Back-passivation solar cell

The utility model provides a back-passivation solar cell, comprising a front-electrode main grid, a front-electrode fine grid, a front antireflection film, a P-type silicon sheet with PN junction, an aluminum back-surface field and a back electrode welding leads. A back-passivation layer is added between a back surface of the silicon sheet and the aluminum back-surface field. Local positions of the back-passivation layer realize conduction of the back surface of the silicon sheet and the aluminum back-surface field by silver, silver aluminum or aluminum. The back-passivation solar cell provided by the utility model reduces recombination rate of a contact interface between silicon and aluminum metal and raises a battery electrical performance, there greatly raising battery conversion efficiency. The battery conversion efficiency can be raised by 0.4-1.0%.