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In order to cut the costs and overcome the leakage current of batteries caused in traditional method, this study introduces an improved voltage transfer method for lithium battery string management chip. This proposed circuit based on the improved voltage transfer method is fabricated in 180‐nm Bipolar‐CMOS‐DMOS is correct technology, and has been successfully applied to a three lithium batteries string management chip. These measurements indicate that this circuit transfers each cell’s voltage reliably and adopt protection against abnormal conditions. Furthermore, analysis of 50 samples shows that the improved method can greatly eliminate the battery leakage. The circuit reduces the leakage current to nanoampere scale and is integrated into the lithium battery string management chip, which is helpful for battery voltage balance and low cost.

In order to suppress leakage current caused in the traditional multi-cells series Li-ion battery pack protection system, a new battery voltage transfer method is presented in this paper, which uses the current generated in the transfer process of one of the batteries to compensate for the leakage of itself and other cells except the top cell. Based on the 0.18 µm Bipolar and CMOS and DMOS technology, this proposed circuit has been integrated into a 7-cells Li-ion battery charge and discharge protection chip successfully. The experimental results of cell balancing confirm that the balancing algorithm can help with the shortage of the voltage transfer circuit. Furthermore, analysis of 20 samples shows that the new method can greatly suppress the battery leakage. Compared with the traditional solution, the voltage transfer circuit proposed in this paper greatly reduces the leakage current, which helps to extend the service life of the battery.

Hydrogen (H

With the rapid development of renewable and sustainable energy, biogas upgrading for producing high-quality biomethane as an alternative to natural gas has attracted worldwide attention. This paper comprehensively reviews the current state of biogas upgrading technologies. The advances in physicochemical, photosynthetic autotrophic, and chemical autotrophic biogas upgrading technologies are briefly described with particular attention to the key challenges. New chemical autotrophic biogas upgrading strategies, such as direct and indirect exogenous hydrogen supply, for overcoming barriers to biogas upgrading and realizing highly efficient bioconversion of carbon dioxide are summarized. For each approach to exogenous hydrogen supply for biogas upgrading, the key findings and technical limitations are summarized and critically analyzed. Finally, future developments are also discussed to provide a reference for the development of biogas upgrading technology that can address the global energy crisis and climate change issues related to the application of biogas.

Biochar derived from residue cornstalk left after anaerobic bio-hydrogen production (RCA-biochar) was confirmed to enhance bio-hydrogen production from cornstalk hydrolysate. However, the role of RCA-biochar in simultaneous saccharification and fermentation (SSF) during bio-hydrogen production from cornstalk has not yet been revealed. This study therefore aims to fill this knowledge gap. It was observed that with the increase in RCA-biochar concentration from 0 g/L to 10.0 g/L, the maximal cumulative SSF bio-hydrogen yield varied from 24.3 ± 1.1 mL/g-substrate to 154.3 ± 3.6 mL/g substrate under varying pH values – 5.5, 6.0, 6.5, 7.0. The increasing bio-hydrogen production was observed to correlate with both RCA-biochar level and initial pH. Batch tests confirmed that the initial pH had an obvious effect an saccharification, while RCA-biochar affected anaerobic fermentation a lot. The findings revealed the role of previously unrecognized RCA-biochar in SSF bio-hydrogen production from cornstalk, which can provide an alternative approach for lignocellulosic bio-hydrogen production.