EV & Hybrid High-Voltage Battery Diagnostics and SOH Reporting in 2025

How to sell high-voltage battery health checks to EV customers

As the EV parc grows, buyers and fleet managers want to know the real condition of the high-voltage battery before they pay. This created a new niche: independent workshops that can produce a reliable State of Health (SOH) report using aftermarket tools and OEM data. Solutions like AVILOO and advanced EV scanners make this realistic even for smaller shops.

1. What SOH actually means

SOH is the remaining usable capacity vs. the original design capacity. A 90% SOH battery is considered healthy; below 80% many OEMs recommend repair or module intervention.

2. Tools available to independents

• EV-capable diagnostic tablets (Autel Ultra EV, MS909/919 with HV kit, Launch EV): read battery data, isolation, temperature and let you follow OEM-level test plans.
• External SOH testers like AVILOO: connect to OBD, drive or charge, and get a certificate that can be shown to the customer or dealer.
• Bench/HV testers (MSG, MS800/801): for deeper battery work, balancing and module replacement.

3. Typical use cases in 2025

1. Pre-purchase EV inspection: customer wants to know SOH and weak modules before buying a used EV.
2. Warranty/insurance confirmation: provide independent proof of battery condition.
3. Service upsell: detect imbalance/overheating and offer cell/module repair.

4. How to package and sell the service

• Basic OBD read + short report → low price, 30–40 mins
• Full drive/charge test with certificate → 1.5–2 hours
• Fleet/ride-hailing periodic battery checks → subscription model

5. Safety & training

High-voltage work requires PPE, insulated tools, and lockout/tagout procedures. Make sure your staff is HV-certified before opening packs. Many aftermarket scanners now display step-by-step connection graphics to reduce risk.

Conclusion

By adding HV battery diagnostics, an independent workshop can keep EV customers in-house and create a premium, data-driven service. The hardware is already on the market and prices are dropping; what matters is having a clear report template and a safe workflow.