24.58% efficient commercial n‐type silicon solar cells with hydrogenation

Abstract

Tunnelling oxide passivated contact (TOPCon) solar cells are gaining significant commercial interest, due to the potential for high efficiency. Industrially, this passivated contact scheme is typically coupled with an n-type Czochralski (Cz) wafer. JinkoSolar Holding Co., Ltd. is one of the leading manufacturers that are producing n-type TOPCon solar cells (referred to as 'HOT' cells) on a commercial scale. In this work, the influence of a post-cell hydrogenation step, using illumination from an LED light source, on the performance and stability of n-type TOPCon solar cells is investigated.The incorporation of this additional hydrogenation treatment led to an average efficiency enhancement of 0.64% abs on a batch of 50 cells made in an industrial environment. This significant improvement was caused by a 6.9 mV and 1.04% abs increase in open-circuit voltage (V OC ) and fill factor (FF), respectively. We also assessed the stability and found almost no light-and elevated temperature-induced degradation (LeTID) in hydrogenated n-type TOPCon cells. Testing at 70 ± 5 C under 1-sun illumination revealed that the maximum degradation is limited to 0.06% rel .Following further stability testing, the efficiency increased beyond the initial value, up to 0.4% rel increase after 120 h. By incorporating this hydrogenation process into the production, an average line efficiency of 24.08% and V OC of 707.5 mV was achieved. The champion cell from the batch displayed an efficiency of 24.58%, as certified by measurement at the Chinese Academy of Sciences.

Large‐area monoPoly solar cells on 110 μm thin c–Si wafers with a rear n+poly‐Si/SiOx stack deposited by inline plasma‐enhanced chemical vapour deposition

“…The box and whiskers correspond to the 5th, 25th, 50th (median), 75th and 95th percentile of each split 718 mV achieved for this cell architecture. 33 When comparing the iV OC -to-V OC difference in this study (Figure 5), a larger drop of 12-15 mV is observed for the 150 Ω/sq emitter compared to an 8 mV drop for the 70 Ω/sq emitter. This is due to the expected increase in J 0 metal recombination (J 0metal ) to the lowly doped regions for the 150 Ω/sq emitter.…”

Flexible and Transparent Photovoltaic‐Based Broadband Photocommunication Window

“…[ 48–50 ] The Ga 2 O 3 and Cu 2 O heterojunction is known for generating high values of V oc owing to their suitable band alignment. [ 34,35 ] Ga 2 O 3 exhibited an improved offset of the conduction band with Cu 2 O compared with those obtained when layers of other oxides were used.…”

“…Commercialized Si solar cells can provide a high power output [ 35 ] and exhibit high absorption in the IR and visible regions. However, high‐energy UV photons cause heating, discoloration, delamination, and deterioration of the passivation layer of Si solar cells, because of which their PV performance deteriorates over time.…”

Design considerations for the bottom cell in perovskite/silicon tandems: a terawatt scalability perspective

“…56,57 Of these, only the combination of a thin silicon oxide coated with a heavily doped polysilicon layer has been intensely studied as a passivating contact for industrial silicon solar cells. 58,59 This passivation approach removes the need for a heavy diffusion in the following way. A tunnelling oxide on the wafer surface only allows one type of charge carrier to pass because there is a highly doped polycrystalline silicon layer behind, which pins the Fermi level to a band, which, in turn, is contacted by metal.…”