type B | TM292 |
| ECS2900 slave | V2 | Type B | TS292 |
| ECS / EQ2900 master | V2 | Type A | JM / KM / 8M / QM292 |
| ECS / EQ2900 slave | V2 | Type A | JS / KS / 8S / QS292 |
| ECS4100 master | V1 | Type B | CM412 |
| ECS4100 slave | V1 | Type B | CS412 |
| ECS4100 master | V2 | Type B | LM412 |
| ECS4100 slave | V2 | Type B | LS412 |
Fox ESS UK lists these as installable in the same compatible Type A stack.
Fox ESS UK lists these as installable in the same compatible Type A stack.
Do not choose by capacity alone. A 2.88kWh module with the wrong master/slave role or connector is still the wrong module. Type A and Type B connectors cannot be mixed within one stack.
HV2600 serial guide
Check the BMS first
The HV2600 uses a separate Battery Management System. The BMS serial prefix is the clearest version check; use the battery serial prefix as a secondary identifier.
HV2600 V1
BMS: 60BBHV1
Battery: 602H262
HV2600 V2
BMS: 60BBHV2
Battery: 60QH262 or 60NH262
Useful links retained
Fox ESS batteries, guides and support
Use the identification checks above before ordering. Stock and prices are shown on the relevant product or category page.
Stackable high voltageEnergy Cube batteriesECS / EQ master and slave modulesBrowse range →
Complete brand rangeAll Fox ESS productsBatteries, inverters and accessoriesShop Fox ESS →
EP high voltageFox EP65.76kWh heated batteryView product →
EP high voltageFox EP1211.52kWh heated batteryView product →
Related guideEP compatibilityEP5, EP6, EP11 and EP12Read guide →
Support directoryFox ESS supportPreparation checklist and contact routesGet support →
Ask before ordering
Send us the labels and we will help check the route
Battery returns are difficult and expensive. Email clear photographs before placing an expansion order and we can help identify the likely family, version and connector requirement.
Common questions
Fox ESS battery identification FAQs
These answers are a starting point. Manufacturer guidance and firmware requirements can change, so verify the whole system before installation.
How do I identify my Fox ESS battery?
Use the physical battery label and, where fitted, the master or BMS label. Record the full model, serial prefix, master/slave role and connector. A photograph is more reliable than a description of the casing.
Can different Fox battery ranges be mixed?
Usually not. ECS/EQ, HV2600, MIRA, EP and LV products use different arrangements. Only use a combination specifically supported by current Fox ESS guidance for the exact system.
Can ECS4300 and EQ4300 be used in one stack?
Fox ESS UK lists ECS4300 and EQ4300 as a supported pairing in a compatible Type A stack. It also lists ECS4800 and EQ4800 as a supported pairing. Confirm the inverter and complete stack before ordering.
What is Type A versus Type B?
They are different physical connector formats used by some ECS battery versions. They are not interchangeable within the same stack, so match both the serial-number version and the connector type.
How do I tell HV2600 V1 from V2?
The BMS prefix is the clearest check: 60BBHV1 is Version 1 and 60BBHV2 is Version 2. Battery prefixes 602H262 indicate V1; 60QH262 and 60NH262 indicate V2.
Can I use the FoxCloud app to identify it?
FoxCloud may show the model, but a clear photograph of the physical label is still the best evidence because it captures the full serial prefix and exact hardware.
Who should confirm a battery expansion?
Use the latest Fox ESS documentation and have the installer or Fox ESS support confirm the full inverter, BMS, battery, firmware and connector combination. Our team can help identify the products before purchase.
Sources & scope
Fox ESS resources
Technical details checked on 21 August 2026.
Not certain which Fox battery you have?
Send the battery, master/BMS and inverter labels before ordering. We will help identify the likely expansion route and flag anything that needs manufacturer confirmation.