Standardized Scheme for Battery Replacement Evaluation of Electric Forklifts

This scheme clarifies the replacement evaluation indicators, testing methods, responsible entities, and abnormal handling procedures for lead-acid batteries and lithium-ion batteries. It aims to ensure the timely replacement of degraded batteries and avoid impacts on operational safety and efficiency.

I. Core Evaluation Indicators (Quantitative Standards)

1. Capacity Degradation Indicator (Core Evaluation Basis)

The actual capacity of the battery is tested with a professional discharge meter and compared against the rated capacity. Replacement is required if any of the following conditions are met:

Supplementary Note: If the capacity degradation rate in a single test exceeds 10% (compared with the data from the previous test), even if the threshold is not reached, the key monitoring procedure shall be initiated, and the testing frequency shall be shortened to once a month.

2. Cycle Life Indicator

Based on the number of battery charge-discharge cycles, mandatory replacement is required when the following limits are reached accompanied by reduced cruising range:

3. Cruising Range and Operational Efficiency Indicators (On-site Rapid Evaluation)

No professional equipment is needed; evaluation can be conducted based on daily operational data. Replacement is required if any of the following conditions are met:

• The cruising range after full charge is less than 50% of the rated cruising range (e.g., the rated cruising range is 8 hours, but the actual working time is within 4 hours);
• Frequent power shortage occurs during operation (e.g., a sudden ｄｒｏｐ in motor speed when climbing with full load, failure to lift or lower the forks normally);
• Abnormally shortened charging time (e.g., a lead-acid battery that originally takes 8-10 hours to fully charge now shows full charge in 2-3 hours with an extremely fast discharge rate).

4. Safety and Appearance Abnormality Indicators (Mandatory Replacement Conditions)

If any of the following physical or safety abnormalities occur, stop the machine immediately for replacement and prohibit further use:

II. Standardized Testing Process (Implementation Steps)

Daily Inspection (Performed by Operators)

• Implementation Frequency: Once per shift before the start of daily work
• Testing Content: Battery appearance (presence of bulging or leakage), terminal cleanliness, charging interface condition
• Testing Tools: Multimeter

Capacity Test (Performed by the Operation and Maintenance Team)

1. 1.Let the fully charged battery stand for 2 hours, then discharge it at a constant current of 0.2C, and record the time when the voltage drops to the cut-off voltage.
2. 2.Calculate the actual capacity = discharge current × discharge time, and compare it with the rated capacity.
3. 3.Record the test results in the battery full-life cycle ledger and mark the degradation trend.

BMS Data Diagnosis (Exclusive to Lithium Batteries)

• Implementation Frequency: Once a month
• Operation Content: Read data such as cell voltage, temperature, and cycle times in the BMS using the battery supplier’s dedicated diagnostic software.
• Evaluation Standard: If cell consistency is poor (voltage difference > 0.2V) or the number of cycles is close to the threshold, initiate the replacement evaluation process.

III. Replacement Decision-making and Abnormal Handling Process

Evaluation Process

Operator reports the abnormality → Operation and maintenance team conducts on-site testing → Battery supplier reviews the data → Operation and maintenance supervisor issues a battery replacement notice.

Emergency Handling Process

Upon discovery of serious safety hazards such as battery bulging, leakage, or odor → Cut off the power immediately to isolate the faulty battery → Arrange special tools to transport it to the designated storage area → Contact the supplier for recycling and disposal → Prohibit disassembly or disposal without authorization.

Post-replacement Verification

After installing the new battery, conduct the first charge-discharge test: perform 2 hours of full-load operation after full charge to verify whether the cruising range and power meet the standards, and calibrate the BMS data simultaneously.