8.7. The RESS must prevent the build-up of an ignitable gas / air or dust / air concentration inside the compartment by means of a burst valve or vent tube, positioned away from the Driver. Any vent tube if fitted must discharge direct to atmosphere external to the Passenger compartment or survival cell.
8.8. All HV connections to the RESS must be made using either proprietary HV connectors with High Voltage Interlock Circuitry( HViL) or the cables must pass through HV rated cable glands of suitable size to match the cable and which preserve the IP rating of the external enclosure.
8.9. The enclosure containing the modules must also contain the BMS voltage and temperature sensing elements associated with the modules, service switch, fuses / circuit breakers and contactors.
9. Modules
9.1. Off-the-shelf commercially available or repurposed production modules must be used to make RESS packs. It is prohibited to assemble RESS modules or packs from individual cells.
9.2. It is prohibited to modify the modules in any way.
9.3. The Competitor must supply documents from the module producer specifying safety relevant data, including manufacturers’ datasheet: UN38.3 report and Material Safety Data Sheet( MSDS). Including RESS characteristic diagram showing the limits of voltage( U), power( W), temperature( T) and State of Charge( SoC). These documents must be provided to ASN 3 months prior to the Vehicle inspection. Equivalent data from a 3rd party test house may be submitted in place of manufacturers data. Evidence of test house capability must be included as part of the submission.
10. Battery Management System 10.1. A Battery Management System( BMS) from an approved supplier is mandatory. 10.2. For Modified EVs the architecture of and functionality of the BMS must not be changed from standard.
10.3. The BMS must ensure that all cells do not exceed the manufacturers stated limitations for voltage, current and temperature under any circumstances.
10.4. The BMS in all cases must monitor every serial cell for voltage and a minimum number of cells( evenly distributed throughout the modules / pack) for temperature in order that the hottest, coldest and average cell temperatures are monitored. Full details of the temperature monitoring must be provided to ASN 3 months prior to the Vehicle inspection.
10.5. In the event that any cell exceeds the manufacturers stated limitations for voltage and / or temperature, within 2 seconds the BMS must reduce power to less than 5kW in order to leave the course or automatically isolate the RESS from the traction circuit if it is not safe to reduce power.
11. Cooling 11.1. If the RESS is liquid cooled, > 51 % water-based coolant must be used. 11.2. The cooling liquid must not come into direct contact with any active components within the RESS.
12. Electrical Equipment and General Electrical Safety 12.1. Specifications for general electrical safety are laid down in Appendix J – Article 253-18.1.
12.2. Specifications for the Power electronics( inverters, DC / DC converters, on-board charger etc.) are laid down in Appendix J – Article 253-18.5.
12.3. Any Vehicle with an electrical system operating at a voltage exceeding 60V DC or 30V AC must display the label detailed in App. 13 Diagram 6 next to all Competition Numbers. Label minimum size 75mm x 75mm x 75mm.
12.4. In cases where the voltage of the Power Circuit belongs to voltage class B( 2.9), symbols warning of“ High Voltage” must be displayed on or near the protective covers of all electrical equipment that may operate at high voltage( App. 13 Diagram 6). The symbol background must be yellow, and the bordering and the
Motorsport UK 2025 National Competition Rules Version 11
Chapter 7 Appendix 11- Electrified Vehicles 284