Electrode Anode Testing for Electric Vehicle Batteries

The most commonly performed peel tests are 90° and 180° peel tests. 180° testing has an advantage over 90° testing in simplicity of setup and ease of alignment. This testing can be done using low force grips and load cells along with a substrate that helps the flexible material maintain proper alignment during testing. It is best to consider pneumatic grips and a metal substrate to ensure high throughput and a proper 180° peel throughout each test.

90° peel testing is commonly seen as an alternative to 180° degree peel testing. The 90° peel test generally involves slightly higher loads than the 180° peel test and can be set up more quickly because it often does not require a substrate. Instron’s most common solutions for this testing are a standard 90° peel fixture or a pneumatic peel fixture designed specifically to test the adhesion of electrodes. The pneumatic 90° peel fixture was developed specifically for electrode adhesion testing and provides improved repeatability and throughput while also aiding the operator in consistent specimen placement and alignment at 90°. For the upper fixture, a pneumatic grip optimizes throughput and repeatability and is recommended for testing delicate materials.

A tack test is an electrode adhesion test that has been backed by researchers as an additional way to test the adhesion of electrodes to a battery's current collector. Instead of slowly peeling electrodes from the current collector, a tack test focuses on the adhesion strength of an entire predetermined area of electrodes, allowing for quicker evaluation of electrode adhesion over a large area. Instron’s tack testing fixture is designed for ease of specimen preparation as well as high throughput and repeatability. It features predetermined contact areas in addition to a spherically seated and lockable upper fixture, which ensures parallelism between both fixtures. Due to the fast speeds of this testing, a testing system with a very high data rate collection will ensure the best possible results and throughput.