Challenges of EV Battery Testing

There are several challenges in battery testing, which include:

Ensuring the accuracy and reliability of test results: It is important to have consistent and reliable test results to accurately determine the performance and durability of batteries.

Testing the full range of operating conditions: Batteries are used in a wide range of operating conditions, including extreme temperatures, high humidity, and rough terrain. It is challenging to accurately simulate these conditions in a laboratory setting.

Testing for long periods of time: Batteries are expected to last for many years. It is difficult and time-consuming to test batteries for such long periods of time.

Ensuring the safety of test personnel: Batteries contain large amounts of energy and can be dangerous if handled improperly. It is important to have safety measures in place to protect test personnel.

Dealing with the cost and complexity of testing equipment: Testing batteries can be expensive, requiring specialized equipment and facilities. It is also complex, as it involves multiple stages of testing and data analysis.

A&D’s Battery Testing solutions will help simplify the process by reducing the complexity of controlling the specialized battery test equipment.

The A&D Solution

With over 15 years of experience in battery test automation, A&D’s battery test systems are perfect for battery-end-of-line and in-line testing. Production battery testing requires many complex tests that must be executed repeatedly and quickly. The many customizable features of A&D’s iTest.BTS makes the implementation and control of these tests manageable. Features such as custom operating modes and parameterized test schedules allow the system to be easily configured to test any battery without modifying the test schedule.

A&D’s LabWorX lab management software can manage all the tests and store the data in one convenient platform. A&D’s iTest test automation software can help automate and streamline all of the different in-line and end-of-line battery tests. And don’t worry, if you need to expand your testing and add more battery test equipment later, our solutions are expandable! A&D can always revisit your initial solution to integrate new equipment into your streamlined testing process.

A&D not only provides our industry-leading battery test automation and management software, but we can also consult with your team to help with the battery test equipment vetting and procurement process. Then, we’ll design the systems together using our software to deliver a complete battery EOL testing solution. If your company has custom EOL or in-line testing needs, whether it be for batteries, eMotor test stands, eAxle test stands, or something else, don’t hesitate to contact A&D and we can discuss engineering a custom solution.

A&D’s iTest.BTS Battery Test Automation System provides a flexible and easy to use test automation platform. Whether testing cells, modules or fully assembled packs A&D can implement a dependable custom solution, which will provide reliable results test after test. iTest.BTS solutions are open and customizable to allow modifications required to suit the ever changes requirements of battery testing.

Easy to use test schedules allow test engineers to quickly modify test procedures with having to know any programming languages. iTest.BTS offers an offline development package, so changes to test schedules can run under simulation before ever committing to a running test. This helps mitigate losing test time due to development changes.

For more extensive modifications, iTest.BTS features built-in scripting with Python or A&D’s VCL scripting language. Both scripting tools provide users will all the necessary tools and system access to implement or modify operating procedures if required.

A&D’s LabWorx integrated suite of lab management tools can be integrated into any test system to help manage the large amounts of data generated by production battery testing. LabWorX is a server application for integrated management of tests, test facilities, and data. It can be displayed and operated using a web browser and managed in an environment away from the work site. The LabWorx suite includes remote monitoring of test equipment, test schedule management, centralized management of measurement data, automatic report generation, and many other features.

With over 15 years of experience in battery testing, why not put A&D’s experience to work on building an End-of-Line or In-Line battery test system. Please contact A&D with a list of requirements for a quotation.

Common Battery Test Scenarios

Battery Pack EOL – checks the functionality of the full battery pack after the external cover has been installed before the battery pack leaves the factory.

Battery Module EOL – confirms proper module assembly and electrical operation before assembly into a pack system.

Battery Pack In-Line (IL) -performs visual inspection, electrical tests, and temperature measurements to verify the pack was assembled according to specifications.

Below are some of the types of tests A&D can incorporate into our custom End-of-Line or In-Line test solutions:

End-of-Line Battery Tests

End-of-line testing for battery packs and modules typically involves a series of tests to ensure that the battery meets the required performance standards.

End-of-Line tests typically conducted include:

Battery Management System – verifies the BMS is reading all internal battery sensors, clears any Diagnostic Trouble Codes (DTC) codes, and checks firmware revision levels before closing pack contactors

High Voltage Test – measures the insulation resistance and battery HV withstand test

Temperature Sensor Verification – checks that all internal temperature sensors are reading values within the specified tolerance range

Safety Interlock Checks – confirms the battery connection interlock links are functioning properly

Battery Internal Contactors Operation – opens and closes contactors to verify their operation with the BMS control and detection functions

Cell Voltage – measures the cell voltages to check that minimum, maximum and delta voltages are reading properly and within tolerances

Pack Voltage – verifies the BMS internal pack voltage measurement matches the pack output voltage

DC Internal Resistance Measurement – performs charge/discharge pulse and calculates the internal resistance of the battery pack

Charge/Discharge Pulse Test – a short charge/discharge cycle to ensure the battery charges, discharges, and the BMS responds correctly to each cycle

Battery Management Programming – clears any DTC codes generated during testing, updates cell voltage and temperature information, reads/writes any data acquired during the test.

In-Line Battery Tests

In-line testing for electric vehicle (EV) battery packs typically involves a series of tests that are performed as the battery is being manufactured to ensure that it meets the required performance standards.

In-line tests typically conducted include:

Visual Inspection – inspects the battery modules for proper installation and connections visually or with a video camera

Measured Capacity – conducts several charge and discharge cycles to determine battery capacity

Charge/Discharge – fully charges and discharges battery to approximately 30% State of Charge (SOC)

Connection Test – measures temperature at cell and module connections using thermal imaging for hot spots indicating a bad connection while charging and discharging a battery

Capacity Test – measures the total amount of energy that the battery can store

State of Charge Determination

Leakage Test – applies pressurized air while monitoring for any leaks

Weighing – ensures that the battery cells and pack are within the specified weight range

Dimensional Inspection – ensures that the battery cells and pack are the correct size and shape

Soldering Inspection – ensures that the battery cells are properly soldered to the pack

Thermal Imaging – detects any hotspots or areas of increased temperature in the battery pack that could indicate a problem

Pack Assembly Inspection – ensures that the battery pack is properly assembled, and all components are properly connected