Obtaining precise internal resistance at different SOC levels requires disassembling the battery pack and connecting it to a professional charge-discharge cabinet for several days of cycling tests. This is beyond the scope of non-destructive used car inspections; we only provide real-time estimated internal resistance data based on OBD port readings.

We maintain an absolute skeptical attitude. In addition to regular visual inspections, we focus on checking for sediment accumulation around the sunroof drainage channels and look for water stains under the A-pillar trim and front floor mats. This is the only effective physical evidence to determine if the sunroof drainage holes are blocked, leading to hidden leaks.

For older vehicles or those used in high temperature and humidity areas, we will focus on opening the hood to check if the insulation of the wiring harness in the high-temperature area of the engine compartment is cracked or brittle, to identify potential short circuit risks that could lead to spontaneous combustion.