Performance-Focused Analysis of Fire-Blocking Blanket for Lithium Ion Battery Fires

Abstract

So far too long, people have been working hard to develop fire prevention measures to deal with lithium ion battery (LIB) fires. LIB fires have a high calorific value, a rapid burning and spread speed and a high risk of re-ignition and explosion. Under thermal runaway, LIB fires develop from the inside out, preventing fire extinguishing agents from entering the interior of LIB, thus resulting in low extinguishing efficiency or even failure of the extinguishing agents. Based on the principle of ‘isolation and stifling’, fire-blocking blanket can effectively inhibit the spread of fire, suppress the combustion intensity and reduce the smoke emission. This paper digs into the detailed performance requirements of fire blanket to block LIB fires. By conducting laboratory tests to mimic LIB fires, the candidate materials including fiber materials, woven textile and woven fabrics with organic coatings are systematically investigated. Performance of the materials are evaluated, including fire resistance, thermal insulation, tensile strength at break and blast resistance, respectively. The testing results help to screen out the best material for LIB fire blanket, and high-silica glass fiber coated by polyurethane has the best thermal and mechanical properties among all materials tested. This paper also presents a three-layer structured design of blanket, which can pass all the tests proposed.