Tests of Newly Manufactured Lithium Batteries

Newly manufactured lithium batteries need to undergo a series of rigorous tests to ensure their performance, safety, and reliability. Below is a detailed summary of these tests:

I. Physical Property Tests

1. Dimension and Weight Test:

Measure the dimensions and weight of the battery to ensure they comply with design specifications.

2. Visual Inspection:

Check for any defects or damage on the battery’s casing, terminals, and labels.

3. Housing Strength Test:

Apply pressure or compression to test the strength and durability of the battery housing.

II. Electrical Performance Tests

1. Capacity Test:

Use specific charging and discharging equipment to measure if the battery’s discharged capacity meets the nominal capacity according to set currents and times.

2. Internal Resistance Test:

Employ a professional internal resistance tester to measure the battery’s internal resistance under different states (e.g., charging, discharging, resting). Internal resistance reflects the size of the battery’s internal resistance and significantly affects the battery’s power output, charging efficiency, and self-discharge.

3. Voltage Test:

Includes the measurement of open-circuit voltage and operating voltage. Open-circuit voltage refers to the terminal voltage of the battery when no load is connected, while operating voltage is the actual output voltage under load. Testing voltage changes under different conditions can assess the stability of the battery’s performance and its compatibility with devices.

4. Rate Performance Test:

Test the battery’s performance under different charge and discharge rates. Higher rates mean larger currents. For example, test the battery’s capacity, internal resistance, and voltage at different rates such as 0.5C, 1C, 2C, etc., to understand the performance changes during fast charging and discharging and whether it can meet the needs of high-power applications.

5. Self-Discharge Test:

Measure the rate at which the battery naturally discharges in a resting state. The lower the self-discharge rate, the better the battery’s storage performance.

6. Discharge Characteristic Test:

Includes the battery’s discharge curve and discharge efficiency.

III. Safety Tests (These tests need to be conducted in specialized testing institutions equipped with professional testing equipment and technicians to ensure accuracy, reliability, and detailed test reports and certifications)

1. Overcharge Test:

Simulate the battery’s performance under overcharging conditions and check if the battery has safety protection mechanisms, such as triggering overcharge protection circuits, battery heating, swelling, or fire and explosion.

2. Overdischarge Test:

Inspect the safety of the battery when it is overdischarged. Overdischarge can cause irreversible damage to the battery and reduce its lifespan.

3. Short Circuit Test:

Artificially create a short circuit between the battery’s positive and negative poles to observe the effectiveness of the short circuit protection and any temperature changes, smoke, or fire during the short circuit.

4. Nail Penetration Test:

Pierce the battery with a sharp object (like a steel nail) to simulate the situation when the battery is punctured by a sharp object, checking for violent chemical reactions, fire, or explosion.

5. Crush Test:

Place the battery in a crushing device and apply pressure to test the safety and stability of the battery under external force compression.

6. Impact Test:

Apply sudden impact force to the battery to test its safety and stability when subjected to external impact.

7. Thermal Stability Test:

Place the battery in different temperature environments (e.g., high temperature, low temperature) and observe changes in battery performance and whether thermal runaway occurs.

IV. Environmental Adaptability Tests

1. Temperature Cycling Test:

Subject the battery to multiple cycles between different temperature ranges, such as from low to high temperature and back to low temperature, to test the stability and reliability of the battery’s performance under temperature changes.

2. Humidity Test:

For lithium batteries that may be used in humid environments, such as outdoor equipment batteries, humidity tests are needed to assess performance and reliability in high-humidity conditions.

3. Vibration Test:

Simulate the vibration that batteries may experience during transportation and use to test the structural strength and connection reliability.

4. Low Pressure Test:

Simulate the use of batteries in high-altitude or low-pressure environments to check for leakage or swelling.

Other Tests

Electromagnetic Compatibility (EMC) Test:

Assess the battery’s interference and immunity in electromagnetic environments.

Environmental Performance Test:

Detect the content of heavy metals and hazardous substances in the battery to ensure compliance with environmental requirements.

Cycle Life Test:

Observe the battery’s capacity degradation by performing multiple charge and discharge cycles to assess the battery’s service life.

In summary, newly manufactured lithium batteries require a comprehensive and rigorous series of tests to ensure their performance, safety, and reliability. These tests cover physical properties, electrical performance, safety, environmental adaptability, and other aspects, providing strong assurance for battery quality control and subsequent applications.