This book deals with synthesis and characterization for N,N -bismaleimide-4,4 -diphenylmethane (BMI) /barbituric acid (BTA) and phenylsiloxane-modified BMI/BTA with 3-aminopropyltriethoxysilane as the coupling agent. In addition, the thermal stability of organofunctional polysiloxanes including glycidyloxypropyl polysiloxane, aminopropyl polysiloxane, methacryloxypropyl polysiloxane and vinyl polysiloxane was investigated. Non-isothermal free radical polymerization kinetics for BTA/bisphenol A diglycidyl ether diacrylate (EA) and benzoyl peroxide (PBO)/EA in n-methyl-2-pyrrolidone were investigated. Finally, non-isothermal degradation kinetics and mechanism of cured polymers of BTA/EA and BPO/EA were characterized. These polymers can be used as polymeric additive for effectively improving the key performance of lithium-ion batteries. Lithium-ion battery systems embedded with a relatively low level of BMI/BTA polymer provide the multi-protective mechanism to prevent batteries fromthermal runaway and ultimate explosion.