It looks like a simple grey metal box, but the battery pack we’ve integrated into our EVolution Class locomotive hides a very carefully designed complete energy storage and management system. 

The heart of the system is of course our battery itself, which is made up of many individual NCM712 Lithium Ion cells. Employing that particular chemistry has enabled us to achieve an impressive energy density of 265 Wh/kg, which ultimately translates to 55Kw of energy stored in a box that weighs just 320Kgs!

The pack also contains a fully Integrated cell management system monitoring and controlling a constant flow of liquid through a built in cooling matrix. In practice the energy delivery rates in our locomotive prompt only a 10 degree temperature rise above the ambient, so the coolant operates more to maintain a constant and efficient working battery temperature than it does to remove heat. 

There’s also a built in contactor control system monitoring all the cables and connectors throughout the locomotive’s power train. If a single plug or connection is lost, power is automatically isolated centrally within the box, making the system fail safe, and the whole unit is further protected with an externally accessible service disconnect fuse that can be removed prior to any service operations.

There’s also a high voltage pre-charge circuit, a CCS charge control module and numerous other fancy devices with anagrams for names, but they are all in a neat grey box so that you don’t have to think about them. 

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