Help

Questions, bug reports and captures go to the address below. I read every message myself — MultiVolt is a one-person project.

Contact

[email protected]

Usually answered within a few days. German and English.

A battery is being read incorrectly?

That is the single most useful report there is. Helpful details: manufacturer and model of the battery, the name it shows up under in the Bluetooth list, which protocol the app detected, and which number is wrong — along with the value the manufacturer app shows in the same place.

Frequently asked

Where do I find demo mode?: Settings → Data source → Demo. Three simulated batteries with real LiFePO4 physics then run. On the very first launch, demo mode is already on.
Which batteries are supported?: Any with a BMS speaking Ective, JBD/Xiaoxiang or Daly. That covers a large share of LiFePO4 house batteries with Bluetooth, including many brands that sell the same electronics under their own name.
Why does Android ask for my location?: On Android 11 and earlier, Google tied Bluetooth scanning to the location permission, because a location can in theory be inferred from radio signals. MultiVolt does not do that. From Android 12 the app asks only for "Nearby devices" and is explicitly flagged as not being used for location.
Will the app warn me when it is closed?: No. Warnings appear while the app is running. Background operation and notifications are not built. For protecting your batteries, rely on the BMS, not on a phone.
How many batteries at once?: Six. That is also the technical ceiling of the Bluetooth layer, not just a limit of the subscription.
Does it work on an iPad?: Yes, and the layout uses the width: on an iPad two or three battery tiles sit side by side. Bluetooth needs an iPad model with BLE, which in practice means any current one.
Can the app switch off my battery or change its settings?: No, and that is a deliberate boundary. MultiVolt sends read requests only. To Ective batteries it sends nothing at all.
Is any of my data transmitted anywhere?: No. The app contains not a single network call. The only outside connection is the purchase, handled by the App Store or Google Play.
How do I cancel the subscription?: In the settings of your App Store or Google Play account, at the latest 24 hours before the current period ends. Inside the app, the purchase screen takes you straight there via "Manage subscription".

The app interface is currently in German only. This website is available in several languages; the app itself is not yet.