The powertrain of the new eCitaro bus is based on the existing electric ZF AVE 130 axle with electric motors at the wheel hubs. The peak output of the motors is 2 x 125 kW, while the torque is 2 x 485 Nm.
The design uses modular lithium-ion batteries with a total capacity of 243 kWh, split between up to ten modules each supplying around 25 kWh. As well as two battery modules on the vehicle roof, the standard equipment includes four modules in the rear of the bus, replacing the combustion engine and transmission. Another two or four battery modules are mounted on the roof of the bus.
Each battery module is made up of 15 cell modules as well as a control unit for monitoring purposes and as a means of balancing the charge of the battery cells. Each cell module houses twelve prismatic 37 Ah cells. The modular architecture allows operators to choose range or reduce weight and allow more space for passengers, but with more charging time.
With the maximum ten battery modules, the eCitaro can carry around 88 passengers and will be launched in September.
For the start of series production, the bus is using plug-in charging with a Combo-2-plug. A roof top pantograph for en-route charging is planned.
Solid-state lithium ion batteries are also under development for the bus, providing a longer service life and a capacity of 400 kWh. This will allow the bus to be used for 70 percent of all urban journeys without needed to recharge.