How to Measure Battery Internal Resistance Using Battery Analyzer to Assess Battery Health and Lifespan

Measuring battery internal resistance using a Battery Analyzer is a crucial method for assessing battery health and lifespan. Below are the detailed steps and methods:

Preparation Stage

1. Equipment Preparation:

• Ensure the Battery Analyzer is functioning properly and has the capability to measure battery internal resistance.

• Prepare the necessary connecting cables and adapters for correct connection to the battery.

2. Sample Preparation:

• Select the battery to be tested, ensuring it has sufficient charge and is well-mixed (for stirable batteries).

• Place the battery in a temperature-controlled chamber to maintain a constant temperature, eliminating the impact of temperature on measurement results.

Setting Test Parameters

1. Constant Current Source Selection:

• Choose a relatively small constant current source based on the battery's rated current. A smaller current source can better reflect the battery's true performance while avoiding excessive load on the battery.

2. Measurement Voltage Range Setting:

• Select an appropriate measurement voltage range based on the battery's rated voltage and test accuracy. Ensure the range covers the battery's rated voltage and meets the test accuracy requirements.

Conducting the Test

1. Connecting the Battery:

• Connect the battery to the Battery Analyzer correctly, ensuring a secure and accurate connection.

2. Starting the Test:

• Initiate the Battery Analyzer to begin testing. Record the test duration and the change in sample voltage over time.

• Regularly check and record the battery's temperature during the test to ensure the accuracy of the results.

Data Processing and Result Analysis

1. Calculating Internal Resistance:

• Calculate the internal resistance value at each time point by dividing the difference between the constant current source and battery voltage by the constant current source.

2. Plotting Internal Resistance Change Curve:

• Plot a graph of internal resistance changes over time to visually understand the trend.

3. Assessing Battery Health:

• Evaluate battery health based on the internal resistance trend. Generally, an increase in internal resistance indicates a decline in battery performance and increased aging.

4. Predicting Lifespan:

• Combining the battery's initial internal resistance, internal resistance change rate, and other relevant parameters, predict the battery's lifespan. This helps users replace batteries in a timely manner, avoiding losses due to battery failure.

Calibration and Validation

1. Equipment Calibration:

• Regularly calibrate the current source and voltmeter of the Battery Analyzer before measuring battery internal resistance to ensure measurement accuracy.

2. Validating Test Methods:

• To validate the feasibility of the test method, select some standard batteries with known internal resistances for testing and compare them with the known values. If the test results match the known values or the error is within an acceptable range, the test method is reliable.

By following these steps, you can accurately measure the battery's internal resistance and assess its health and lifespan accordingly. This is significant for battery research, production, and application, contributing to the further development of battery technology.