The invention discloses a high-
energy density lithium ion battery cell and a preparation method thereof. The
cell comprises a matrix layer, a composite positive
electrode layer, a composite diaphragm layer, a composite negative
electrode layer, an
isolation layer and an positive
electrode / negative electrode collector region, wherein a fast
lithium ion conductor is doped in the composite diaphragm layer, so that the
ion conductivity of the
cell is improved, better
thermal stability and puncture-resistant strength can be achieved, and the security of a battery can be improved; and the composite positive electrode / negative electrode
layers adopt a three-layer sandwich structure of an positive electrode / negative electrode activity layer, a conductive layer and an positive electrode / negative electrode activity layer in sequence, the conductive layer is formed by alternatively arranging conductive
fiber of carbon
fiber, carbon nanotubes and the like, so that not only can the
coating strength be enhanced so as to prevent the breakage of the
coating, but also the
conductivity of the
coating can be increased. According to high-
energy density lithium ion
battery cell and the preparation method thereof, the spraying technology, novel afflux technology and fast lithium ion conductor materials are simultaneously used and organically combined, so that the
energy density and the charging and discharging rate of the
cell can be greatly improved, the preparation cost can be greatly lowered, and the technique is simple and easy for industrialized production.