Lithium Integration (Smart Parking)
The Lithium integration turns parking lots into smart environments: it monitors vehicle entries and exits in real time and automatically updates the number of available spots. The occupancy calculated by ACCELERO is published to the Lithium devices (for example, spot panels), offering a modern experience connected to access control.
This integration is provided as a plugin (lithium) and must be installed and enabled by the IONGRADE technical team. Contact support to check compatibility with your ACCELERO version.
Current plugin version: 0.0.1 — compatible with ACCELERO 2.16.5, 2.16.6, 2.16.7, or 2.16.8.
What the integration does
With the plugin active, ACCELERO starts publishing the occupancy of the monitored parking areas to the Lithium devices. Communication happens over MQTT: ACCELERO calculates the occupancy from its own vehicle access events and sends the status to the devices, which can also request the current occupancy on demand.
| Feature | What happens in ACCELERO |
|---|---|
| Occupancy monitoring | On each vehicle movement in a monitored parking area, the occupancy is recalculated and published to the Lithium devices |
| On-demand publishing | When a device requests the current occupancy, ACCELERO responds with the status of used and total spots of each configured area |
| Device registry | A dedicated screen to manage the Lithium devices (description, serial, status) |
| Device keep-alive | Periodic messages sent by the devices update the metadata of each piece of equipment (last contact/state) |
The spot count is maintained automatically by ACCELERO's access control — with no manual operation and no additional counting sensors.
Configuration
Navigation path: Settings > Integrations - Lithium
The screen has one tab: General.
The Settings > Integrations - Lithium configuration screen, General tab, showing the Integration data section with the Parking areas field.
General tab — Integration data
| Field | Description |
|---|---|
| Parking areas | Multi-selection of ACCELERO areas. Only the selected areas have their occupancy monitored and published to the Lithium devices |
Movements in areas that are not in Parking areas do not generate occupancy publishing. Select all areas whose spots should be displayed by the devices.
Screen buttons
| Button | Function |
|---|---|
| Save | Persists the configuration |
| Back | Returns without saving |
Lithium Devices
Navigation path: Settings > Lithium
Lists the registered Lithium devices and allows creating, editing, and deleting them.
Device list in Settings > Lithium, showing the Description, Serial, Metadata, Status, and Actions columns, plus the New device button.
List columns
| Column | Content |
|---|---|
| Description | Device name |
| Serial | Device serial number |
| Metadata | Technical device data, updated automatically (e.g., keep-alive) |
| Status | Indicates whether the device is active |
| Actions | Edit the device |
Device registration / editing
Registration can be done by inline addition in the list itself (the New device button) or by the edit screen.
Lithium device registration/edit form with the Description, Serial, and the Status selector.
| Field | Description |
|---|---|
| Description | Device name (3 to 50 characters, required) |
| Serial | Device serial number (3 to 50 characters, required). Used to identify the equipment in the MQTT messages |
| Status | Activates or deactivates the device |
The Serial is the key that links the messages sent by the device to its registration in ACCELERO. If the serial does not match any registered device, the received messages are ignored.
Bulk deletion
The list allows selecting several devices and deleting them at once via the Delete action in the More actions menu.
How occupancy is published
The integration works over the MQTT channel. ACCELERO calculates the occupancy of each monitored parking area and publishes a status in the format:
| Data | Content |
|---|---|
| area | Area identifier |
| used | Number of vehicles currently in the area (current occupancy) |
| total | Total vehicle capacity of the area |
Publishing happens at two moments:
- Update on movement — when a vehicle enters or leaves a monitored area (or a monitored origin area), ACCELERO recalculates and publishes the occupancy automatically.
- Response to a request — when a Lithium device requests the current occupancy, ACCELERO publishes the status of all configured areas.
Occupancy considers the movement of vehicles. The total capacity of each area comes from the configuration of the area itself in ACCELERO.
Diagram of the MQTT flow between the Lithium devices and ACCELERO: vehicle movement → occupancy recalculation → status publishing; and occupancy request → status response.
Use cases
Enable smart parking
- Request that IONGRADE install the
lithiumplugin. - In
Settings > Integrations - Lithium, select the Parking areas that should be monitored. - In
Settings > Lithium, register the devices with the correct Description and Serial and keep them active. - Make sure the selected areas have the vehicle capacity configured.
- Move a test vehicle and confirm that the published occupancy reflects the entry/exit.
Replace or restore a device
- Register the new device in
Settings > Lithiumwith the equipment's Serial. - Deactivate (Status) or delete the old device.
- Confirm that the keep-alive messages of the new equipment are updating the Metadata column.
Best practices
- Areas dedicated to parking: select only areas that represent real parking lots to avoid irrelevant occupancy publishing.
- Correct capacity: keep the total vehicle capacity of the areas updated — it is the basis of the available-spots calculation.
- Reliable serial: register the serial exactly as recorded on the equipment; discrepancies make ACCELERO ignore the device's messages.
- Status as a maintenance control: deactivate devices under maintenance instead of deleting them, preserving the metadata history.
Troubleshooting
The devices do not update the spots
Possible causes:
- The area is not checked in Parking areas.
- The area's vehicle capacity is not configured.
- The device is inactive (Status off).
Solution:
- In
Settings > Integrations - Lithium, confirm that the area is selected. - Check the area's vehicle capacity.
- In
Settings > Lithium, confirm that the device is active.
The device's messages are ignored
Possible causes:
- The Serial provided in the registration does not match the equipment's serial.
- The device is not registered.
Solution:
- Check the serial recorded on the equipment and compare it with the registration in
Settings > Lithium. - Register the device if it does not yet exist.
The MQTT communication (occupancy publishing, keep-alive, and requests) depends on the ACCELERO messaging infrastructure. In case of a persistent failure, contact IONGRADE support to validate the environment.
Integration with other modules
Areas
Occupancy is calculated per Area: only areas checked in Parking areas are monitored, and the area's vehicle capacity defines the total number of spots.
Vehicles and parking spots
The occupancy count reflects the movement of Vehicles. Also see Parking Spots to understand spot control in ACCELERO.
Controllers and channels
The movement that triggers the occupancy recalculation comes from the access events recorded by the Controllers in the configured areas.
Next Steps
- Areas — Configure the parking areas and their capacities
- Vehicles — Understand the vehicle registry used in the count
- Parking Spots — Learn how ACCELERO controls vehicle spots
- Controllers — See how access movements are recorded
- Plugins — Learn more about the ACCELERO plugin system