Real battery SoH
Reads the state of health straight from the car’s BMS and logs it per trip — no third-party estimates.
DOC 07 Projects / MihariE · Android app · rev 2026.08
MihariE. The app that watches over the Honda e battery.
Battery state of health (SoH), the real degradation curve, per-trip consumption and 12 V auxiliary battery alerts — all via passive OBD/UDS reading, never writing to the car. 見張り means “to watch over”.
§ 01
What the app does
What real-time apps do not do: track the battery over time.
Generic OBD apps show the moment. MihariE builds the history — and the history is where an EV’s real health shows.
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Degradation curve
Builds the real degradation curve over months and years — the information that matters for resale and warranty.
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12 V battery watched
The auxiliary battery is the most common cause of a “dead” EV. MihariE measures resting voltage and warns when it runs low — before it fails.
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Automatic trip log
Detects every trip and logs distance, energy and efficiency (kWh/100 km) — with lifetime totals.
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100% passive
It only reads, never writes to the vehicle. The protocol was reverse-engineered and validated against the real dashboard, reading by reading.
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Exportable history
The full history can be exported as a password-encrypted file and restored on another phone.
§ 02
The app · real captures
FIG. 07-012026 · real captures
Boot screen · low-voltage alert on the 12 V battery · battery health (SoH) · trip log — the app in the real car.
§ 03
How it works
One OBD adapter, one phone, nothing else.
MihariE connects to the Honda e through a Bluetooth OBD adapter (for example, OBDLink MX+) and talks directly to the car’s ECUs over OBD/UDS. Much of this data is not documented by Honda — it took reverse engineering of the diagnostic protocol, with every reading validated against what the car’s dashboard shows.
The app reconnects on its own when the car is nearby, detects trips automatically and stores everything locally on the phone — your car’s data is yours, it never goes to any cloud.
- Vehicle
- Honda e
- Requirements
- Android + Bluetooth OBD adapter
- Reading
- 100% passive via OBD/UDS
- Data
- Stored locally · encrypted export
- Stack
- Kotlin · Android
- Status
- In daily use · Google Play under consideration
§ 04
Frequently asked questions
- What is it?
- An Android app that tracks the Honda e battery over time — SoH, degradation, consumption and the 12 V battery. The name comes from the Japanese 見張り (mihari), “to watch over”.
- Which cars?
- The Honda e. The protocol was reverse-engineered and validated against the car’s real dashboard.
- What do I need?
- An Android phone and a good Bluetooth OBD adapter (e.g. OBDLink MX+).
- Is it safe?
- Yes — 100% passive reading, the app never writes to the vehicle. Values are diagnostic estimates, not a Honda warranty test.
- Where do I download it?
- Not public yet. With enough interest, RFAS will publish it on Google Play at an accessible price; depending on uptake, an iOS version will follow.
Note · Register interest
Want MihariE on your Honda e?
If there is enough interest, RFAS will publish the app on Google Play at an accessible price — and, depending on uptake, an iOS version. Tell us you are interested: one line in the form is enough.