State of Health (SOH) tells you how much of the original battery capacity remains. Here's how to use it. Reading the report: SOH is usually shown as a percentage of original capacity. A car at 90% SOH retains roughly 90% of its original range. Also check for cell imbalance (voltage spread between modules)—a low SOH with balanced cells is often fine, but high imbalance causes sudden range drops and charging problems. Acceptable thresholds: for a car under 3 years old, expect 90%+ SOH. For 3-5 years, 85-90% is normal. Below 80% SOH, the battery may soon need replacement—replacement costs can exceed the car's value, so negotiate hard or walk away. How to verify: don't trust a screenshot. Ask for a live screen recording of the diagnostic app (like the brand's official tool) starting from the car's VIN page. Cross-check the fast-charging curve: a healthy battery charges at near-peak rate up to 60-70%; a degraded one tapers early. Finally, remember that hot climates degrade batteries faster—if the car spent its life in southern China, scrutinize SOH more carefully.

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 use an internationally certified electronic signature platform (such as DocuSign or Adobe Sign). Each signed contract generates a digital certificate with a timestamp and encrypted hash value, which has full legal defense effectiveness in international arbitration courts.