Lithium primary battery and liquid non-aqueous electrolyte for lithium primary battery

A lithium primary battery, comprising:

• a positive electrode;
• a negative electrode;
• and a liquid non-aqueous electrolyte, wherein the positive electrode contains a positive electrode material mixture including LixMnO2 where 0≤x≤0.05,
• the negative electrode contains at least one selected from the group consisting of metal lithium and a lithium alloy,
• the liquid non-aqueous electrolyte contains an additive containing a cyclic imide component and an additive containing an organic silyl borate component,
• the cyclic imide component includes at least one selected from the group consisting of phthalimide and a N-substituted phthalimide,
• the organic silyl borate component includes tris(trimethylsilyl) borate,
• a concentration of the cyclic imide component in the liquid non-aqueous electrolyte is 0.1 mass % or more and 1 mass % or less,
• a concentration of the organic silyl borate component in the liquid non-aqueous electrolyte is 0.1 mass % or more and 5.5 mass % or less, and
• a mass ratio of the cyclic imide component to the organic silyl borate component contained in the liquid non-aqueous electrolyte is 0.1 or more and 0.5 or less.