An anode for a magnesium battery, including a core element made from a core material, wherein a magnesium coating is at least partially arranged on a surface of the core element, a protective layer being arranged on a surface of the magnesium coating. A method for producing such an anode and a magnesium battery having at least one such anode are also provided.

Novel, rechargeable magnesium/magnesium sulfide batteries are disclosed therein, having energy density competitive with lithium batteries, high cycle life, and lower cost. Production method of stabilized MgS is also described, as well as various cells constructions.

Novel, rechargeable magnesium/magnesium sulfide batteries are disclosed therein, having energy density competitive with lithium batteries, high cycle life, and lower cost. Production method of stabilized MgS is also described, as well as various cells constructions.

The nickel-containing hydroxide particle covered with cobalt, wherein in a volume-based particle size distribution, the nickel-containing hydroxide particle covered with cobalt has the maximum peak with a height a, one peak at a height of (½)a or higher, and has a value A of formula (1) calculated from a width b of the maximum peak at a height of (½)a, and in a volume-based particle size distribution after compression treatment, the nickel-containing hydroxide particle covered with cobalt has the maximum peak with a height c, and has a value B of formula (2) calculated from a width d of the maximum peak at a height of (½)c, and wherein the value B and the value A have a relation represented by formula (3):

A=[(b×(½)a]/2  (1)

B=[(d×(½)c]/2  (2)

−1.50≤[(B−A)/A]×1005.00  (3)

The nickel-containing hydroxide particle covered with cobalt, wherein in a volume-based particle size distribution, the nickel-containing hydroxide particle covered with cobalt has the maximum peak with a height a, one peak at a height of (½)a or higher, and has a value A of formula (1) calculated from a width b of the maximum peak at a height of (½)a, and in a volume-based particle size distribution after compression treatment, the nickel-containing hydroxide particle covered with cobalt has the maximum peak with a height c, and has a value B of formula (2) calculated from a width d of the maximum peak at a height of (½)c, and wherein the value B and the value A have a relation represented by formula (3):

A=[(b×(½)a]/2  (1)

B=[(d×(½)c]/2  (2)

−1.50≤[(B−A)/A]×1005.00  (3)

Provided is an electrochemical device including a negative electrode, a positive electrode, and a separator disposed between the negative electrode and the positive electrode. In the electrochemical device, the negative electrode is an electrode containing magnesium, and is in contact with a fullerene analogue-containing layer containing a fullerene analogue. The electrolytic solution of the electrochemical device includes a solvent and a magnesium salt contained in the solvent.

Provided is an electrochemical device including a negative electrode, a positive electrode, and a separator disposed between the negative electrode and the positive electrode. In the electrochemical device, the negative electrode is an electrode containing magnesium, and is in contact with a fullerene analogue-containing layer containing a fullerene analogue. The electrolytic solution of the electrochemical device includes a solvent and a magnesium salt contained in the solvent.

The present disclosure discloses a capacity-compensation electrolyte additive and electrolyte having the same, the additive comprises one or more of Li.sub.xP.sub.y, Na.sub.mP.sub.n and K.sub.pP.sub.q, where 0<x≤3, 0<y≤11, 0<m≤3, 0<n≤11, 0<p≤3 and 0<q≤11, the electrolyte is applied to a lithium-ion battery, a sodium-ion battery or a potassium-ion battery. The additive can decompose active ions and electrons during whole charge-discharge cycle, and improves the initial Coulombic efficiency of the battery, specific capacity and cycling stability, so as to achieve uniform capacity compensation; and the additive is dissolved prior to electrolyte solvents, the products stabilize both of cathode and anode solid electrolyte layer, and improve capacity retention ratio in batteries so as to achieve stable cycling. Adding additive in electrolyte will not hazard electrode structure, can achieve uniform capacity compensation, has higher safety and easy to implement.

The present disclosure discloses a capacity-compensation electrolyte additive and electrolyte having the same, the additive comprises one or more of Li.sub.xP.sub.y, Na.sub.mP.sub.n and K.sub.pP.sub.q, where 0<x≤3, 0<y≤11, 0<m≤3, 0<n≤11, 0<p≤3 and 0<q≤11, the electrolyte is applied to a lithium-ion battery, a sodium-ion battery or a potassium-ion battery. The additive can decompose active ions and electrons during whole charge-discharge cycle, and improves the initial Coulombic efficiency of the battery, specific capacity and cycling stability, so as to achieve uniform capacity compensation; and the additive is dissolved prior to electrolyte solvents, the products stabilize both of cathode and anode solid electrolyte layer, and improve capacity retention ratio in batteries so as to achieve stable cycling. Adding additive in electrolyte will not hazard electrode structure, can achieve uniform capacity compensation, has higher safety and easy to implement.

The present disclosure discloses a capacity-compensation electrolyte, comprising: an organic solvent, an electrolyte salt and an electrolyte additive capable of compensating ions and electrons simultaneously; wherein the electrolyte additive comprises: a component capable of compensating ions and electrons simultaneously, or a composition of a component capable of compensating ions and a component capable of compensating electrons; the component capable of compensating ions and electrons simultaneously refers to a component capable of decomposing and releasing active ions and electrons simultaneously in the electrolyte during the working process of the battery; the component capable of compensation ions refers to a component capable of decomposing and releasing active ions in the electrolyte during the working process of the battery solution; and the component capable of compensation electrons refers to a component capable of decomposing and releasing electrons in the electrolyte during the working process of the battery solution.