Fighting pollution in Mexico
With high levels of pollution in most of Mexican cities, zero emission vehicles are the only way to make a difference, according to industrial designer Alfonso Hernandez. Automotive industry is shifting toward electrification, but when this only concerns new vehicles, it can take decades to clear the air. That’s why Hernandez took it upon himself to help Mexico take the first big step to clean public transportation.
Converting old buses into all-electric vehicles
His company APV international is dedicated towards exploring the opportunities of renewable energy, by turning old combustion engine buses into all-electric vehicles, thereby reducing emission to zero and saving up to 80% in costs. As a proof of concept, Hernandez took on the challenge to convert a 13-year-old diesel-powered public transport bus.
Lithium-ion in stead of lead acid batteries
Ten months ago we received a phone call from Mexico. Hernandez and his team had managed to build complete their prototype and were testing it at the moment. They used a big lead acid battery bank to power the 250 kW electric motor from TM4. They knew this wasn’t the best solution, due to the large volume, high weight, short lifetime and poor performance. What they needed was a lithium-ion battery solution that could seamlessly be integrated in the test bus.
To be more precise: that meant 700 VDC voltage and a capacity of approximately 85 kWh. We provided an 84 kWh Lithium-Ion battery system with liquid cooling, consisting of 48 battery modules. Each has its own slave BMS and is connected to a MG Master HV 800V/600A that makes up the main BMS of the battery system.
On the one hand, the MG Master HV communicates with all battery modules and monitors their values. At the other side it communicates with the vehicle CAN-Bus, which consists of an advanced color display and the TM4 Neuro vehicle controller. We adjusted the CAN-Bus communication protocol to speak the same language as the TM4 Neuro. This makes the integration of the different systems even more simple.
We are proud to have contributed to developing Mexico’s first public service battery bus.
We challenged ourselves with the toughest goal, knowing that once achieved, any other project would be downhill. That’s why we developed our prototype with the strongest system we could think of. This opens roads for future markets like cargo transport in short range. This way we can start moving faster towards a cleaner transport solution where everybody wins.