In this paper, we present EV-Eye, a first-of-its-kind large-scale multimodal eye tracking dataset aimed at inspiring research on high-frequency eye/gaze tracking. EV-Eye utilizes the emerging bio-inspired event camera to capture independent pixel-level intensity changes induced by eye movements, achieving sub-microsecond latency. Our dataset was curated over two weeks and collected from 48 participants encompassing diverse genders and age groups. It comprises over 1.5 million near-eye grayscale images and 2.7 billion event samples generated by two DAVIS346 event cameras. Additionally, the dataset contains 675 thousand scene images and 2.7 million gaze references captured by a Tobii Pro Glasses 3 eye tracker for cross-modality validation. Compared with existing event-based high-frequency eye tracking datasets, our dataset is significantly larger in size, and the gaze references involve more natural and diverse eye movement patterns, i.e., fixation, saccade, and smooth pursuit. Alongside the event data, we also present a hybrid eye tracking method as a benchmark, which leverages both the near-eye grayscale images and event data for robust and high-frequency eye tracking. We show that our method achieves higher accuracy for both pupil and gaze estimation tasks compared to the existing solution.

The EU crystalline silicon (c-Si) PV manufacturing industry has faced strong foreign competition in the last decade. To strive in this competitive environment and differentiate itself from the competition, the EU c-Si PV manufacturing industry needs to (1) focus on highly performing c-Si PV technologies, (2) include sustainability by design, and (3) develop differentiated PV module designs for a broad range of PV applications to tap into rapidly growing existing and new markets. This is precisely the aim of the 3.5 years long H2020 funded HighLite project, which started in October 2019 under the work program LC-SC3-RES-15-2019: Increase the competitiveness of the EU PV manufacturing industry. To achieve this goal, the HighLite project focuses on bringing two advanced PV module designs and the related manufacturing solutions to higher technology readiness levels (TRL). The first module design aims to combine the benefits of n-type silicon heterojunction (SHJ) cells (high efficiency and bifaciality potential, improved sustainability, rapidly growing supply chain in the EU) with the ones of shingle assembly (higher packing density, improved modularity, and excellent aesthetics). The second module design is based on the assembly of low-cost industrial interdigitated back-contact (IBC) cells cut in half or smaller, which is interesting to improve module efficiencies and increase modularity (key for application in buildings, vehicles, etc.). This contribution provides an overview of the key results achieved so far by the HighLite project partners and discusses their relevance to help raise the EU PV industries' competitiveness. We report on promising high-efficiency industrial cell results (24.1% SHJ cell with a shingle layout and 23.9% IBC cell with passivated contacts), novel approaches for high-throughput laser cutting and edge re-passivation, module designs for BAPV, BIPV, and VIPV applications passing extended testing, and first 1-year outdoor monitoring results compared with benchmark products.

The high usage of silver in industrial solar cells may limit the growth of the solar industry. One solution is to replace Ag with copper. A screen printable Cu paste is used herein to metallize industrial interdigitated back contact (IBC) solar cells. A novel metallization structure is proposed for making solar cells. Cu paste is applied to replace the majority of the Ag used in IBC cells as busbars and fingers. Cu paste is evaluated for use as fingers, and solar cells are made to test conversion efficiency and reliability. The Cu paste achieves comparably low resistivity, and Cu paste printed cells demonstrate similar efficiency to Ag paste printed cells, with an average efficiency of 23%, and only 4.5 mg W⁻¹ of Ag usage. Also, the solar cells are stable and no Cu in-diffusion is observed under damp heat (85 °C, 85% relative humidity) and thermal stress (200 °C) for 1000 h, respectively. All processes used in this study can be carried out with industrial equipment. These findings reveal a new application for Cu pastes and point to a new direction for reducing Ag utilization and cost.

The edge recombination losses of crystalline silicon solar cells become significant when they are cut into smaller pieces to be assembled into modules. With the interdigitated pattern of doped p and n regions on the rear side, the interdigitated back contact (IBC) solar cells can be cut through different doped regions. In this study, the cutting losses in IBC solar cells are investigated and various cutting scenarios are studied. Through simulations and experimental measurements, it is found that the cut losses can be reduced by cutting through the back surface field rather than through the emitter. The losses under low light intensity are reduced to an even greater extent. When a 23% cell is cut into 1/3 pieces, the efficiency can be increased by 1.2%rel (cut related losses were improved from 2.0rel to 0.8%rel under standard 1-sun testing conditions, compared to cutting through the emitter. Under low light intensity of 0.25 sun, the improvement is around 2.4%rel. The improvement is mainly due to lower FF losses in the I-V characteristics, and this is further confirmed by Suns-Voc and PL measurements. In the pFF analysis, the additional losses due to laser damage are also observed. This strategy of cutting through the BSF region in IBC solar cells can be quickly adopted in mass production without the need for additional processes or equipment and both module power and energy yield can be increased.