All-in-One Home Battery Systems: Battery, Inverter and Backup in One Unit

An all-in-one home battery system is exactly what the name suggests: the battery cells, the inverter that converts their direct current into the alternating current a house uses, and the control electronics that manage charging all arrive in one enclosure, installed as one unit. GivEnergy describes its All in One as "a single unit comprising the battery and inverter components together"¹, and Sunsynk's All in One ESS Elite "combines a high-performance hybrid inverter, advanced battery technology and intelligent energy management into a single" wall-mounted enclosure². The aim in every case is the same: a battery that stores energy and reduces a household's reliance on the grid, without separate boxes, cabling and controls for each function.

The appeal for a household is simplicity. One box means one installation, one warranty in most cases, one app, and one company to call when something goes wrong. The trade-off is that the inverter power, the chemistry and the expansion ceiling are all fixed at purchase, which is why this page sets out what the current UK ranges offer, what they cost, and where their limits sit. A typical home system is around 10kWh of storage³, and prices for home batteries range from £1,500 to £10,000, with a 5kWh system around £4,600³. Backup in a power cut is possible but depends on a separate changeover device, not the battery itself⁴.

Components housed in one unit

Every all-in-one system packs the same three jobs into one box: storing energy, converting it, and managing it. The battery pack holds the energy. The inverter, or power conversion system (PCS), turns the battery's direct current into the alternating current the house runs on, and in a hybrid unit it also manages the flow from solar panels. The battery management system, the BMS, watches every cell, balancing charge and protecting against over-charge, over-discharge and overheating. SAJ's AS2 series is described by the maker as "an All-in-One residential energy storage solution, seamlessly integrating the PCS, BMS, and battery into a modular, IP65-rated design"⁹.

What varies between products is how much else is included and how the battery itself is built. GivEnergy's All In One 2 communicates over a CAN interface and comes with an inbuilt DC isolator, a component that in older systems was a separate part¹. Across the GivEnergy range the cells use Lithium Iron Phosphate (LiFePO4) chemistry, which the maker states is cobalt-free and offers enhanced thermal stability, longer lifespan and improved safety¹⁰. The makers state that the batteries offer 100% depth of discharge over a 10-year lifespan, so the full rated capacity is usable rather than a portion held in reserve, with 100% recyclability claimed as well².

The comparison householders often meet is with heat pumps, where the equivalent idea is familiar: a monobloc air source heat pump "combines all components in one unit" and needs no separate indoor unit¹¹. The principle is the same. What the manufacturer puts in the box at the factory, the installer cannot change afterwards, so the specification you buy is the specification you live with.

Integrated units or separate battery and inverter: choosing for your home

The alternative to an all-in-one is a two-part build: a separate battery, or a stack of battery modules, connected to a separate inverter. GivEnergy's own system documentation shows both routes in its range, pairing its AC coupled inverter with any low-voltage battery, and its three-phase hybrid inverter, described as "a battery plus solar inverter in one unit", with any high-voltage stackable battery¹. Its battery range runs from a 5.12kWh module through high-voltage stackable units of 10.2, 13.6, 17.0 and 20.4kWh, alongside the All in One at 13.5kWh¹.

A single-box system suits a home that wants one installation, one warranty and one point of contact. Sunsynk markets the unified warranty of its All in One ESS Elite as a benefit², and the reduced wiring of a floor-mounted stackable unit shortens installation time¹². A separate build suits a home that wants to choose the battery and inverter independently, to size each part for a specific job, or to replace one part later without losing the other. The trade-offs run both ways:

• All-in-one: one enclosure, one warranty, one app, faster installation; but inverter power and expansion limits are fixed at purchase.
• Separate build: battery and inverter can be sized and replaced independently; but two products mean two warranties to track and more wiring on site.

For a household thinking about energy independence, the difference is less about capability than about flexibility. Both routes can charge from solar, charge from the grid at cheap times, and provide backup with the right changeover device. The all-in-one simply locks those decisions earlier. More detail on the two coupling approaches is in AC and DC coupled systems, and on the wider decision in home battery storage.

Storage size and output, ranging from 10kWh to 40kWh

The useful starting point is what a home actually needs. Energy Saving Trust states that "battery storage capacity is measured in kilowatt hours (kWh) and a typical home system might be 10 kWh"³, and Solar Energy UK reports residential battery systems as "typically in excess of 10kWh (well over five average washing machine cycles)"¹³. Capacity is the amount stored; power, measured in kW, is how fast it can be delivered, and an all-in-one fixes both when it leaves the factory.

At the top of the range, GivEnergy's All In One 2 reaches "up to 40.5kWh of capacity" once its expansion batteries are added⁵, with the base unit at 13.5kWh and each expansion battery adding 13.5kWh¹⁴. Below it, GivEnergy's high-voltage stackable batteries come in 10.2 kWh, 13.6 kWh, 17.0 kWh and 20.4 kWh sizes, so a household can match storage to its usage¹. GivEnergy positions the All In One 2 as a unit that "handles heavy energy loads, while remaining one of the most affordable battery storage systems in the market"¹⁰, a maker's claim that should be read alongside the independent cost figures later on this page.

How much capacity a household needs depends on what it wants the battery to do. Jackery's guidance distinguishes use cases by size, putting whole-house backup plus EV charging at "20+ kWh"¹⁵. The Climate Change Committee notes that at household level, innovation in home battery technology, vehicle-to-everything (V2X) and solar "can provide households with additional backup options during power outages"¹⁶, which is one reason larger capacities are becoming common. Sizing is covered in full in what size home battery you need, and the difference between nominal and usable capacity in battery capacity and usable capacity.

Aligning your setup with single-phase or three-phase supply

Most UK homes have a single-phase electricity supply, and most domestic batteries are built for it. The question of three-phase arises when capacity or generation grows large. Northern Ireland Networks states the rule plainly for its area: on a single-phase supply, "above this capacity a three phase supply is required", with the threshold set at 17kW¹⁷. That is well above the power rating of any domestic all-in-one, so a three-phase supply is not a requirement for a large battery by capacity alone.

A householder can check the supply at the meter. OpenEnergyMonitor's guidance is that "if you have eight reasonably thick cables connecting to the meter, four of which go to your consumer unit or fuse-board", together with a 3-pole or 4-pole linked MCB, the supply is three-phase¹⁸. Homes with three-phase supplies, sometimes larger properties or those with heavy equipment, need an inverter that matches, and makers provide them: GivEnergy's three-phase hybrid inverter pairs with any high-voltage stackable battery in its range¹.

For the independence picture, the supply type does not change what the battery does, only how it connects. What matters more is that the installation is notified to the network operator under the G98 or G99 process, covered in telling the network operator about a home battery.

Why LiFePO4 chemistry matters for safety

Every all-in-one system sold in the UK ranges covered here uses lithium iron phosphate, or LiFePO4, as its battery chemistry. GivEnergy's All In One 2 lists its battery type as "Li-ion - LiFePO4"⁶, and its expansion battery uses the same chemistry⁸. Sunsynk's Elite system is likewise a LiFePO4 battery system¹², and BRE's ZEDpods low-energy home system uses a LiFePO4 battery store¹⁹.

The makers' case for the chemistry is consistent. GivEnergy states that "LiFePO4 batteries are cobalt-free, offering enhanced thermal stability, longer lifespan, and improved safety"²⁰, and describes the expansion battery's chemistry as "non-flammable, 99% recyclable"⁸. On recyclability the makers' own pages differ slightly in emphasis, with GivEnergy also claiming "100% recyclability" for its batteries²⁰; both figures are maker claims rather than independent assessments, and they differ, so treat the recycling rate as the maker's estimate rather than a settled number.

What LiFePO4 means in practice is a chemistry that is more stable under fault conditions than the cobalt-based lithium chemistries used in some older products and in most electric cars, and one that does not contain cobalt at all. It is not a guarantee of safety: any battery stores a large amount of energy, and installation standards, siting and fire precautions still apply in full, as covered in home battery fire safety and battery installation standards. The chemistry is compared with the alternatives in home battery chemistries.

Why a changeover switch, not the battery, determines backup supply

This is the point most often misunderstood. A battery, all-in-one or otherwise, cannot power a house during a grid cut on its own, because it must first disconnect the home from the incoming supply so that electricity does not flow back onto the network and endanger engineers. That disconnection and reconnection is done by a changeover device, usually called a gateway or backup interface, which is often a separate box beside the battery.

GivEnergy's product pages are explicit about the pairing. The All In One 2 "delivers seemless switchover for backup power during blackouts when paired with a Gateway 2"⁵, and the Gateway 2 "enables full whole-home backup and advanced load control when paired with the All-in-One 2 system"⁵. The original All In One works the same way: "paired with the relevant Giv-Gateway, it guarantees uninterrupted power by seamlessly switching between the grid and battery storage"¹⁰. Fox ESS's Evo All-in-One includes a whole home backup gateway⁷.

Independent guidance adds the necessary caution. Which? states: "If you're looking to protect yourself against power cuts with a home battery, not all systems are suitable." Its advice is to ask your installer whether your battery will work in a power outage, and for how long⁴. The capacity question then follows: whole-house backup with EV charging is the use case Jackery puts at 20+ kWh¹⁵, and how long a given capacity lasts depends entirely on what the household runs during the cut. The detail is in battery backup in a power cut and backup interfaces.

Automated charging on smart energy tariffs

An all-in-one earns much of its value not from solar alone but from buying electricity when it is cheap and using it when it is expensive. Energy Saving Trust is direct about the prerequisite: "To benefit properly from smart appliances, electric vehicles and home batteries you need to be on a smart tariff"²¹. Its tariff advice makes the same point from the other end: "Do you have (or plan to get) an EV, heat pump or home battery? These make smart tariffs much more valuable."²²

The automation is built in. GivEnergy's installer guidance describes the operating logic in one line each: "Charge when energy is free or cheap" and "Discharge when energy is expensive", adding that "the system can automatically charge and discharge based on the times that will save you money" and that "GivEnergy batteries will work seamlessly with any smart tariff"²³. Those are the maker's claims for its own products, but the pattern is general: Energy Saving Trust explains that with a battery and no solar panels, "you'll stop charging the battery when it's full, and discharge it when the next cheap tariff period ends", automatically³.

One check matters before committing. Which? advises: "Is the tariff compatible with your battery? Some only work with specific systems."²⁴ The same compatibility question applies in the EV charging world, where products differ in which suppliers' tariffs they support²⁵, and Octopus's smart EV tariffs work via an app customers download²⁶. The full picture on stacking a battery with time-of-use tariffs is in batteries and smart tariffs.

What published pricing reveals

No maker publishes a fixed price for an all-in-one system, so installed prices are quoted by installers. The independent figures that do exist give the scale. Energy Saving Trust puts home battery costs at £1,500 to £10,000, "but the cost for a 5kWh battery system is around £4,600"³. A Scottish housing retrofit study modelled a single 8kWh battery system "at a cost of £4,350" across all house types²⁷. At the larger end, Jackery's guidance estimates a whole-house backup plus EV charging system at "£12,000+"¹⁵.

Against those costs sit savings and, for some households, funding. Octopus Energy calculations put a medium-use household with a 10-panel system and a 5kWh battery as saving "between £822 and £1,069 per year, depending on their tariff"². The UK government's Warm Homes Plan, announced in January 2026, provides fully funded solar panels and battery installations for low-income households, covering "the full average cost (currently £9,000-£12,000)"²⁸. Birmingham City Council's Switch Together scheme lets households register to have battery storage added to existing solar panels²⁹.

The honest overall position is the one the Centre for Sustainable Energy gives: batteries "may save on imported electricity costs, but they're currently very expensive"³⁰. Payback depends on tariff, usage and solar generation, and is worked through in battery payback and savings and home battery cost.

How long they last and what the warranty covers

Independent lifespans cluster around a decade. Energy Saving Trust gives "about 10 to 12 years" as the typical battery lifespan³. A parliamentary research briefing on domestic energy storage gives "around 10 to 15 years"³¹. The Centre for Sustainable Energy uses a slightly lower range of 8 to 12 years³². These are ranges for the technology in general, not for any one product.

The maker warranties on current all-in-one products sit at or above those figures. GivEnergy covers the All In One 2 for 15 years⁶ and its expansion battery for 15 years⁸. Fox ESS covers the Evo All-in-One with a 12 year warranty⁷. Sunsynk markets a unified warranty for its All in One ESS Elite, covering the integrated unit as one². GivEnergy's wider product range carries warranties spanning 12 years²³.

Two cautions apply. First, a warranty is a set of conditions as well as a term: registration, installation by a certified installer and monitoring requirements all commonly apply, and the detail is in home battery warranties. Second, the battery's working life depends on how it is used. Energy Saving Trust warns that "the system should never let your battery discharge to zero, as this can significantly reduce the life of the battery"³. Degradation over time is covered in cycle life and degradation.

Adding more capacity later and the limits involved

All-in-one systems are expandable, but within a ceiling fixed by the base unit. GivEnergy's All In One 2 accepts expansion: "up to two expansion batteries can be added per AIO2 system"⁸, each a 13.5kWh unit "designed to increase the storage capacity of the All-in-One 2 system"¹⁴, which is how the range reaches 40.5kWh⁵. Sunsynk's Elite is a floor-mounted, stackable system¹², built to grow in the same way.

The limit matters at purchase. A household that buys a small all-in-one and later finds it needs more storage can add only what the base unit allows, and no more. That is the practical difference from a fully modular stack, where the battery modules and the inverter are sized independently, a distinction explored in modular and stackable battery systems and adding more batteries later.

Expansion also interacts with the rest of the system. Battery storage can be added to existing solar panels to maximise the benefits of the system, as Birmingham's Switch Together scheme allows households to do²⁹, and a larger battery changes what a household can back up in a cut, since whole-house backup with EV charging is the use case Jackery places at 20+ kWh¹⁵.

UK supply and discontinued models

The current all-in-one ranges covered on this site are available in the UK. Which? lists Samsung SDI's all-in-one as available "in the UK" and the Enphase AC Battery "via UK installers"⁴. GivEnergy, Fox ESS, Sunsynk and SAJ all sell their integrated units through UK installers, and each has a dedicated page here: GivEnergy All in One, Fox ESS home batteries, Sunsynk and SAJ.

The market also moves quickly, and withdrawn products are worth knowing about. The Livoltek iPower AC Coupled all-in-one is listed as discontinued³³, and GivEnergy's Wi-Fi Dongle has been discontinued³³. A discontinued accessory is an inconvenience; a discontinued system is more serious, because cloud services, apps and warranty support can become uncertain once a product line ends. Wondrwall, for instance, states that full app reporting is currently available for its V.1 battery systems, with V.2 All-in-One compatibility expected in Q4 2026³⁴, which shows how app support can lag or depend on product generation.

The reality of energy independence gains

An all-in-one battery reduces a household's dependence on the grid in a real, measurable way: it stores solar energy that would otherwise be exported, and it shifts consumption from expensive hours to cheap ones. GivEnergy's own framing is that its batteries "store renewable energy and reduce your reliance on the grid"¹⁴, and the All In One 2 is stated to save up to 85% on bills as it maximises solar energy and can charge from the grid⁶, a maker's figure for its own product. The Climate Change Committee's view of the direction of travel is that home batteries, V2X and solar together "can provide households with additional backup options during power outages"¹⁶.

What remains is equally plain. The system still needs the grid to charge when solar is short, and a supplier to sell the household electricity on a tariff. It depends on the manufacturer for warranty support, spare parts, app and cloud services, and a discontinued model can leave that support thinner than a buyer expected. Backup in a cut depends on a gateway that may be an extra box and an extra cost⁴. And the battery itself is a consumable with a working life of roughly a decade³, after which it faces recycling³⁵.

None of that is an argument against the technology; it is the honest shape of it. An all-in-one system is one of the simplest ways to make a home more self-sustaining, provided the household buys the capacity, the backup device and the warranty terms it actually needs, and understands which dependencies remain. The wider picture is in home batteries and household energy independence.