UL94V-0 is a plastic material's flame rating, so it belongs to the connector housing rather than to the entire battery pack system.

If you have ever compared battery pack connectors, you have probably seen a line like "thermoplastic housing, UL94V-0." It sits next to the model number, and it sounds serious. Many readers assume it means the whole connector, or even the whole battery pack, has passed a fire-safety certification. That is an easy mistake. UL94V-0 describes how a plastic sample behaves when exposed to a small flame test. It is a property of the housing material. Thermoplastic is a moldable polymer used to create the connector body, hold the contacts, and provide electrical insulation. Understanding what UL94V-0 covers helps you compare connector materials without stretching the claim beyond the plastic housing.