Solar battery

Abstract

Disclosed is a solar-energy battery including a substrate, a dielectric layer, at least one through hole arranged in the dielectric layer, an electrode arranged on the dielectric layer, an opening, a first area and a second area. The electrode includes a first structure provided with a first conductive section and a second structure arranged in the through hole. The opening is arranged in the dielectric layer and is surrounded by the electrode, wherein the conductive section is arranged in the opening. The first area is a total area of an orthographic projection of the opening on the substrate. The second area, which is larger than the first area, is a total area of an orthographic projection of the electrode on the substrate. The electrode of the solar-energy battery is capable of restraining diffusion of a substrate material so that enough substrate material can be mixed with an electrode material to form a local back surface field with a high thickness and good quality. Therefore, conversion efficiency of the battery is improved.

Description

technical field [0001] The invention relates to a solar cell, in particular to a silicon crystal solar cell with a local back electric field structure. Background technique [0002] refer to figure 1 , is a known solar cell, mainly comprising: a substrate 11, an emitter layer 12 forming a p-n junction with the substrate 11, a dielectric layer 13, and a plurality of back electric field structures formed on local parts of the substrate 11 (local back surface field, LBSF for short) 14 and a back electrode 15 . [0003] The dielectric layer 13 is formed on a back surface 111 of the substrate 11 and has a plurality of circular through holes 131 spaced from front to back, left to right. The back electric field structure 14 is formed on the back surface 111 corresponding to the through hole 131 , and the carrier concentration of the back electric field structure 14 is higher than that of the p-type substrate, which can help improve carrier collection efficiency and photoelectric ...

AI Technical Summary

Problems solved by technology

[0008] Although Figure 5 , Image 6 The improved structure helps to reduce the cavity ratio of the linear through-hole battery, but if blindly reducing the area occupied by the back electrode 15 to limit the diffusion of silicon, the area of ​​the back electrode 15 will be too small, which will lead to The electrode conductivity is not good, the series resistance of the battery is too high, and in Figure 5 , Image 6 In this case, the current between two adjacent conductive segments 157 cannot be directly transmitted, but can only be conducted to the main grid line 153 through the conductive segments 157, so the current transmission is limited and the conductivity is poor.

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