EN 14477 Puncture Resistance of Flexible Packaging Material
EN 14477 and Lithium-Ion Battery Testing
EN 14477 is an increasingly important testing standard due to the increasing popularity of lithium-ion batteries. Lithium-ion batteries include a separator material - the membrane between the battery’s anode and cathode - which has become increasingly thinner as manufacturers seek to improve conductivity and minimize the amount of space that it occupies. These separator films are commonly made from polymers and must be mechanically strong enough to withstand the winding operation during assembly of the battery. From a material evaluation standpoint, understanding the mechanical properties such as puncture resistance is important when determining which material is optimal.
Standard At A Glance
- EN 14477
Instron’s custom puncture fixture, CP105780, was designed per EN 14477 and includes two 0.8 mm diameter puncture probes. The fixture includes an essential rubber ring that goes between the specimen and fixturing body, which is necessary to prevent the specimen from moving around or slipping during testing. Instron also offers a 1 mm diameter puncture probe, CP114502, as an add on or replacement for the 0.8 mm diameter probs. Though the 1 mm diameter probe deviates from the standard, it can be used in various cases to evaluate the puncture resistance of thin film materials.
Materials Testing System
EN 14477 recommends a Constant Rate of Extension (CRE) frame able to operate and measure elongation during testing. If testing is to be performed with slower tests speeds, an Instron 3400 Series test frame should suffice. However, for best results when testing at 50 or 100 mm/min, a 6800 Series frame is the optimal solution due to its higher data capture rate. For nearly all thin film puncture testing, a single column frame is appropriate as the loads rarely go above 5 kN. For most thin film puncture testing to EN14477, Instron’s 2530 Series load cells are appropriate. A 10 N load cell is typically sufficient for testing materials such as separator film; however, larger 50-100 N load cells can be used as well based on the thickness and strength of the material.
Instron’s Bluehill Universal testing software has options for controlling the data rate and speed for each test to ensure the material is evaluated at various test parameters. Bluehill software allows users to easily control the test, acquire data, and prepare test reports. Because puncture testing per EN 14477 can be performed up to speeds of 100 mm/min, it is recommended to use a high data rate in order to capture the true peaks in load, as it occurs very quickly at high speeds. An insufficient data rate can result in variable testing results if the peaks are not captured adequately.
|EN 14477 Test Setup|
|1)||6800 Series Universal Testing System
|2)||Bluehill Universal Software
|3)||CP105780 Custom Test Fixture
Instron 6800 Series Universal Testing Systems provide unparalleled accuracy and reliability. Built on a patent-pending Operator Protect system architecture with an all-new Smart-Close Air Kit and Collision Mitigation features, the 6800 Series makes materials testing simpler, smarter, and safer than ever before.
Bluehill Universal Software is built from the ground-up for touch interaction and an intuitive user experience. Discover simpler and smarter testing with features such as pre-loaded test methods, QuickTest in seconds, enhanced data exporting: and Instron Connect – a new feature that provides a direct communication link to Service. Users of previous versions of software such as Bluehill 2 and Bluehill 3 can easily upgrade to the newest version of Bluehill.
Instron 2530 series load cells are specifically designed for use with any of Instron's low force testing systems. Force capacities range from ±5 - ±100 N (0.5 – 10 kgf, 1.12 – 22.5 lbf) with a wide measurement range allowing force to be measured down to 1/500th of the load cell's capacity.