CN-121985626-A - Solar cell and preparation method thereof

Abstract

The invention relates to a solar cell and a preparation method thereof, the solar cell comprises a silicon substrate and a grid line electrode arranged on the silicon substrate, the grid line electrode comprises a main grid line and an auxiliary grid line, the surface of the silicon substrate comprises a grid line area and a non-grid line area, the grid line area is an area covered by the main grid line and the auxiliary grid line, the rest is the non-grid line area, the total area of the non-grid line area is A, A=NxDxL, N is the number of the auxiliary grid lines, D is the average distance between two adjacent auxiliary grid lines, and L is the average length of the auxiliary grid lines. According to the solar cell provided by the disclosure, the geometric layout of the auxiliary grid line is optimized on the premise of fixing the light shielding amount of the grid line by controlling the geometric layout relation between the total area of the non-grid line area and the auxiliary grid line, so that the solar cell has stronger current collection capability and lower series resistance, and the optical performance and the electrical performance of the solar cell are synergistically optimized.

Inventors

• MING LIN
• CHEN WEIKANG
• HAO LIANGJIE
• SONG XINXIN
• GUO XIAOPENG

Assignees

• 横店集团东磁股份有限公司

Dates

Publication Date

20260505

Application Date

20251212

Claims (10)

1. 1. The solar cell comprises a silicon substrate and a grid line electrode arranged on the silicon substrate, wherein the grid line electrode comprises a main grid line and an auxiliary grid line, the surface of the silicon substrate comprises a grid line area and a non-grid line area, the grid line area is an area covered by the main grid line and the auxiliary grid line, and the rest is the non-grid line area.
2. 2. The solar cell according to claim 1, wherein a ratio of a total area of the non-gate line region to a total area of the gate line region is 0.15 to 0.5.
3. 3. The solar cell according to claim 1, wherein a is 45cm 2 ~100cm 2 .
4. 4. The solar cell of claim 3, wherein N is 150 to 250; and/or D is 100-300 mu m; and/or L is 180-180.5 mm.
5. 5. The solar cell according to claim 1, wherein the sub-grid lines are arranged at equal intervals; and/or the auxiliary grid lines are arranged at equal lengths.
6. 6. The solar cell of claim 1, wherein D is inversely related to N.
7. 7. The solar cell of claim 1, wherein the total area of the non-gate line regions of the front side of the silicon-based substrate is a, and a = N x D x L.
8. 8. The solar cell of claim 1, wherein the front and back sides of the silicon-based substrate are each provided with a Poly layer.
9. 9. The method for manufacturing a solar cell according to any one of claims 1 to 8, wherein a number of sub-gate trenches having N, an average pitch D, and an average length L are formed in a silicon substrate during patterning, and n×d×l=a is satisfied, wherein a is a total area of a non-gate line region, and sub-gate lines are manufactured in the sub-gate trenches.
10. 10. The method for manufacturing a solar cell according to claim 9, wherein the sub-gate line groove is formed by laser grooving.

Description

Solar cell and preparation method thereof Technical Field The disclosure relates to the technical field of photovoltaics, in particular to a solar cell and a preparation method thereof. Background The solar cell is a core device in the field of photovoltaic power generation, and in many designs of the solar cell, the geometric layout of the grid line electrode is one of key factors influencing the optical performance and the electrical performance of the solar cell. However, conventional gate line designs face a fundamental technical dilemma, namely, the interplay between optical and electrical losses. In particular, in order to reduce the shielding of the gate electrode from incident light, it is desirable that the gate line is as thin and thin as possible to increase the light absorption area, however, in order to reduce the resistive loss of current transmitted to the electrode in the semiconductor substrate, it is also desirable that the gate line is as dense as possible to shorten the lateral transmission distance of carriers, so that these two requirements are inherently contradictory. Therefore, it is urgent to design a scheme capable of synergistically optimizing optical properties and electrical properties, thereby remarkably improving the photoelectric conversion efficiency of the solar cell. Disclosure of Invention Based on this, it is necessary to provide a solar cell and a method for manufacturing the same, which can realize the synergistic optimization of the optical performance and the electrical performance of the solar cell by controlling the geometric layout relationship between the total area of the non-grid line region and the sub-grid line. The invention provides a solar cell, which comprises a silicon-based substrate and a grid line electrode arranged on the silicon-based substrate, wherein the grid line electrode comprises a main grid line and a secondary grid line, the surface of the silicon-based substrate comprises a grid line area and a non-grid line area, the grid line area is an area covered by the main grid line and the secondary grid line, and the rest is the non-grid line area; the total area of the non-grid line area is A, wherein A=N×D×L, N is the number of the auxiliary grid lines, D is the average distance between two adjacent auxiliary grid lines, and L is the average length of the auxiliary grid lines. In one embodiment, the ratio of the total area of the non-gate line region to the total area of the gate line region is 0.15-0.5. The total area ratio of the non-grid line area is set in an optimization range, so that the cooperative optimization of the optical performance and the electrical performance of the solar cell is facilitated. In one embodiment, the A is 45cm 2~100cm2. In one embodiment, the number N is 150 to 250; and/or D is 100-300 mu m; and/or L is 180-180.5 mm. Through the optimization design of the parameters, the total area of the non-grid line area is set to be in an optimization range and constant, and through accurately regulating and controlling the geometric layout of the auxiliary grid lines, the conversion efficiency and the filling factor of the solar cell are improved synchronously, and the cooperative optimization of the overall performance of the solar cell is realized. In one embodiment, the auxiliary grid lines are arranged at equal intervals; and/or the auxiliary grid lines are arranged at equal lengths. The equidistant and/or equal-length arrangement is beneficial to balancing the optical loss and the electrical loss of the solar cell, so that the optical loss and the electrical loss of the solar cell are further reduced integrally, and the photoelectric conversion efficiency of the solar cell is further improved. In one embodiment, the D is inversely related to the N. The photoelectric conversion efficiency of the solar cell is further improved by reducing the distance between two adjacent auxiliary grid lines and increasing the number of the auxiliary grid lines. In one embodiment, the total area of the non-gate line regions on the front surface of the silicon substrate is a, and a=n×d×l. The solar cell is beneficial to achieving stronger current collection capability and lower series resistance. In one embodiment, the front and back sides of the silicon-based substrate are provided with Poly layers. And the cooperative optimization of the overall performance of the solar cell is facilitated. The present disclosure also provides a method for manufacturing a solar cell as described above, in which, in the patterning process, a number of sub-gate trenches having N, an average pitch of D, and an average length of L are opened on a silicon substrate, and n×d×l=a is satisfied, where a is a total area of a non-gate line region, and sub-gate lines are manufactured in the sub-gate trenches. In one embodiment, the auxiliary gate slot is formed by laser grooving. According to the solar cell, the total area of the non-grid line area and the geometri