The HV Definitions & Glossary is an A to Z extension to our website that just gives you an alternative way of finding information.
Battery Disconnect Unit – contains the contactors, fuses, pre-charge circuit and current sensors. This unit sits inside/on top of the battery pack and has all of the components for monitoring, activating, and deactivating the high-voltage battery system.
Busbars are the main electrical connections between cells, modules and connect all of the HV system to the outlet connector. Normally made from copper or aluminium.
Clearance – the line-of-sight distance between two conductors through the air.
Charge Voltage – voltage that the battery is charged to when charged to full capacity.
Contactor – a switch that can be operated by the control system. They are essentially a relay.
Creepage – the distance between two conductors on the surfaces of the parts or along the surface of the insulating material.
Current Sensor – can include resistive or magnetic elements based on their structure. We use these elements for sensing the current to be measured.
Cut-off Voltage – the minimum allowable cell voltage defines this lower voltage limit.
Fuse – device that protects electrical circuits against undesired high currents. We can use passive fuses and pyro fuses in battery design.
HV – abbreviation of High Voltage and in automotive world this means above 60V DC.
HVIL – Hazardous Voltage Interlock Loop.
Isolation Resistance of a Pack – for the complete HV system to ground with the contactors closed should be >500Ω/V and hence for a battery pack its resistance target must be specified by the HV System designer, typically >1,500kΩ.
LV – abbreviation of Low Voltage and in automotive world this means below 60V DC.
Nominal Voltage – reference voltage of the battery at 50% state of charge and at the defined discharge rate.
Pre-Charge Resistor – when the battery pack contactors are closed onto a motor and inverter there will be an inrush of current into the inverter capacitor. This very high current is at a minimum likely to age the contactors, it could permanently damage the contactors.
Pyro Fuse – a fuse that can be blown by a signal.