The non-aqueous electrolyte secondary cell according to an embodiment of the present disclosure has a positive electrode, a negative electrode, and a non-aqueous electrolytic solution. The negative electrode has a negative electrode collector and a negative electrode active material layer provided on the negative electrode collector. The negative electrode active material layer contains graphite particles A and graphite particles B as negative electrode active materials. The graphite particles A have an internal void rate of 5% or below. The graphite particles B have an internal void rate of 8 to 20%. When the negative electrode active material layer is halved in the thickness direction, a region on the half closer to the outer surface contains more graphite particles A than a region on the half closer to the negative electrode collector.

The present disclosure relates to an electrolyte comprising at least one magnesium salt having a polyatomic anion, an aluminium halide salt and a solvent comprising at least one ether group. The electrolyte described herein does not comprise magnesium chloride. The electrolyte described herein may be used in magnesium ion electrochemical cells.

The present disclosure relates to an electrolyte comprising at least one magnesium salt having a polyatomic anion, an aluminium halide salt and a solvent comprising at least one ether group. The electrolyte described herein does not comprise magnesium chloride. The electrolyte described herein may be used in magnesium ion electrochemical cells.

An electrolyte for a lithium-ion battery includes a primary lithium salt and an organic compound composition. In some designs, the organic compound composition includes (1) fluoroethylene carbonate (FEC), (2) vinylene carbonate (VC), (3) at least one ester (ES), and (4) a nitrile additive composition (NAC) which includes at least one nitrile compound. In some designs, a mole fraction of the NAC in the electrolyte is in a range of approximately 0.1 mol. % to approximately 2.0 mol. %. In some designs, a mole fraction of the at least one ES in the electrolyte is at least approximately 35 mol. %.

An electrolyte for a lithium-ion battery includes a primary lithium salt and an organic compound composition. In some designs, the organic compound composition includes (1) fluoroethylene carbonate (FEC), (2) vinylene carbonate (VC), (3) at least one ester (ES), and (4) a nitrile additive composition (NAC) which includes at least one nitrile compound. In some designs, a mole fraction of the NAC in the electrolyte is in a range of approximately 0.1 mol. % to approximately 2.0 mol. %. In some designs, a mole fraction of the at least one ES in the electrolyte is at least approximately 35 mol. %.

An electrolyte solution additive, an electrolyte solution including the same, and a lithium secondary battery including the same are disclosed herein. In some embodiments, an electrolyte solution additive includes a compound represented by Formula 1:

##STR00001##

Wherein X is oxygen (O) or sulfur (S), and R is a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms or N(R.sub.1).sub.2, wherein R.sub.1 is hydrogen or a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms. The additive has an excellent effect of scavenging a decomposition product generated from a lithium salt and simultaneously forming a robust film on a surface of a positive electrode.

An electrolyte solution additive, an electrolyte solution including the same, and a lithium secondary battery including the same are disclosed herein. In some embodiments, an electrolyte solution additive includes a compound represented by Formula 1:

##STR00001##

Wherein X is oxygen (O) or sulfur (S), and R is a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms or N(R.sub.1).sub.2, wherein R.sub.1 is hydrogen or a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms. The additive has an excellent effect of scavenging a decomposition product generated from a lithium salt and simultaneously forming a robust film on a surface of a positive electrode.

An electrolyte for use in an energy storage device, an energy storage device and a method of forming such electrolyte. The electrolyte includes a polymer matrix of at least two crosslinked structures, including a first polymeric material and a second polymeric material; and an electrolytic solution retained by the polymer matrix; wherein the electrolyte is arranged to physically deform when subjected to an external mechanical load applied to the polymer matrix.

An electrolyte for use in an energy storage device, an energy storage device and a method of forming such electrolyte. The electrolyte includes a polymer matrix of at least two crosslinked structures, including a first polymeric material and a second polymeric material; and an electrolytic solution retained by the polymer matrix; wherein the electrolyte is arranged to physically deform when subjected to an external mechanical load applied to the polymer matrix.

The invention relates to the technical field of secondary batteries, specifically to a high-temperature lithium secondary battery electrolyte and a battery cell. The high-temperature lithium secondary battery contains an additive composition consisting of a diisocyanate compound and a bicyclic sulfate compound.