Progress in Electrolyte Engineering of Aqueous Batteries in a Wide Temperature Range

Aqueous rechargeable batteries are safe and environmentally friendly and can be made at a low cost;as such,they are attracting attention in the field of energy storage.However,the temperature sensitivity of aqueous batteries hinders their practical application.The solvent water freezes at low temperatures,and there is a reduction in ionic conductivity,whereas it evaporates rapidly at high temperatures,which causes increased side reactions.This review discusses recent progress in improving the performance of aqueous batteries,mainly with respect to electrolyte engineering and the associated strategies employed to achieve such improvements over a wide temperature domain.The review focuses on fi ve electrolyte engineer-ing(aqueous high-concentration electrolytes,organic electrolytes,quasi-solid/solid electrolytes,hybrid electrolytes,and eutectic electrolytes)and investigates the mechanisms involved in reducing the solidifi cation point and boiling point of the electrolyte and enhancing the extreme-temperature electrochemical performance.Finally,the prospect of further improving the wide temperature range performance of aqueous rechargeable batteries is presented.

退役动力电池回收利用的现状及碳核算研究进展

新能源汽车行业的蓬勃发展促使动力电池报废量大幅上涨,产生数量庞大的固体废物。通过梯次利用和回收再生对退役动力电池进行再利用不仅能够实现有价金属的资源化再利用,还可降低碳排放和生产成本,是推进循环经济发展和资源集约利用的关键环节,对于落实“双碳”战略和推进生态文明建设具有重要意义。目前,研究领域内已发布大量与退役电池相关的文献和资讯,汇总行业关键信息,为业内人员提供参考十分有必要。为此,本综述立足行业现状,讨论了退役动力电池不同回收利用方式对环境和经济的影响,同时,分析回收利用现状并归纳研究进展,提出退役动力电池碳排放核算方法,指出回收的必要性和可行性,为建设无废城市和实现“双碳”目标提供借鉴。希望电池回收行业未来能够在国家的宏观调控下,结合高效绿色的回收技术和相关标准规范实现健康有序发展。要点:(1)退役电池回收再生能够有效实现资源循环利用并减少碳排放。(2)不同电池再生方式产生的环境影响和经济效益各异。(3)退役动力电池碳核算是助力“双碳”目标实现的重要方式。

Alkyl-thiophene-alkyl linkers to construct double-cable conjugated polymers for single-component organic solar cells

In this work,semirigid linkers of the alkyl-thiophene-alkyl structure are developed to construct double-cable polymers.Three alkyl units,propyl(C3H6),hexyl(C6H12),and dodecyl(C12H24),are applied as semirigid linkers,yielding three double-cable polymers:PBC6-T,PBC12-T,and PBC24-T,respectively.PBC12-T which uses C6H12-thiophene-C6H12 linkers is found to exhibit the best device efficiency of 5.56%,while PBC6-T and PBC24-T with shorter or longer linkers yield device efficiencies of only 2.65%and 1.09%in single-component organic solar cells(SCOSCs).Further studies reveal that PBC12-T exhibits higher crystallinity and improved charge transport,resulting in better efficiencies.Our work provides an approach to construct double-cable conjugated polymers with long alkyl linkers,and it shows the importance of the linker length for the photovoltaic performance of SCOSCs.

High-Performance D-A Copolymer Donor Based on Difluoroquinoxaline A-Unit with Alkyl-Chlorothiophene Substituents for Polymer Solar Cells

Side chain engineering with fluorine substitution is widely used to enhance photovoltaic performance of polymer donors in the research field of polymer solar cells(PSCs).However,fluorine substitution has disadvantages of complicated synthesis and high cost.Herein,we synthesized a novel D-A copolymer donor PBQ9 based on difluoroquinoxaline A-unit with chlorine substitution on its alkyl-thiophene side chains instead of fluorine substitution in the polymer donor PBQ6,which greatly shortens the synthetic route and reduces the cost.Interestingly,the optimized binary PSC with PBQ9 as polymer donor and m-TEH as acceptor demonstrated a high power conversion efficiency(PCE)of 18.81%(certified PCE of 18.33%by National Institute of Metrology,China)with a high fill factor of 80.59%,and the photovoltaic performance of the PSCs is insensitive to the different batches of the polymer donor.The results indicate that PBQ9 is a high-performance polymer donor and that chlorine substitution is an effective strategy to improve photovoltaic performance and reduce the cost of polymer donors.

Chlorinated polymerized small molecule acceptor enabling ternary all-polymer solar cells with over 16.6% efficiency

Recently,all-polymer solar cells(all-PSCs) based on polymerized small molecule acceptors(PSMAs) have achieved significant progress.Ternary blending has proven to be an effective strategy to further boost the power conversion efficiency(PCE) of the all-PSCs.Herein,a new A-DA′D-A small-molecule acceptor-based PSMA(named as PYCl-T) was designed and synthesized,which possesses similar polymer backbone with the widely used PY-IT,but with chlorine substitution on the A-end groups in the A-DA′D-A structure.PYCl-T was then employed as the third component into the PM6:PY-IT system and the ternary all-PSCs based on PM6:PY-IT:PYCl-T demonstrated a high PCE of 16.62%(certified value of 16.3%).Moreover,the PCE of 15.52% was realized in the enlarged ternary all-PSCs with effective area of 1 cm^(2),indicating the great potential in large-scale applications.Moreover,the optimized ternary blend films of PM6:PY-IT:PYCl-T show excellent thermal stability at 150 ℃.This work demonstrates that the utilization of a ternary blend system involving two well-compatible PSMA polymer acceptors is an effective strategy to boost the performance of the all-PSCs.

Stable perovskite solar cells with efficiency of 22.6%via quinoxaline-based polymeric hole transport material

Poor stability of spiro-OMe TAD hole transport materials(HTMs)with dopant is a major obstacle for the commercialization of perovskite solar cells(pero-SCs).Herein,we demonstrate a series of quinoxaline-based D-A copolymers PBQ5,PBQ6 and PBQ10 as the dopant-free polymer HTMs for high performance pero-SCs.The D-A copolymers are composed of fluorothienyl benzodithiophene(BDTT)as D-unit,difluoroquinoxaline(DFQ)with different side chains as A-unit,and thiophene asπ-bridge,where the side chains on the DFQ unit are bi-alkyl for PBQ5,bi-alkyl-fluorothienyl for PBQ6,and alkoxyl for PBQ10.All the three copolymers are adopted as the dopant-free HTM in the pero-SCs.The planar n-i-p structured pero-SCs based on(FAPb I_(3))_(0.98)(MAPb Br_(3))_(0.02)with PBQ6 HTM demonstrated the high power conversion efficiency(PCE)of 22.6%with Vocof1.13 V and FF of 80.8%,which is benefitted from the suitable energy level and high hole mobility of PBQ6.The PCE of 22.6%is the highest efficiency reported in the n-i-p structured pero-SCs based on dopant-free D-A copolymer HTM.In addition,the peroSCs show significantly enhanced ambient,thermal and light-soaking stability compared with the devices with traditional spiroOMe TAD HTM.

辛基取代喹喔啉聚合物给体使全聚合物有机太阳能电池的效率超过17%

本文设计并合成了一种新型喹喔啉类聚合物给体PBQ8,其在喹喔啉单元上具有正辛基侧链,与先前报道的PBQ5(异辛基侧链)具有相同的聚合物骨架结构.与PBQ5相比,PBQ8表现出更强的分子间相互作用和更好的分子堆积.当其与聚合物受体PY-IT共混时,基于PBQ8:PY-IT的全聚合物太阳能电池表现出远高于PBQ5:PY-IT器件效率,其能量转化效率为17.04%,这是目前全聚合物太阳能电池中的最高效率之一.结果表明,聚合物给体的侧链工程是进一步提高全聚合物太阳能电池光伏性能的有效途径.

Non-equivalent D-A copolymerization strategy towards highly efficient polymer donor for polymer solar cells

D-A copolymerization is a broadly utilized molecular design strategy to construct high efficiency photovoltaic materials for polymer solar cells(PSCs),and all the D-A copolymer donors reported till now are the alternate D-A copolymers with equal D-and A-units.Here,we first propose a non-equivalent D-A copolymerization strategy with unequal D-and A-units,and develop three novel non-equivalent D-A copolymer donors(PM6-D1,PM6-D2 and PM6-D3 with D/A unit ratio of 1.1:0.9,1.2:0.8 and1.3:0.7,respectively)by inserting more D units into the alternate D-A copolymer PM6 backbone to finely tune the physicochemical and photovoltaic properties of the polymers.The three non-equivalent D-A copolymers show the down-shifted highest occupied molecular orbital(HOMO)energy levels,higher hole mobility,higher degree of molecular self-assembly and higher molecular crystallinity with the increase of D-unit ratio in comparison with the alternate D-A copolymer PM6.As a result,all the three non-equivalent D-A copolymer-based PSCs with Y6 as acceptor achieve improved power conversion efficiency(PCE)with higher V_(oc),larger J_(sc)and higher FF simultaneously.Particularly,the PM6-D1:Y6 based PSC achieved a high PCE of17.71%,which is significantly higher than that(15.82%)of the PM6:Y6 based PSC and is one of the highest performances in the binary PSCs.