The invention belongs to the field of 
lithium ion batteries, and particularly discloses a high-temperature 
electrolyte which comprises the following components in percentage by weight: 2-20% of 
lithium salt; 0.01%-20% of a high-temperature additive; 70%-90% of a non-aqueous 
organic solvent; and 0.1%-10% of other additives. The invention also provides a 
lithium battery which comprises a positive 
electrode, a negative 
electrode, a diaphragm and the 
electrolyte. The high-temperature additive added into the 
electrolyte contains a large number of anhydride groups, can form an interface film with good and stable performance on the surface of an 
electrode in battery circulation, inhibits 
dissolution of positive electrode 
metal ions at high temperature, participates in formation of a passive film on the surface of a negative electrode, modifies the structure and components of an SEI film, and improves the high-temperature and circulation performance of the battery; the introduced 
sulfonate group can form a stable SEI film on the surface of the negative electrode, the impedance of the SEI film is not increased after high-temperature storage, the capacity 
recovery rate is relatively high, and the high-
temperature cycling stability of the battery is improved.