Comprehensive Battery Testing Methods for Performance, Safety, and Reliability Evaluation

Although the design engineer can directly measure all of the cell parameters they desire, this is not always practical or feasible. By fully discharging the battery and measuring the energy output, for instance, it is possible to determine how much charge is still in the battery, or the State of Charge (SOC).

Test Conditions

In order to obtain repeatable results and make meaningful comparisons, the test conditions must be clearly defined.

Qualification Testing

Before a cell or battery is permitted for use in a product, qualification testing is used to ascertain whether it is suitable for the intended use.
Prior to the product being authorised for distribution to the customer, a finished battery pack must also pass Cell testing as a second stage of qualification.

Environmental Testing

The safety standards listed below incorporate typical tests. They are made to put the product through all of the environmental conditions that it is likely to experience over the course of its lifetime.

Abuse Testing

The goal of battery abuse testing is to make sure that the battery won’t pose a risk to the user or to itself through accidental or intentional misuse under any scenario that could arise.

Cycle Testing

The significance of this qualification test is debatable. The number of charge-discharge cycles a battery can complete before its nominal capacity drops below 80% of its initial rated capacity is the standard definition of cycle life. Both excessive charging and excessive discharging reduce cycle life.

Load Testing

To ensure that the battery can deliver the required amount of power when required, load testing is used. Typically, the load is created to be an accurate representation of the anticipated usage scenarios for the battery.
In low-power testing, resistive loads are typically used.

Calorimetry

The total amount of heat produced by the battery during its charge/discharge cycles is measured using a calorimeter.

Electromagnetic Compatibility (EMC) testing

It refers to the capacity of electrical and electronic devices and systems to function without interfering with other electrical or electronic devices or being influenced by other sources of interference, such as lightning, radio frequency (RF) signals, digital pulses, electrical machinery, or other influences.

Process audits

Another method of ensuring the quality of the cells under consideration is to conduct a process audit of the cell manufacturer’s production facilities; however, this option is typically only open to major purchasers of high-volume or expensive cells.

Inspection and Production Testing

Inspection production testing is done to ensure that the purchased cells and the products made from them meet the agreed-upon specifications. These are usually quick tests run on either a representative sample or 100% of the throughput.

Battery Analysers

Battery analysers are made to give a quick indication of the battery’s State of Health (SOH). Some analysers can also condition batteries.

Types Of Production-Level Testers

Thermocouple

Temperature measurements are made using a thermocouple.

Electrochemical Impedance Spectroscopy

It helps to take measurements of the impedance and helps to determine the state of health (SoH) and state of charge (SoC) of the battery pack.

PAT Cells

To measure the electrode properties of the battery components testing, use the PAT Cell.

Although it may appear that production-level battery testers extend the time required for battery pack assembly, in reality, because the production testers were used earlier in the procedure, additional tests may not be necessary.