E-Ink display allowing me a quick glance of free battery space in my two BEVs and my Home Battery. As I have only have one wallbox/charger for two cars, this allows me to decide quickly how much energy to still expect today from my PV and which car to charge.
evcc controls a KEBA wallbox and manages charging of a Mini and a Volvo. Home Assistant aggregates vehicle data, home battery state and PV forecast into a single source of truth.
The project ships two variants of the same dashboard concept:
| Variant | File | Description |
|---|---|---|
| E-Ink display | carport_display.yaml |
ESPHome config for a Waveshare 7.5" display mounted at the carport entrance. Refreshes every few minutes, readable at 3 m distance. |
| Lovelace card | lovelace_card.yaml |
Home Assistant custom:button-card mirroring the same layout at 75% scale with live sensor data. Requires button-card via HACS. |
Both variants share identical data sources, layout structure, and business logic (EVCC sensor priority, fallback to native vehicle APIs, active-vehicle highlighting).
In my set-up the two cars are parked side by side, with chargeports being not even a meter apart. So unplugging one and plugging the other goes to quick for evcc to notice the change. I have reduced the evcc cycle to 15 seconds and wait a bit each time. This pause seems to be the only way to terminate a charging session for the evcc history and start a new one. Also the Mini seems not to support vehicle detection in evcc, so I do need to change to the Mini manually, as I care about propper charging history in evcc for each vehicle.
BMW CarData / Volvo API ──► Home Assistant
evcc (KEBA wallbox) ──────► Home Assistant ──► Lovelace card / ESPHome (ESP32) ──► E-Ink Display
Victron / Solcast PV ─────► Home Assistant
| Component | Model | Link | Note |
|---|---|---|---|
| Display | Waveshare 7.5" V2 (800×480 px, B/W) — 075BN-T7-D2 |
Waveshare 800×480, 7.5inch E-Ink display HAT for Raspberry Pi | no Raspi needed, despite the name |
| Controller | Waveshare ESP32 Driver Board | Waveshare ESP32 Driver Board | |
| Firmware | ESPHome, Arduino framework | ||
| Power | USB-C, mains-powered (permanent) | ||
| Case | 3D printed | Waveshare 7.5inch e-paper display case | modded that quite a bit to fit my purpose |
Per vehicle (top ¾)
- Thick border around the vehicle currently connected to the wallbox
- Range in km — the dominant figure
- SOC % and free capacity (kWh)
- Energy charged this session (kWh) — shown for connected vehicle
Home energy (bottom ¼)
- Home battery: SOC % and free capacity (kWh)
- PV forecast: remaining yield today (kWh)
- Footer (E-Ink only): firmware version, refresh interval, last refresh timestamp
| Value | Primary source | Fallback |
|---|---|---|
| Vehicle SOC / range | sensor.evcc_carport_vehicle_soc / _range |
BMW CarData / Volvo API |
| Session energy | sensor.evcc_carport_charged_energy |
— |
| Active vehicle | select.evcc_carport_vehicle_name |
— |
| Home battery | sensor.battery_percent |
— |
| PV forecast | sensor.verbleibende_pv_produktion |
— |
evcc sensors are preferred when a vehicle is connected as they update more reliably during charging. The native vehicle API sensors serve as fallback when no vehicle is at the wallbox.
| File | Purpose |
|---|---|
carport_display.yaml |
ESPHome device configuration for the E-Ink display |
lovelace_card.yaml |
HA Lovelace custom:button-card definition |
logo_mini_inv.png |
MINI wordmark, 1-bit inverted, 72×31 px |
logo_volvo_inv.png |
Volvo wordmark, 1-bit inverted, 110×15 px |
logo_evcc_inv.png |
evcc logo, 1-bit inverted, 80×22 px |
Logo PNGs must be placed in /config/esphome/ alongside carport_display.yaml.
- Copy
carport_display.yamland the three logo PNGs to/config/esphome/ - In the ESPHome UI: New Device → adopt the ESP32 board
- Replace the generated YAML with
carport_display.yaml - Adjust
wifi_ssid/wifi_passwordinsecrets.yaml - Run Clean Build Files, then Install → Wirelessly
The display registers a number entity Display Refresh Interval (0.03–60 min, step 0.01) in Home Assistant. Changing the value triggers an immediate refresh without reflashing.
ESPHome model: 7.50inv2p — required for full_update_every.
Busy pin: GPIO25, inverted: true.
Note: After updating logo PNG files always run Clean Build Files before installing to avoid stale image cache.
- Install button-card via HACS
- In your HA dashboard: Edit → Add Card → Manual
- Paste the contents of
lovelace_card.yaml
No additional dependencies. Logos are embedded as Base64 data URIs directly in the YAML.
The Lovelace card mirrors the E-Ink layout at 75% scale and updates live with every HA state change:
- Same two-column vehicle layout with brand logos
- Same bottom row for home battery and PV forecast
- Active vehicle highlighted with a thick border