From 1 Sun to 10 Suns c‐Si Cells by Optimizing Metal Grid, Metal Resistance, and Junction Depth

Abstract

Use of a solar cell in concentrator PV technology requires reduction in its series resistance in order to minimize the resistive power losses. The present paper discusses a methodology of reducing the series resistance of a commercial c-Si solar cell for concentrator applications, in the range of 2 to 10 suns. Step by step optimization of commercial cell in terms of grid geometry, junction depth, and electroplating of the front metal contacts is proposed. A model of resistance network of solar cell is developed and used for the optimization. Efficiency of unoptimized commercial cell at 10 suns drops by 30% of its 1 sun value corresponding to resistive power loss of about 42%. The optimized cell with grid optimization, junction optimization, electroplating, and junction optimized with electroplated contacts cell gives resistive power loss of 20%, 16%, 11%, and 8%, respectively. An efficiency gain of 3% at 10 suns for fully optimized cell is estimated.

Selectivities of an all-wet-processed electrode film on ITO, ZnO, SiNx and doped Si for solar cell applications

“…Our wafers satisfied the conditions of high conductivity, low shadowing, low contact resistance, and minimal resistance loss. [18][19][20][21][22][23]. To assess the selective properties, we conducted a deposition experiment using a crystalline-shaped solar-cell wafer identical to the one shown in Fig.…”

PV‐GO: A multiobjective and robust optimization approach for the grid metallization design of Si‐based solar cells and modules

“…As a result, either both of them should be optimized at the same time or they can be combined into one single variable such as the fabrication cost or levelized cost of electricity (LCOE). , P c f c f LCOE ( cell = 1) ( mod = 1) ( cell = 1) ( mod = 1) [5][6][7] x x [8][9][10] x x x 9 x x x 9 x x x 5 x x x 5 x x 11 x x x 5,[12][13][14][15][16][17][18][19][20][21] x x 15,22,23 x x 15 x x 15 x x 15 x x 10,24 x x x 25 x x x 5,26 x x 5,27 x x x 28 x x…”

“…Furthermore,Equations 22,23,27,32,and 33 are applied so that the grid metallization design does not exceed the cell dimensions. Additionally,Equations 28,34,and 38 are defined to guarantee that the whole busbars and silver pads are covered by the interconnector ribbons (to maximize the contact area when soldering the interconnector ribbons during the fabrication of solar modules).Finally,Equations 20,21,25,26,30,31,36, and 37 assure that the obtained results are robust. Here, ′…”

A note on parameters of photovoltaic cells in dependence on irradiance and temperature

“…The problem of the series resistance influence on photovoltaic cell behaviour is usually discussed in an approach of changes I-V characteristics with series resistance at constant irradiance (e.g [1], [2], [3]). An influence of series resistance on the dependence of cell efficiency on irradiance have been discussed mainly in connection with concentrator photovoltaic [5] [6], even sometimes the effect of series resistance is practically neglected [7] and more attention is paid to effects connected with the cell temperature increase. This note is concentrated on influence of series resistance influence on the dependence of the cell efficiency on irradiance at lower irradiance level.…”