Fogstar Energy Home Batteries: Modular Stacks and ECO Range

Fogstar Energy is the home storage arm of Fogstar, a UK company that has been supplying and designing lithium battery solutions for a decade and marked that milestone in 2026¹. It sells direct to householders rather than through an installer network, and the range runs from a 10kWh battery at £1,599.99 to a 64.4kWh modular stack at £6,999.99². The entry point for most homes is the 16.1kWh ECO battery at £1,949.99, which the maker prices at £121.12 per kWh³.

The technology is consistent across the range: 48V nominal systems built on LiFePO4 cells, with a 200A PACE battery management system on the 16.1kWh unit and cycle life quoted at up to 8,000 cycles at 91% depth of discharge⁴. Fire suppression and battery heating appear on the newer models, and the IP65 modular stacks are rated for indoor and outdoor installation⁶.

What this buys a household is storage it owns outright, bought at a published price with no installer margin built in. What it does not buy is a complete system: these are batteries, and the inverter, the installation and the electrical sign-off sit outside the box. The dependence that remains is on the inverter maker, on the installer who wires it, and on the grid the battery is charged from.

Fogstar Energy: the company behind the batteries

Fogstar was founded by Ben Facer to supply genuine lithium-ion cells to the UK market, and the company describes 2026 as marking a full decade of supplying and designing lithium battery solutions¹. That origin in cell supply matters to how the business presents itself: the emphasis throughout its guidance is on cell provenance and traceability rather than on system integration. Fogstar states that it fully controls its manufacturing process, with a directly employed team overseeing component sourcing, assembly and quality control¹⁰.

The home storage range sits alongside a leisure battery business, the Drift range, which was launched in 2022 and has since been extended¹. Fogstar Energy is the brand under which the storage batteries are sold, and the maker is named as Fogstar Energy on the product pages themselves¹¹. The 16.1kWh battery is described as UK-designed¹².

The company sells direct, which is the single most important commercial fact about it. There is no installer network standing between the maker and the buyer, and no published installed price, because installation is not part of what Fogstar sells. A householder buys a battery at a listed price and then arranges an electrician or installer separately. That keeps the hardware cost visible and comparable, and it moves the responsibility for a safe, compliant installation onto the buyer.

Support is UK-based and long-running: the modular stack pages state that the products are backed by ten years of UK-based customer service support⁷. Wholesale enquiries run through a separate address and a dedicated wholesale site, while general customer service for the batteries runs through customerservice@fogstar.co.uk¹³.

The range at a glance: ECO, IP65 modular stacks and larger stacks

Fogstar Energy's catalogue spans 5.12kWh up to 1.23MWh in size, which covers everything from a single small battery to commercial-scale banks². For a home, three families matter.

The ECO range is the simplest: a fully assembled, commercial-grade energy storage unit built for homes and small commercial installations, sold as a single box². The IP65 modular stacks are the expandable option, where each 16.1kWh module forms part of a system that can be configured from a single module up to a 64.4kWh stack⁷. Above that sit the larger rack and cabinet systems, including a 30kWh rack bundle in a glass cabinet, intended for residential and commercial applications and described as suited to plant rooms, garages and dedicated energy storage spaces¹⁴.

Prices are the maker's published figures and the VAT position is not stated on them. Bundles that pair a battery with an inverter are priced separately, from £2,451.79 for a 16.1kWh ECO bundle and from £2,681.79 for an IP65 16.1kWh bundle¹⁷. A 16.1kWh battery with an inverter is listed at £2,909.03, reduced from £3,161.99⁴.

The 16.1kWh ECO battery: the entry point at £1,949.99

The ECO 16.1kWh battery is the model most households will meet first. It is a fully assembled, commercial-grade energy storage solution built for homes and small commercial installations, priced at £1,949.99, which the maker works out at £121.12 per kWh³. It carries a six-year manufacturer's warranty backed by ten years of Fogstar customer support³.

Inside, the maker specifies fully matched and balanced Grade A 314Ah cells, paired with a smart 200A BMS that integrates with Victron, Luxpower and Sunsynk inverters⁸. Rated charge and discharge current is 200A at 25 degrees C, and cycle life is quoted at 8,000 cycles at 91% depth of discharge, measured at 25 degrees C with a 50A charge and discharge current³. Fire suppression is included: an automatic heat-activated aerosol system provides rapid response protection inside the battery³.

That combination of a published per-kWh figure and named inverter compatibility is what makes the ECO range legible to a householder comparing options. The per-kWh price is the number to hold onto, because it is the only figure in the range expressed that way, and it lets a buyer see how the larger stacks compare without doing the arithmetic themselves.

The limits are worth stating plainly. The ECO is a battery, not a system: no inverter, no changeover for backup, no installation. Inverter compatibility is stated for three brands, and a household with a different inverter would need to check the protocol list rather than assume. The 200A rating sets the power ceiling, which is a separate question from capacity and is covered in battery power ratings.

The IP65 modular stack: 16.1kWh modules that build to 64.4kWh

The modular stack is Fogstar's most popular battery to date, and the design logic is straightforward: one 16.1kWh module is the building block, and a stack can be configured from a single module up to 64.4kWh⁸. The 64.4kWh stack is built from four individual 16.1kWh modules⁶.

Each module is rated at 16.1kWh with a 314Ah capacity, configured 16S1P, and the enclosure is IP65 rated for indoor and outdoor installation⁷. A module measures 830mm long, 450mm wide and 449mm high, and weighs 148kg⁷. The stack version comes with a stack control panel and base, and is supplied with pre-terminated 95 mm² battery power cables, battery-to-battery cables with Amphenol connectors, and a 1.5m communication cable⁷.

Cycle life is quoted at 8,000 cycles at 91% depth of discharge, and the fire suppression is a built-in, heat-activated aerosol system that the maker describes as needing no ongoing maintenance⁷. A single 16.1kWh expansion module is sold separately at £2,049.99 for households adding capacity to an existing stack¹⁸.

The intermediate sizes are worth knowing because they show how the arithmetic works. A 32.2kWh stack uses two modules and is expandable to 64.4kWh with additional stacks, and a 48.3kWh stack uses three modules with the same expansion ceiling¹⁶. The 32.2kWh stack is IP65 rated for indoor and outdoor installation and carries a six-year warranty with ten years of UK customer support¹⁶.

Availability is the practical constraint. The 16.1kWh, 32.2kWh and 64.4kWh stacks were all showing a next available batch arriving in December at the time of writing, so a household planning an installation around one of these should expect a lead time rather than next-day delivery⁷. The expansion path itself is covered in modular and stackable battery systems.

The 32kWh battery and outdoor cabinet options

The 32kWh battery is the largest single-box unit in the range, priced at £3,499.99⁵. It is rated at 32kWh nominal and 32kWh usable, and it is expandable up to 16 units, which is the widest scalability figure published for any single Fogstar product⁵. It carries an integrated automatic fire suppression system and built-in battery heating that enables safe charging down to minus 10 degrees C⁵. Inverter compatibility is stated for Victron, Luxpower, Solis, Sunsynk and Voltacon, and cell configuration is 16S2P⁵. A JK 2A active balancer handles cell management²⁰.

The heating is the detail that matters most for UK siting. A battery in an unheated garage or an outdoor cabinet faces winter temperatures that would otherwise block charging, and the maker's stated minus 10 degrees C charging floor is the figure to check against a proposed location. The general principles are set out in ventilation, temperature and operating conditions.

For outdoor siting, Fogstar sells an IP56 outdoor battery cabinet that takes either four 5.12kWh batteries for 20.48kWh or eight for 40.96kWh²¹. The cabinet is a housing rather than a battery, so the capacity comes from the modules inside it. A 30kWh rack bundle in a glass cabinet is also offered, described as designed in the UK and intended for plant rooms, garages and dedicated energy storage spaces¹⁴.

The distinction between IP65 and IP56 is worth noting: the modular stacks are IP65, the outdoor cabinet is IP56, and both are described as suitable for outdoor use. Neither rating is a statement about thermal performance, which is governed by the heating system instead.

Specifications: 48V, 314Ah cells, 200A BMS and 8,000 cycles

The specification pattern across the range is consistent enough to summarise. All Fogstar battery options, both pre-assembled and DIY, use LiFePO4 technology². The 16.1kWh 48V battery runs at 48V nominal with 16.1kWh usable capacity, an advanced 200A PACE battery management system, and up to 8,000 cycle life⁴. The ECO 16.1kWh battery uses Grade A 314Ah cells and a smart 200A BMS⁸. The 5.12kWh rack battery uses Grade A LiFePO4 cells and a PACE 100A BMS¹⁴.

The 51.2kWh figure appears in the case study material, where the 16.1kWh battery is described as operating at 48V with a 51.2V nominal voltage²³. That is the same pack described two ways, and the product pages use 48V throughout.

The 8,000-cycle figure is the headline durability claim, and it is consistently tied to a depth of discharge rather than quoted bare: 91% on the 32kWh battery, the 64.4kWh stack and the modular stacks⁵. Cycle life claims of this kind are covered in more detail in battery cycle life and degradation.

Fire suppression, heating and the 95% depth of discharge

Fire suppression is standard across the Fogstar Energy range rather than an optional extra. The 32kWh battery has an automatic, heat-activated aerosol fire suppression system built directly into the battery enclosure⁵. The 64.4kWh stack and the 16.1kWh IP65 module both use a built-in, heat-activated aerosol system that the maker says provides fast, automatic internal protection with no ongoing maintenance⁶. The 10kWh battery and the ECO 16.1kWh battery use the same approach, described as an automatic heat-activated aerosol system providing rapid response protection inside the battery¹⁵.

Heating appears on the 32kWh battery, which enables safe charging down to minus 10 degrees C, and on the 16.1kWh IP65 battery, where heating is listed alongside fire suppression and a ten-year warranty⁵.

Depth of discharge is where the published figures diverge, and the divergence is worth understanding. The cycle life ratings are quoted at 91% depth of discharge across the range⁵. Separately, Fogstar's firmware page states that beta firmware enables increased battery utilisation down to a total of 95% depth of discharge¹³. That is a firmware-dependent figure rather than a specification of the hardware as shipped, and it applies to beta builds. A household reading 95% should treat it as a capability available through a firmware path, not as the rating the cycle life figures are quoted against. The distinction between nominal and usable capacity is covered in battery capacity and usable capacity.

Warranty, support and what owning one means for energy independence

Warranty terms vary by model, and the variation is real rather than cosmetic. Most Fogstar Energy products carry a six-year warranty with ten years of customer support: the 32kWh battery, the 10kWh battery, the 64.4kWh stack, the 32.2kWh stack, the 16.1kWh expansion module, the IP65 10kWh battery and the stackable 5.12kWh battery all follow this pattern⁵. The ECO 16.1kWh battery carries a six-year manufacturer's warranty backed by ten years of Fogstar customer support³. The 16.1kWh IP65 battery is the outlier, listed with a ten-year warranty⁸. The 12V DIY kit is at the other end, with a one-year warranty on all components, BMS and case²⁵.

Support is UK-based across the range, and the modular stack pages state ten years of it⁷. That is a service commitment rather than a warranty term, and the two should not be read as the same thing.

On independence, the position is mixed and worth stating precisely. A Fogstar battery is bought outright at a published price, with no subscription, no cloud service in the purchase path and no manufacturer lock-in on the hardware itself. The BMS communicates over CAN and RS485, which is an open protocol pair rather than a proprietary one¹⁶. That is a genuine degree of independence: the household owns the asset and the data path is standard.

What remains is the rest of the system. The battery needs an inverter, and compatibility is stated for named brands rather than universally⁵. It needs an installer for the electrical work, and the standards governing that are set out in installation standards. It needs the grid to charge from unless there is on-site generation, and it needs a network operator notification in most cases, covered in G98 and G99. Fogstar's own charger is marked for use with Fogstar products only, which is a small but real tie²⁶.

For a household weighing storage, the Fogstar proposition is a low headline cost per kWh with a long support commitment and a short warranty relative to the cycle life claim. The gap between a six-year warranty and an 8,000-cycle rating is the thing to examine, and home battery warranties explains how those terms are usually structured.