Silicon heterojunction solar cells: Recent technological development and practical aspects - from lab to industry

Abstract

We review the recent progress of silicon heterojunction (SHJ) solar cells. Recently, a new efficiency world record for silicon solar cells of 26.7% has been set by Kaneka Corp. using this technology. This was mainly achieved by remarkably increasing the fill-factor (FF) to 84.9%-the highest FF published for a silicon solar cell to date. High FF have for long been a challenge for SHJ technology. We emphasize with the help of simulations the importance of minimised recombination, not only to reach high open-circuit voltages, but also high FF, and discuss the most important loss mechanisms. We review the different cell-to-module loss and gain mechanisms putting focus on those that impact FF. With respect to industrialization of SHJ technology, we discuss the current hindrances and possible solutions, of which many are already present in industry. With the intrinsic bifacial nature of SHJ technology as well as its low temperature coefficient record high energy production per rated power is achievable in many climate regions. 83.8%. This high FF was enabled by a series resistance of only 0.32 Ω cm 2 , demonstrating that very low-resistive contacts can be achieved also with SHJ contacts. Later in 2017, further progress in efficiency was reported, culminating at 26.7% [4]. This cell featured an

Potential of very thin and high‐efficiency silicon heterojunction solar cells

“…Next, we consider the iFF dependence on w. In general, the iFF is known to be more sensitive to surface and bulk SRH recombination (ie, N S and τ SHR, bulk ) than the iV OC , because SRH recombination dominates the total recombination at the maximum power point where Δn is much smaller than that under the open-circuit condition. 8,28,41 This trend can be also confirmed in our simulation. Figure 8C,D shows the iFF as a function of w when limited by the surface and the bulk recombination, respectively.…”

“…In the following, we briefly describe the basic formulae for simulating iV OC and iFF of SHJ solar cells. Similar approaches were already reported by Augusto et al and Haschke et al…”

Dual‐Function Light‐Trapping: Selective Plating Mask of SiOx/SiNx Stacks for Silicon Heterojunction Solar Cells

“…Higher photoelectric conversion efficiency and lower production cost are the main objectives for the development of photovoltaic (PV) industry. Among the varieties of silicon solar cell technologies, silicon heterojunction (SHJ) solar cell can play a significant role in PV market due to its high open circuit voltage ( V oc = 750 mV), high fill factor (FF = 84.6%), low process energy consumption, and improved temperature coefficient . However, bifacial SHJ solar cell suffers from relatively low short circuit current density ( J sc ) and high series resistance.…”

“…Among the varieties of silicon solar cell technologies, silicon heterojunction (SHJ) solar cell can play a significant role in PV market due to its high open circuit voltage (V oc ¼ 750 mV), high fill factor (FF ¼ 84.6%), low process energy consumption, and improved temperature coefficient. [1][2][3][4][5] However, bifacial SHJ solar cell suffers from relatively low short circuit current density (J sc ) and high series resistance. These could be ascribed to several causes, including parasitic absorption of doped amorphous silicon and transparent conductive oxide (TCO) film, [6] inter-band optical absorption, and reflection loss of anti-reflective TCO coating, [7] high resistivity of low temperature silver paste.…”

Monolithic Perovskite/Si Tandem Solar Cells: Pathways to Over 30% Efficiency

“…In parallel, Si-based heterojunction solar cells (HJTs) have undergone substantial development and represent a promising next step beyond PERC, a record low temperature coefficient and high energy yield, as well as thinner wafers for lower material. [7] HJT is progressively gaining momentum and will possibly earn as much as a 10% market share within the next decade. By combining the HJT technology with an interdigitated back contact (IBC) design, an efficiency of 26.7% marked the most recent world record for silicon solar cells, breaking the long-lasting record based on the PERL design (passivated emitter and rear locally diffused), a variation of PERC.…”