Product cover
Protection against covered defects in materials or manufacture. Find out whether the inverter, controller and communications hardware have the same term as the battery.
Choose your battery with confidence
Home battery warranties compared: 12 brands and the companies behind them
A battery is a long-term investment. Look beyond the headline years: compare guaranteed capacity, usage limits, the business standing behind the promise and how a repair would happen.
Sources checked: 8 October 2026
What makes a reassuring battery warranty?
A useful warranty fits how you intend to use the battery, has clear conditions and comes with a practical UK claims route. A well-established manufacturer can provide reassurance, but its history and size cannot guarantee future solvency or turn a manufacturer’s promise into insurance.
This is a shortlist of 12 brands UK buyers may encounter, rather than a ranking of the “best” warranties or a claim to cover every model. Battery models, purchase dates and regional terms matter. Ask for the precise UK warranty attached to your quote.
Performance cover
A minimum remaining capacity under specified conditions. A 60%, 70% or 80% floor is a contractual threshold, not a forecast of what your particular battery will retain.
12 home battery warranties at a glance
The capacity figures below use each document’s own basis: nominal, initial or usable energy. They are not all measured identically. Where years, cycles or throughput compete, the performance cover can end at the first applicable limit.
On a phone, swipe the table sideways. Follow the links for conditions, exclusions and the complete claim procedure.
| Brand and example | Headline duration | Capacity protection | Important conditions |
|---|---|---|---|
| Tesla Powerwall (current European warranty) | 10 years | 80% of initial 13.5 kWh | Unlimited cycles for solar self-consumption, time-based control and backup; other uses have a 37.8 MWh limit. Registration and internet conditions apply. Read applicable warranty |
| BYD Battery-Box Premium HVS / HVM | 10 years | 60% usable energy | Time or model-specific throughput, whichever comes first. HVS 10.2: 30.82 MWh. An approved compatible inverter matters. Read applicable warranty |
| Enphase IQ Battery 5P, UK version | 15 years or 6,000 discharged cycles | 60% at the end of the term | Whichever limit arrives first. Gateway, current transformers and communications kit have shorter cover; do not assume the whole installation has 15 years. Read applicable warranty |
| Huawei LUNA2000 S1, 6.9 kWh module | Up to 15 years | 60% for this module | 5 basic plus 10 advanced years; 28.84 MWh throughput limit. Advanced cover requires FusionSolar connectivity. The 5 kWh S1 module has different terms. Read applicable warranty |
| Sigenergy SigenStor BAT, European warranty | 10 years | 60% usable energy | Time or throughput first: BAT 8.0 (7.8 kWh usable) has 27.30 MWh. Internet disconnection can reduce cover. EV charging module cover differs. Read applicable warranty |
| Fox ESS EP11, UK / Ireland warranty v4.2 | 5 years; free extension to 10 | 70% nominal energy | Extension requires registration and FoxCloud connection under the stated rules. Performance also has a model-specific throughput limit; other Fox models differ. Read applicable warranty |
| Sungrow SBR128, UK distribution warranty | 10 years, subject to throughput | 60% state of health | SBR128: 53.76 MWh at the 60% endpoint; the document also specifies an earlier 80% band. Check the model’s schedule and applicable UK version. Read applicable warranty |
| Pylontech US5000, European document EU20WS7055 | 10 years in the reviewed document | 60% nominal energy in the definition | The document also mentions an 80% usable-energy figure in its compensation wording. Get written clarification; do not substitute advertised cycle life for warranty cover. Read applicable warranty |
| AlphaESS SMILE G3, UK December 2024 | 10 years | 80% in the performance table | Table says unlimited cycles for specified home uses, but an earlier clause refers to 3.11 MWh per kWh and 70% SOH. Ask AlphaESS to reconcile these before purchase. Read applicable warranty |
| myenergi libbi complete system, product warranty v4 | 10 years | No explicit capacity floor identified in this product warranty | Applies to purchases from 11 November 2025. Battery, hybrid inverter and controller must operate together as the approved system. Request any separate performance guarantee. Read applicable warranty |
| sonnen sonnenBatterie, GB manufacturer guarantee | 10 years, 10,000 full cycles or throughput limit | 70% nominal capacity | Earliest limit applies; throughput is 8,500 kWh per kWh of net capacity. Operator may pay labour/travel costs; current-value remedies can apply. Read applicable warranty |
| SolarEdge Home Battery 400V / Energy Bank | 10 years | 70% | Unlimited cycles under approved applications. SolarEdge inverter and monitoring conditions apply; labour, travel and removal/reinstallation are excluded. Read applicable warranty |
Tom Solar’s view
Longer cover is attractive when the conditions fit your use. Enphase’s 15-year headline, Huawei’s extended cover and Tesla’s capacity floor all deserve attention, but they answer different questions. A ten-year warranty with a generous usage allowance and a clear service route may suit your household better than a longer promise with restrictive conditions.
For batteries charged overnight and used every day, compare the permitted charging applications and throughput allowance before comparing the years alone.
Why throughput matters for overnight charging
Throughput is the accumulated energy counted under the warranty. One megawatt-hour (MWh) equals 1,000 kilowatt-hours (kWh). A cycle is measured as the manufacturer defines it; it does not necessarily mean every partial charge is one full cycle.
As an illustrative calculation, a 30 MWh allowance divided by 10 kWh discharged each day gives 3,000 days — about 8.2 years. Discharging 5 kWh a day gives about 16.4 years, although a ten-year time limit would still arrive first. This simplified calculation assumes the document counts discharged energy that way; it is not a life prediction or a calculation for every brand.
The battery does not suddenly stop working when its warranty expires. The point is to match cover to expected use, including overnight tariff charging, solar charging, backup reserves and any grid-service participation.
Two documents deserve clarification before purchase
AlphaESS G3: the performance table and earlier claim conditions use different capacity and throughput wording. Pylontech US5000: the reviewed document’s capacity definition and compensation wording also differ. Ask for written confirmation of the applicable capacity threshold, usage allowance and remedy for your purchase.
The companies behind the batteries
These establishment dates describe the business, not how long it has manufactured the battery in your quote. Group revenue, employee numbers and deployment totals indicate scale; they do not measure UK customer service or independently prove financial security.
Tesla
Tesla Inc group; a large listed vehicle and energy business. Reported 46.7 GWh of energy-storage deployments in 2025 across its storage products, not Powerwall alone.
BYD
Started in rechargeable batteries. A large listed battery and vehicle group, reporting RMB 777.1 billion revenue for 2024. The reviewed European warranty names BYD Smart Device Hungary Kft.
Enphase
Enphase Energy Inc is a listed energy-technology group. Its 2026 proxy reports 2,872 employees and more than 86 million microinverters shipped since inception; those are group metrics.
Huawei
Huawei group reported CNY 880.9 billion revenue in 2025. Digital Power sits within a much broader technology business; that scale does not mean its domestic batteries date back to 1987.
Sigenergy
Sigenergy Technology Co Ltd is a comparatively young specialist. Its corporate sustainability report dates establishment to May 2022. Evaluate its UK support alongside the product’s features.
Fox ESS
Fox ESS is a younger inverter and storage manufacturer with international operations. Assess the named warranty provider, registration process and UK repair arrangements rather than assuming a shareholder guarantees claims.
Sungrow
Sungrow Power Supply Co Ltd is an established listed power-electronics manufacturer with global solar and storage operations. Its inverter history is longer than the history of its current home batteries.
Pylontech
Pylon Technologies Co Ltd is a specialist battery manufacturer, listed on Shanghai’s STAR Market in 2020. Corporate history and listing are useful evidence of an established business, not insurance.
AlphaESS
A storage specialist with a UK subsidiary. Its regional company profile reports over 200,000 installed systems in more than 130 countries; this is a manufacturer-reported footprint, not a financial audit.
myenergi
A UK-founded home-energy business. Energy Impact Partners announced a £30 million investment in 2023. Investment backing is distinct from a parent-company guarantee or insured warranty.
sonnen
An established German home-storage specialist. Energy-Storage.news reported Shell’s sale of sonnen to TIVEN in August 2026, citing Shell confirmation. Older descriptions of Shell ownership should not be relied on.
SolarEdge
SolarEdge Technologies is a listed international solar-technology group (NASDAQ: SEDG). Compare the actual battery and inverter warranties separately, even where they share a brand.
For each quote, identify the legal warranty provider and its UK contact details. A parent group, shareholder or investor is not automatically liable for a subsidiary’s warranty.
A current caution for GivEnergy buyers and owners
GivEnergy is not included in the 12-brand shortlist above. Companies House lists GivEnergy Ltd (11571089) as in administration at the date of this review. Existing batteries may still operate, but do not treat an advertised hardware warranty as dependable reassurance without checking who can fulfil it.
Corporate status is specific to the legal entity; it should not be generalised to every business using a related name. Owners should retain paperwork and investigate any separate rights against their installer or eligible payment provider. See our warranty and buyer-protection guide.
Your battery warranty checklist
- Get the exact model and document. Record its version, region, start date and purchase-date rules.
- Separate product and capacity promises. Ask what covers the battery, inverter, controller and installation workmanship.
- Check years, cycles and throughput. Confirm which limit arrives first and whether your expected daily use fits.
- Confirm overnight charging is permitted. Also check restrictions on third-party control and grid-service schemes.
- Complete registration and connectivity requirements. Keep evidence that the installer has done this.
- Check siting and temperatures. Outdoor suitability, coastal exposure and ventilation must match the installation manual.
- Find out who pays for a repair. Ask about labour, travel, freight, removal, reinstallation and replacement equipment.
- Keep a direct claims route. Know how to reach the manufacturer if the original installer stops trading, and whether cover transfers when you sell.
Common battery warranty questions
Is a 15-year warranty always better than a ten-year warranty?
No. Compare the capacity floor, cycle or throughput allowance, permitted uses and repair costs alongside the term. The better fit depends on the battery and how you will use it.
Does a bigger company guarantee a safer warranty?
Company history and scale provide useful context, but neither guarantees future claim payment. Check the named warranty provider and whether any separate protection actually covers the risk you are concerned about.
Will my battery stop working when its warranty ends?
No. Warranty expiry is the end of specified contractual cover, not a scheduled failure date. Useful life depends on the equipment, usage and operating conditions.
Can I compare capacity guarantees directly?
Only with care. Manufacturers may use different initial, nominal or usable-capacity definitions and test methods. Ask your installer to explain both the guaranteed percentage and the energy it represents for your exact system.
Start with your home
Which solar and battery system fits your household?
A free initial roof check helps start a conversation about your home’s solar potential. From there, compare a suitable system, realistic use and clear written warranties together.
Check My Roof FreeAbout the sources
Warranty and company sources are linked beside each entry. This review summarises documents available on 8 October 2026; some carry earlier issue dates and apply to specific purchases. Pylontech’s manufacturer document is hosted by a distributor. Company footprint figures are attributed to their reporting source and period.
Ask for the terms supplied with your own purchase: products and cover change. This comparison does not independently audit financial health, rank safety or measure UK claim-handling performance.