Risk guide

How to read SOH and cell voltage delta

SOH reflects capacity-health trend; cell voltage delta reflects consistency risk. One number is not enough: review temperature, SOC, fault codes and test-drive behavior.

Job: viewing decision For: pre-purchase review Verify with diagnostics

Problem this solves

Buyers receive diagnostic reports but cannot interpret key readings, making them vulnerable to vague sales explanations.

Important boundary

This site only provides pre-purchase risk prompts. SOH, insulation, voltage delta, warranty and repair conclusions should be confirmed by manufacturer systems, professional reports, contracts and official explanations.

Onsite checks

Confirm whether data was read at rest, after charging or after a test drive
Review maximum/minimum cell voltage and delta
Check whether historical fault codes return after clearing
Look for abnormal single-point temperature deviation

Red flags to treat seriously

Low SOH with refusal of recheck
Abnormal voltage delta plus fault codes
Fault returns after clearing
Long-term uneven temperature distribution

Questions to ask

Ask the seller or inspector this way

Anchor questions to verifiable records, diagnostic items and written commitments to reduce information gaps.

What equipment and timing were used to read SOH?

What is the cell voltage delta at the current SOC?

Are there historical BMS or insulation-related fault codes?

Do faults return after clearing and test driving?

Continue reviewing

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