Fogstar: Home Batteries, Portable Power Stations and Chargers

Fogstar is a UK battery maker whose range runs from large lithium home storage batteries down to portable power stations and chargers. If you have arrived here because you have seen the name on a home battery, a power station or a charger, the short answer is that Fogstar sells several distinct kinds of kit, and which one matters to you depends on what you are trying to keep running.

For a household thinking about backup power, the main choices are a fixed home battery system (the Fogstar Energy range, from a 5.12kWh stackable battery up to a 64.4kWh modular stack) or a portable power station you can move around the house. The home batteries carry a 6-year warranty with 10 years of UK-based customer service support¹, while the 5kWh Portable Power Station carries a 3-year warranty². Several lines are currently sold out or awaiting a February batch, so check availability before you plan around one.

The single most important thing to understand before buying is compatibility. Fogstar states that it is not on inverter approvals lists because it believes these lists are anti-competitive and limit consumer choice³. That makes checking your own inverter against Fogstar's published guidance a step you cannot skip.

What Fogstar makes for UK households

Fogstar's range falls into four practical groups, and each does a different job in a household.

The home battery range is described by the maker as high-capacity lithium energy storage for residential, commercial and off-grid applications⁷. The 32kWh Battery, for example, offers 32kWh of usable lithium storage and can have up to 16 batteries connected in parallel for expanded storage⁷. The larger 64.4kWh Modular Battery Stack is a high-capacity lithium solution for residential, commercial and off-grid use, with an integrated automatic fire suppression system and an advanced 150A SEPLOS Battery Management System⁸.

For households that want something they can carry, the 5kWh Power Station is described as high-capacity LiFePO4 backup power for homes, workshops, off-grid systems and camping, and it is compatible with optional Fogstar Expansion Battery Packs for additional capacity². If you are weighing up fixed against portable, our guide to backup power at home sets out the trade-offs.

Fogstar's move into advanced energy storage

The direction of the range is towards larger, modular, outdoor-rated systems. The 64.4kWh Modular Battery Stack is IP65-rated for indoor and outdoor installation, uses LiFePO₄ chemistry, and includes an LCD touchscreen for real-time monitoring and system management⁸. The 32.2kWh Modular Battery Stack is likewise IP65-rated for indoor and outdoor installation, with a built-in heating system for reliable cold-weather operation and an integrated automatic fire suppression system⁹.

That IP65 rating matters in a UK context: it means the enclosure is protected against dust and water jets, so siting outdoors is within the maker's description. The 16.1kWh Battery Module is also IP65 rated¹⁰, and the 16.1kWh Expansion Battery Module is described as suitable for indoor and outdoor installations, residential and commercial environments, high-demand inverters and large backup or off-grid installations¹¹.

Fogstar also sells inverters alongside its batteries. The Fogstar x LuxpowerTek Gen3 3.6-6k is an installer-friendly wall-mounted hybrid inverter with up to 97.0% maximum efficiency, built-in Type II AC/DC surge protection, generator input support and a smart cooling system¹¹. All Fogstar inverter options include a Wi-Fi dongle as standard, enabling remote monitoring and system management⁹.

Smaller-format cells and accessories: being phased out but still available

Fogstar's smaller-format cells and accessories, the 18650 and 21700 sizes familiar to people building battery packs, are being phased out, but some items remain on sale while stock lasts. The clearest example is the Fogstar Energy Stackable 48V 5.12kWh Battery, which is listed as a refurbished item with a full 6-year warranty, and all refurbished items are supplied with the full manufacturer's warranty⁶. Optional top cover and wheels are available for it⁶.

The 2kWh Expansion Battery is a LiFePO4 unit at 2048Wh and 51.2V, compatible with the Fogstar 2kWh and 3kWh Portable Power Stations, and it carries a 3-year warranty¹². The 5kWh Portable Power Station is also listed as sold out².

If you are buying during the phase-out, the practical points are:

• Check the warranty terms on refurbished stock. Fogstar states that refurbished items come with the full manufacturer's warranty⁶.
• Check what is in the box. The 16.1kWh Expansion Battery Module, for instance, does not include the stack control unit, LCD interface, base plate or main breaker assembly, and is intended only for use with compatible Fogstar Energy Modular Battery Stack systems already fitted with those parts¹⁰.
• Check the chemistry and voltage match between any expansion battery and the power station it is meant for; the 2kWh Expansion Battery is specified for the Fogstar 2kWh and 3kWh Portable Power Stations¹².

Buying during the phase-out

Availability is the main constraint. The 5kWh Portable Power Station is shown as sold out².

When stock does appear, buy on the specification rather than the label. The Drift LiFePO4 Charger is a fan-cooled LiFePO4 charger, and the V3.0 chargers include a temperature-controlled fan that activates and deactivates when required, for quieter performance⁴. The maker advises retaining your packaging⁴, which matters if a warranty return is ever needed.

For households building a wider emergency kit around a power station, our emergency kit guide and the power cuts guide explain what to keep ready and what to do when the power goes.

Why Fogstar is not on inverter approvals lists

Fogstar's own stated position is that it is not on inverter approvals lists because it believes these lists are anti-competitive and limit consumer choice³. That is the maker's view, and it is worth understanding what it means in practice before you buy.

An approvals list is published by an inverter manufacturer and names the batteries it has tested and approved for use with its equipment. If a battery is not on that list, the inverter maker has not endorsed it. Fogstar's approach is to publish its own compatibility guidance instead, naming the inverter brands its batteries work with and the settings needed.

The maker's guidance is specific. The Fogstar Energy Rack Battery will work with all 48V Victron inverters, requiring a Cerbo GX with a Type B cable into the Cerbo GX CANBUS input and the CAN > Victron protocol selected on the battery screen³. It works with 48V Growatt inverters but not high-voltage ones, and the latest Growatt inverters need a 300V high-voltage battery; the settings are CAN > Growatt protocol, dip switch Number 1 on the master battery, Protocol 51 on the inverter, using the Growatt CAN cable³. It works with 48V Sofar inverters³. GivEnergy inverters are only compatible with GivEnergy batteries³.

There are hard limits to be aware of. Fogstar states that its server rack batteries do not work with high voltage inverters, that Solax inverters only accept extremely high voltage batteries such as their own, and that the Solaredge SE10000H is high voltage and will not work with the 48V batteries³. Fogstar also states that its systems are not compatible with other types or models of battery on the market, and that its batteries will not work with any other make or model of battery, including Pylontech³.

Checking inverter compatibility before you rely on Fogstar kit

Work through compatibility in this order before you commit to a system.

1. Identify your inverter's battery voltage. Fogstar's 48V batteries will not work with high-voltage inverters³.
2. Check the inverter brand against Fogstar's guidance. The maker names Victron, Luxpower, Sunsynk, Solis, Voltronic, Voltacon and others as compatible across its modular stacks⁹.
3. Check the terminal size. The Battery to Inverter Cable Pair uses M8 ring terminals, and Fogstar advises checking that your inverter's battery terminals can accept an 18mm-wide ring terminal, and checking the terminal connections on both your battery and inverter before ordering⁵.
4. Check the cable is the right one. Most Fogstar Energy batteries are supplied with their own battery-to-inverter cables; the M8 pair is intended for additional, replacement or busbar-to-inverter connections⁵. It is not suitable for direct connection to the Fogstar Energy 10kWh, 16.1kWh IP65 or Modular Battery Stack terminals, which use Amphenol connections, nor to the 5.12kWh Rack Battery terminals, which are M6, nor to the Fogstar SNA PRO 6.5K Off-Grid Inverter or the LuxPowerTek GEN-LB-EU 8K and 10K, which use M6 and M10 terminals respectively⁵.
5. Follow the maker's connection order. For correct installation, all negative connections must be made before connecting the positive¹⁴.

The 16.1kWh Battery is not IP rated³, and Fogstar Drift PRO batteries are not IP rated, though the rest of the Drift range is³. If the battery is going outdoors, that distinction decides which model you can use.

Fogstar support, warranty and safety notices

Warranty terms vary by product, so check the one that applies to your kit.

Fogstar publishes grid compliance documents for some inverters: G99 reports by output rating for the GEN3 3.6-6K, G99 reports by output and one G100 document covering all GEN PRO models for the GEN PRO 8-12K, and a G99 report and G100 document for the TriP2 20K. Documents not listed can be requested by emailing customerservice@fogstar.co.uk⁹.

On safety notices, the maker's own instructions are the first place to look. The Drift charger's page carries the heat, water and specification warnings quoted above⁴. For recalls, the Office for Product Safety and Standards issues recalls and alert notices on its website¹⁶, and you can check product recall notices issued by OPSS and contact the retailer where you purchased the product¹³. Recall notifications include information about what the risk is and advice about what you should do if you have bought the product that is being recalled¹⁷. You can also register appliances to receive safety alerts and recall notifications¹⁸, and the fire and rescue service points to Register My Appliance for free recall alerts¹⁸.

If you are building backup power into a wider household plan, start with getting started and the backup power guide, and see self-reliance at home for off-grid power in more depth.