Battery health in the fleet: document SOH values with a clear evidence trail

State of Health, or SOH, describes a battery's health or ageing condition according to a particular assessment method. Alongside the result, fleet management therefore needs to know which property was determined, what the assessment is based on and which vehicle it belongs to. A single percentage without supporting evidence is not enough for a reliable condition record.

Fleet software can help keep reports, data versions and next review steps organised and available. It does not replace a specialist battery diagnosis or a repair decision. This guide shows how to organise SOH documentation usefully throughout the vehicle lifecycle.

First ask what the result means

Read the condition report to establish what the stated SOH actually expresses. Does it refer to a capacity assessment? What reference value is used? What measurement or data analysis underlies it? If this explanation is missing, the result remains incomplete for your decision.

The technical information on SOH determination explains that different measurement and analysis methods affect how battery condition is interpreted. The complete report is therefore essential for your documentation, including the method and conditions.

Do not infer a general remaining service life from an SOH figure. Operational questions, such as the next assignment or a vehicle return, need additional information. First record which specific decision is being prepared and which documents it requires.

Create a complete entry for each condition report

Link every report to the stable vehicle ID. Record the vehicle identification number, date, mileage and the battery reference given in the report, where available. This is particularly relevant after a battery replacement or a documented technical change.

A practical entry includes these fields:

A manually transcribed figure should refer to the original report. This allows a colleague providing cover to check whether the unit, rounding and reference have been transferred correctly. The digital vehicle record for electric cars provides the organisational framework.

Schedule checks for specific reasons

Define when your operations need evidence of battery condition. Possible triggers include adding a used vehicle, an unusual operational observation, a contractually agreed return or a documented service event.

Take deadlines and requirements from the documents that apply to the vehicle. A self-imposed appointment in the software does not confirm that a particular report meets all contractual requirements. The responsible specialist team should define which report is needed and who evaluates it.

Describe observations precisely. “Battery bad” does not describe a case that can be acted on. “Under documented conditions, the planned assignment lacks the expected energy reserves” states a question whose cause can be investigated. The battery is not assumed to be the cause without investigation.

Example: a condition report before vehicle return

Illustrative working scenario: Vehicle EV-032 is due to be returned in eight weeks. Its record contains a nine-month-old report with an SOH result of 91 percent. When it is opened, the team notices that the method is missing from the data entry, although it is described in the complete report.

The team adds the missing method reference and checks the return documentation to determine which current evidence is required. An appointment is created with a responsible person and the expected document type. The older report remains as historical evidence.

Once the new report arrives, the responsible person checks the vehicle reference, date and completeness. Only then is the case closed. The 91 percent has not been treated as either a guaranteed return value or a statement about a possible claim.

Use a checklist for approval and ongoing records

Before filing the report, check that it is fully readable and relates to the correct vehicle. Add missing information through a documented follow-up question. A report with outstanding questions receives the corresponding status; it does not disappear among already completed documents.

This checklist is useful for ongoing maintenance:

• What triggered the assessment?

• Which property does SOH describe in the report?

• Are the date, vehicle reference and method traceable?

• Have technical changes been considered in the history?

• Which technical statement does the report actually support?

• Who evaluates outstanding issues, and by when?

• Which subsequent decision has been documented?

If a value changes noticeably, first check the documents and measurement conditions. A figure must not automatically trigger a technical intervention solely because of its level or change. You can connect planned inspections and workshop appointments with maintenance management in an electric fleet.

You can discuss your fleet requirements with StromNow to coordinate vehicle organisation and charging processes. Whether existing systems manage SOH reports or the relevant data fields is part of your specific functional review.