Battery swapping stations for electric scooters

The FTC305 connects to the CAN interface of the battery management system (BMS). From there it gets everything the BMS knows about the battery: voltage, current, charge level, charging status, temperature, fault codes. Those data go to the server, and the owner of the network sees the condition of every battery wherever it happens to be: at a station, with a user or on the move.

That changes the technicians' work at once. Instead of a scheduled round of the stations they get a list of the batteries that genuinely need collecting: with a fault code, with falling capacity, overheating on charge. The rest carry on working.

The second feature is Manual CAN Commands. Up to 10 commands in the protocol of a particular BMS can be programmed into the FTx305 and sent remotely: once at power-up, again on demand, or periodically. If a battery is overheating, the server sends a command to shut it down. The user receives an SMS or an app notification asking them to stop and swap the battery at a station. That way an unpleasant incident can be stopped before it turns into a fire.

The third is data for warranty purposes. The tracker writes a usage history: what currents the battery was charged and discharged at, at what temperature, whether it went outside permitted modes. If a user claims the battery failed by itself, but it had been running in a prohibited mode for a week, the battery manufacturer (OEM) and the station network can show it. And the other way round: if the battery failed under normal use, that is visible too, and the dispute is settled fairly.

The fourth is protection against theft. Alongside the FTC305 an EYE Beacon Bluetooth beacon goes into the battery. The beacon has its own cell, good for years of operation. If a stolen battery is completely flat and the tracker inside it has switched off, the beacon carries on transmitting, and gateways hear it: stations, trackers in other scooters, staff smartphones. The battery can be found and recovered.

The same beacon helps with stock records. The system knows how many batteries are standing at each station, how many are on charge, how many are with users and how many are temporarily unavailable. Planning purchases and redistributing batteries between stations becomes easier. If by the evening one station has nothing but empty batteries left while full ones stand unused at the next one, that is visible on the map, and the service vehicle takes them to where demand is higher.

The equipment list for the use case also includes the TFT100 — Teltonika's tracker for the electric scooters and mopeds themselves. It goes on the vehicle if the network rents out not only batteries but the machines as well: then both the scooter and the battery in it are visible.

What is needed from the battery manufacturer. The CAN protocol of the particular BMS, a place inside the casing for the tracker and, if necessary, a way of bringing out antennas where the battery casing is metal. The tracker takes its power from the battery itself, so the charge level at which it goes into economy mode is set in advance. Coverage is checked separately wherever the batteries will stand: stations in underground car parks and enclosed spaces may send data with a delay. All of this is checked on a sample battery before a batch is bought.

Safe conditions for the command. Shutting a battery down while the scooter is moving would stop it in the middle of the road, so the command is configured in stages: first a warning to the user, with the shutdown coming after the scooter has stopped or on a confirmed dangerous overheat. Who can send the command manually is decided in advance, and every command stays in the battery's history.

An honest limitation: the arrangement works if the battery has a BMS with a CAN interface and the protocol is known. For cheap batteries with no digital interface, much of what is described here is not available.