Home › Guides › BMW i3 battery check
How to check a used BMW i3 battery before you buy (UK)
Published · Last updated · based on 9 sourced i3 data points and 15 sources
The BMW i3 was built with three battery sizes, many used i3s are now outside BMW's battery warranty, and the car's own capacity reading can flatter the battery. This guide covers how to tell the batteries apart, read the hidden capacity menu, check the warranty and the battery recall, and compare a result with tested cars.
All i3 figures with method and date: used BMW i3 battery data. Going to a viewing? Make a printable list of questions for the seller.
1. Identify the battery: 60, 94 or 120 Ah
| Battery | Built (EV Database) | Usable / gross when new | Chemistry | Source |
|---|---|---|---|---|
| 60 Ah ("22 kWh") | Sep 2013 – Feb 2017 | 18.8 / 21.6 kWh | NMC333 | EV Database |
| 94 Ah ("33 kWh") | to Oct 2018 | 27.2 / 33.2 kWh | NMC333 | EV Database |
| 120 Ah ("42 kWh") | Nov 2018 – Jul 2022 | 37.9 / 42.2 kWh | NMC622 | EV Database |
Dates are EV Database listings, checked 2026-10-27. EV Database lists CCS rapid charging as an option on the 60 Ah car, so check a 60 Ah car has it if you need rapid charging.
All three have 96 cells, and the bigger batteries use bigger cells, so the Ah figure tells you what range to expect. Make sure any "battery health" figure is compared against the right battery size.
2. Check the battery warranty – many i3s are now outside it
BMW UK: high-voltage battery covered against material defects or excessive loss of capacity for up to 8 years from first registration or 100,000 miles, whichever comes first (BMW's page does not state a % threshold; check the warranty handbook). (BMW UK, checked 2026-10-20)
- The time limit has passed for any i3 first registered before October 2018. That covers 60 Ah cars and most 94 Ah cars. Check the first registration date on the V5C.
- For a car still inside the 8 years, our battery warranty checker works out the time and mileage left (UK terms: 8 years / 100,000 miles; "excessive loss of capacity" – % not stated on BMW's page).
- Outside warranty, a battery fault is your cost. See EV battery replacement cost in the UK before you agree a price.
3. Check the battery recall
DVSA's recall file lists one i3 battery recall, R/2022/322 (14 November 2022). It covers a manufacturing defect in the winding of the films inside battery cells, fixed by replacing the defective cell module. It lists 18 UK vehicles built between 12 November 2018 and 16 July 2021, which means 120 Ah cars (DVSA, downloaded 2026-10-27). Run the free GOV.UK recall check on the registration (GOV.UK). If a module was replaced, ask for the invoice.
4. Read the hidden capacity menu – then get a real test
The i3 shows its own capacity estimate in a hidden instrument-cluster menu. Item 13.08 "Batt. Kapa. max." is unlocked with the sum of the last five digits of the VIN (Praxis Elektroauto). Compare the kWh shown with the usable capacity when new in the table above. It's a BMS estimate that moves with temperature and cell balancing, so one reading is a rough guide only.
Independent tests show why that matters:
- A UK i3 120 Ah (42 kWh) at 50,078 miles: the car's own SoH said 96.0%, AVILOO measured 91.2% (Car360).
- A UK i3 120 Ah (42 kWh) at 61,122 miles: the car's own SoH said 94.0%, AVILOO measured 90.0% (Car360).
- It can go the other way. On a 60 Ah car at 175,000 km, a drive-down test gave 85.6% while the car's own figure showed 84% (Bjørn Nyland).
AVILOO works out SoH with its own algorithms rather than copying the car's reading (AVILOO GmbH). For an older i3 outside warranty, an independent test is the best protection you can buy. Prices are on our buying guide, and how to read a battery health certificate explains each field.
5. Compare the result with what's normal
| Group | Mileage / age | SoH | Sample | Source (date) |
|---|---|---|---|---|
| i3 120 Ah | >100,000 km ≈ 62,137 mi | 93.8% | multi-car average of cars above 100,000 km | Carla AB (2026-07-08) |
| i3 120 Ah (42 kWh), UK car | 80,593 km ≈ 50,078 mi | 91.2% | n=1 | Car360 (2026-02-11) Single car (n=1). Published mileage 50,078 miles. Car's own BMS SoH on the same certificate: 96%. |
| i3 120 Ah (42 kWh), UK car (another) | 98,366 km ≈ 61,122 mi | 90.0% | n=1 | Car360 (2026-04-01) Single car (n=1). Published mileage 61,122 miles. Car's own BMS SoH on the same certificate: 94%. |
| 2014 BMW i3 22 kWh | 103,000 km ≈ 64,001 mi | 89.4% | n=1 | Bjørn Nyland / TB Test Results (rows dated 2019-01-15 to 2026-10-14 (each row has its own test date)) Single car (n=1), Bjørn Nyland test 2020-02-29: 16.8 kWh usable vs 18.8 kWh new. |
| 2017 BMW i3 33 kWh | 138,000 km ≈ 85,749 mi | 94.1% | n=1 | Bjørn Nyland / TB Test Results (rows dated 2019-01-15 to 2026-10-14 (each row has its own test date)) Single car (n=1), Bjørn Nyland test 2024-06-02: 28.5 kWh usable vs 30.3 kWh new. |
| 2019 BMW i3 42 kWh | 152,000 km ≈ 94,448 mi | 98.4% | n=1 | Bjørn Nyland / TB Test Results (rows dated 2019-01-15 to 2026-10-14 (each row has its own test date)) Single car (n=1), Bjørn Nyland test 2023-11-25: 37.4 kWh usable vs 38 kWh new. |
| i3 60 Ah / 22 kWh (2016) | 175,000 km ≈ 108,740 mi | 85.6% | n=1 | Bjørn Nyland (undated on page) 16.1 kWh usable vs 18.8 kWh new (calculated 85.6%); car BMS showed 84%. |
| All US versions grouped | after 3 years | 92% of range | multi-car range kept, not SoH (US) | Recurrent (current page) |
| All US versions grouped | after 5 years | 89% of range | multi-car range kept, not SoH (US) | Recurrent (current page) |
Single cars (n=1) are examples, not averages. Bjørn Nyland's tests compare measured usable capacity with his own reference for each battery when new, which can differ slightly from EV Database's figures. Recurrent figures measure range, not capacity, for US cars. Every row is also on the i3 data page.
- The i3 is a popular used city EV. Carla's Swedish data puts the 120 Ah version 6th of 20 for battery health after >100,000 km (93.77%). (Carla AB)
- As a rule of thumb for all EVs, ADAC expects at least 92% at 50,000 km, 88% at 100,000 km, 84% at 150,000 km, 80% at 200,000 km (ADAC).
- For a quick estimate at a given mileage, use the battery health estimator.
Also see: general used-EV battery checklist · questions to ask an i3 seller (printable) · EV battery replacement cost (UK) · Nissan Leaf battery check · Renault Zoe battery check · all models compared.
Sources used on this page
15 sources · 9 data points: 6 from non-AVILOO methods, 3 measured with AVILOO tests.
- Large test datasets (1 source, 1 data point): Carla AB
- Connected-car / telematics (1 source, 2 data points): Recurrent
- Single-car tests (4 sources, 6 data points): Car360, [2], Bjørn Nyland, Bjørn Nyland / TB Test Results
- Manufacturer (1 source): BMW UK
- Other (specs, guides, news, surveys) (8 sources): EV Database, [2], [3], DVSA, GOV.UK, Praxis Elektroauto, AVILOO GmbH, ADAC
Owner-reported and listing values are single cars (n=1) read from the car, an app or an OBD tool – useful examples, not averages. Range-retention figures (Recurrent) measure range, not capacity. Full details: methodology & all sources.
We are not paid by the battery-test providers mentioned on this page. Links marked "paid link" in the "Useful products and services" box are affiliate links. See our disclosure.
Get this specific car tested
We are not paid by these test providers. How we make money.
Model averages can't tell you about the car in front of you. An independent battery test (typically a short OBD plug-in test, some remote) gives an SoH figure and often a certificate you can use when negotiating.
- AVILOO – Independent OBD-based battery test (FLASH / Premium) with certificate; available via partners in the UK and EU.
- Generational – UK OBD plug-in test with certificate (SoH, range, remaining warranty, cell balance); sold through dealers and independent mobile testers.
- Moba – Postal OBD kit: you run the test yourself and post the box back for a digital battery certificate (Europe – check vehicle support and delivery country).
Prices change – check the provider's site. Provider names are used for identification only.
Useful products and services
- Charging cable: check that the car comes with its charging cable(s) at the viewing. If one is missing, replacements are sold separately: i3 charging cables at EV King paid link.
- Tyres: check tread depth and wear at the viewing. To price replacements, search by the size printed on the tyre wall: car tyres at Tyres UK paid link.
- Parts and tools: wiper blades, bulbs, 12V batteries and tools for the car you buy: GSF Car Parts paid link (UK).
Some links are paid links: we may earn a small commission at no extra cost to you. This never changes the battery data we show (disclosure).
FAQ
Which BMW i3 battery do I have – 60 Ah, 94 Ah or 120 Ah?
Age is the first clue. EV Database lists the 60 Ah (18.8 kWh usable) from September 2013 to February 2017, the 94 Ah (27.2 kWh usable) up to October 2018, and the 120 Ah (37.9 kWh usable) from November 2018 to July 2022. Confirm it from the advert, the paperwork or a BMW dealer, because range differs a lot between them.
Is a used BMW i3 battery still under warranty?
BMW UK covers the high-voltage battery for up to 8 years from first registration or 100,000 miles, whichever comes first, against defects or "excessive loss of capacity" without stating a %. So the time limit has passed for any i3 first registered before October 2018.
Was there a BMW i3 battery recall in the UK?
Yes. DVSA recall R/2022/322 (November 2022) covers a manufacturing defect in battery cells, fixed by replacing the faulty cell module. It lists 18 UK vehicles built between 12 November 2018 and 16 July 2021. Run the GOV.UK recall check on the registration to see if it is outstanding.
Is the i3 hidden menu battery capacity reading accurate?
It is the car’s own estimate (item 13.08 “Batt. Kapa. max.”) and it moves with temperature and cell balancing. On two UK AVILOO certificates for 120 Ah cars, the car’s own SoH was 4–5 points higher than AVILOO’s. Use it as a rough guide and get an independent test for the real figure.
Get alerts for the BMW i3
We email (from alerts@usedevbatteryhealth.com) when new battery data is added for this model. Low volume, no spam, unsubscribe any time. We'll first send a confirmation email – you're only subscribed once you click the link in it.
Emails are sent via MailerLite (EU). We never share your address. Every email has an unsubscribe link.
Own a BMW i3? Share your battery health
Every owner report makes this data more useful. It takes 2 minutes. Add your car's data