E-mobility: Safe storage of traction batteries and lithium battery cells

Batteries weighing up to 700 kg and measuring 2,200 x 1,800 x 800 mm (W x D x H) are put in place via a double-leaf door on the grid-east level of the room system. An automatic door closing and hold-open system ensures door retention during loading and unloading. To close the door, the holding magnets are de-energised with a manual release button. In case of fire, the fire detection system in the room ensures automatic closing. The second, accessible section of the room is equipped with a single-leaf door and shelves for storing individual battery modules and cells. Lift truck-accessible, removable gratings serve as floor inserts.

Good visibility in both compartments is ensured by LED interior lighting. Further features include a 230 V socket and an Ethernet connection in each case.

The indoor climate is adjusted to the legal requirements for air quality and temperatures of 22°C +/-2K all year round. Excellent energy efficiency is ensured by the high insulation thickness of the fire protection panels (100 mm) and coordinated interaction of air conditioning, heating and technical ventilation via control technology. The air-conditioning system is a heat exchanger with CFC-free operating medium. An electric finned-tube heater serves as support heating for the air-conditioning system. A circulating air fan distributes the tempered air evenly in the rooms. The system is designed for 0.4-fold air exchange, which is realised by technical ventilation. Supply and exhaust air openings are weather-protected and secured by fire dampers.

All safety-relevant components of the room system are monitored and recorded by sensors and stored for 12 months. Supplementary information on running times and maintenance intervals create a holistic overview. The modern, user-friendly operating unit is connected to the high-performance controller via Modbus. The controller maintains its function even if the operating unit fails. The control software, developed by DENIOS, and its coordinated hardware components are designed specifically for each use case scenario. The mail server, included in the project scope of delivery, is controlled via modem and enables quick intervention in the event of a malfunction.

The room system has a semi-stationary water extinguishing system for which DENIOS has taken over the project planning, installation and documentation in accordance with VdS CEA 4001. By cooling the lithium storage medium as early as possible and for a sufficiently long time, thermal runaway can be prevented. If the reaction is already advanced, the cooling attack can prevent or stop a chain reaction.

The turnkey room system was created at the DENIOS production site in Bad Oeynhausen, Germany. This was followed immediately by transport, assembly and commissioning as well as customer staff training by the experienced and professional DENIOS experts. The lifting equipment and tools required for the process, the shoring material and the dowel technology for fastening to the subsoil were chosen to best serve the specific site use and environment by DENIOS. Only the on-site connections were made by the customer.

In addition to the new storage capacity, the customer is planning to add a test environment in the near future. Initially this will comprise a room system with test chambers and a room system with a measuring station. The DENIOS test rooms are perfectly suited for this.