| CPC H01M 10/0567 (2013.01) [H01M 10/0525 (2013.01); H01M 10/0568 (2013.01); H01M 10/0569 (2013.01)] | 15 Claims | 
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               1. An electrolyte for a secondary battery, the electrolyte comprising: 
              a lithium salt; 
                a nonaqueous organic solvent; and 
                a cyclic fluorophosphonate compound represented by the following Chemical Formula 1: 
              ![]() wherein 
                R1 and R2 are independently of each other hydrogen, C1-C10alkyl, halogen, C1-C10alkoxy, C3-C10cycloalkyl, or C6-C20aryl, and the alkyl, alkoxy, cycloalkyl, or aryl may be further substituted by one or more selected from the group consisting of C1-C10alkyl, halogen, haloC1-C10alkyl, C1-C10alkoxy, C1-C10alkoxyC1-C10alkyl, C3-C10cycloalkyl, and C6-C20aryl; 
                A is —(CRaRb)m—, C3-C10cycloalkylene, or C6-C20arylene, and the cycloalkylene or arylene may be further substituted by one or more selected from the group consisting of C1-C10alkyl, halogen, haloC1-C10alkyl, C1-C10alkoxy, C1-C10alkoxyC1-C10alkyl, C3-C10cycloalkyl, and C6-C20aryl; 
                Ra and Rb are independently of each other hydrogen, C1-C10alkyl, halogen, C1-C10alkoxy, C3-C10cycloalkyl, or C6-C20aryl, and the alkyl, alkoxy, cycloalkyl, or aryl may be further substituted by one or more selected from the group consisting of C1-C10alkyl, halogen, haloC1-C10alkyl, C1-C10alkoxy, C1-C10alkoxyC1-C10alkyl, C3-C10cycloalkyl, and C6-C20aryl; and 
                m is an integer of 1 to 5. 
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