{"id":948,"date":"2019-05-28T00:00:00","date_gmt":"2019-05-27T23:00:00","guid":{"rendered":"https:\/\/www.innovationnewsnetwork.com\/calorimeters-battery-safety\/948\/"},"modified":"2021-03-03T09:32:52","modified_gmt":"2021-03-03T09:32:52","slug":"calorimeters-battery-safety","status":"publish","type":"post","link":"https:\/\/www.innovationnewsnetwork.com\/calorimeters-battery-safety\/948\/","title":{"rendered":"Why calorimeters are essential to improve battery safety"},"content":{"rendered":"

Safety testing in battery calorimeters<\/a> paves the way for improved understanding and prevention of thermal runaway.<\/h2>\n

Established in 2011, the Calorimeter Center at the Karlsruhe Institute of Technology\u2019s (KIT) Institute for Applied Materials \u2013 Applied Materials Physics, now operates Europe\u2019s largest battery calorimeter laboratory. It provides six Accelerating Rate Calorimeters (ARCs) of different sizes \u2013 from coin to large pouch or prismatic automotive format, which allow the evaluation of thermodynamic, thermal and safety data for Lithium-ion and post-Lithium batteries on material, cell, and pack level for both normal and abuse conditions (thermal, electrical, mechanical).<\/p>\n

Safety first<\/h3>\n

Safety comes first \u2013 this is the mission of the centre\u2019s head, Dr Carlos Ziebert. It is clear that safety issues have a major influence on consumers\u2019 willingness to adopt battery systems. A holistic safety assessment is a prerequisite for upscaling and market acceptance of battery technologies, because an uncontrollable increase in temperature of the entire system (so-called \u2018thermal runaway\u2019) can cause ignition or even explosion of the cell that leads to negative public attention or even rejection.<\/p>\n

The causes and effects of thermal runaway can be very diverse and complex (see Figure 1). Either internal or external mechanical, operating, or thermal stresses lead to an internal heating of the cell that initiates different exothermal reactions, followed by a further temperature and pressure increase. The final effects can be empirically classified by the Hazard Level (1-7). Cell designs, component integrity, manufacturing, and ageing processes all have critical influence on the safety of Li-ion batteries.<\/p>\n

Battery calorimetry benefits<\/h3>\n

Calorimetry \u2013 or the process of measuring heat data during chemical reactions \u2013 allows the collection of quantitative data required for optimum battery performance and safety. Sophisticated battery calorimetry combined with thermography allows finding new and quantitative correlations between different critical safety and thermally related parameters. This is very important because you need to know how many Watts a cell will produce under every condition in order to adapt the battery and thermal management systems. The temperature, heat, and internal pressure evolution can be studied, while operating cells under conditions of normal use, abuse, or accidents. Such abuse tests without a calorimeter have two main disadvantages:<\/p>\n