Lithium secondary battery using ionic liquid

A lithium secondary battery comprising:

• a positive electrode;
• a negative electrode;
• a separator provided between said positive electrode and said negative electrode;
• and
• a non-aqueous electrolyte, wherein the non-aqueous electrolyte includes, as a solvent, an ionic liquid containing a bis(fluorosulfonyl) imide anion as an anion component and said separator has a porosity of between 85% and 95%, inclusive, and more than 80% of the mass of the separator includes glass fiber and less than 20% of the mass of the separator comprises said organic fiber.

A lithium secondary battery comprising:

• a positive electrode;
• a negative electrode;
• a separator provided between said positive electrode and said negative electrode;
• and
• a non-aqueous electrolyte containing a lithium salt, wherein said non-aqueous electrolyte includes, as a solvent, an ionic liquid containing a bis(fluorosulfonyl) imide anion as an anion component and the separator is a nonwoven fabric including at least one member selected from an organic fiber and a glass fiber and has a porosity between 85% and 95%, inclusive, and more than 80% of the mass of the separator includes said glass fiber and less than 20% of the mass of the separator comprises said organic fiber.