Skip to content
BattGrade
All readable models
Battery health check

BMW i3 battery health check

How to read the high voltage battery of the BMW i3 with the BattGrade app: the adapter for your phone, where the port is, how the test runs and what the certificate shows.

Get early access See a sample certificate
What you need

The adapter for your phone

Any one of these Bluetooth OBD2 adapters reads the BMW i3. Choose one that works with your phone.

AdapterWorks with
OBDLink MX+Android · iPhone support coming
OBDLink CXiPhone and Android

We recommend the STN adapters listed here. Cheap ELM327 clones have not been tried on these cars.

Compare all adapters
Port location
Under the steering wheel
Cable
None, standard OBD2 port
The test

How the test runs on the BMW i3

A few minutes with the car switched on. The app only reads data: nothing is written to the car.

Before you start

Switch the car on before you plug in the adapter. On these cars, diagnostic traffic while the car is locked can set off the alarm.

  1. 01

    Wake the car

    The car must be awake, with the ignition on or in READY mode depending on the model. A sleeping car returns no battery data.

  2. 02

    Plug in and pair

    Plug the adapter into the OBD2 port and pair it with the BattGrade app over Bluetooth.

  3. 03

    Read the battery

    The app identifies the car from its VIN and reads the battery management system with read-only requests. Every request and response is kept with the test as raw data.

  4. 04

    Get the result

    BattGrade's server recomputes the result from the raw data, and the certificate is issued from the server's result, signed, with a QR code anyone can check.

State of Health

How the SoH of the BMW i3 is measured

The app can use these methods on the BMW i3, in order of preference. The certificate names the method used and gives an uncertainty band in points either side of the score.

  1. 1

    BMS-reported

    First choice

    The SoH value reported by the battery management system, used as it is.

Validation

Where validation stands

Validation in progress

The app reads the BMW i3 today, and validation on real cars is in progress. This page will show when it is complete.

Either way, BattGrade's server recomputes every result from the raw data read from the car, and each certificate names its method and uncertainty band.

Read the methodology
The certificate

What the certificate shows

A certificate for the BMW i3 carries the same fields as the sample, filled in with the car's own data.

  • The State of Health (SoH), with the method behind it and an uncertainty band
  • A grade from A to F, on the same bands for every make
  • Warning signs, wherever the car provides the data
  • The name of the inspector who ran the test
  • Valid for 6 months from the day it is issued
See a sample certificate Download a sample certificate (PDF)
Read the methodology

Related models

Other BMW i3 / Mini Cooper SE cars the app reads today.

See all readable models

Questions about the BMW i3

Any one of these: OBDLink MX+ or OBDLink CX. On iPhone, use OBDLink CX.
Under the steering wheel. No extra cable is needed: the adapter plugs straight into the standard OBD2 port.
The app can use these methods, in order of preference: BMS-reported. The certificate names the method used and gives an uncertainty band.
Yes. The app reads the BMW i3 today, and validation on real cars is in progress.
A few minutes, with the car switched on. The app only reads data and writes nothing to the car.

Test BMW i3 batteries with BattGrade.

The Android app is in testing and the iPhone version comes next. Join early access and we will get you started.

Get early access See all readable models