In the scope of developing new electrochemical concepts to build batteries with high energy density,chloride ion batteries(CIBs)have emerged as a candidate for the next generation of novel electrochemical energy stora...In the scope of developing new electrochemical concepts to build batteries with high energy density,chloride ion batteries(CIBs)have emerged as a candidate for the next generation of novel electrochemical energy storage technologies,which show the potential in matching or even surpassing the current lithium metal batteries in terms of energy density,dendrite-free safety,and elimination of the dependence on the strained lithium and cobalt resources.However,the development of CIBs is still at the initial stage with unsatisfactory performance and several challenges have hindered them from reaching commercialization.In this review,we examine the current advances of CIBs by considering the electrode material design to the electrolyte,thus outlining the new opportunities of aqueous CIBs especially combined with desalination,chloride redox battery,etc.With respect to the developing road of lithium ion and fluoride ion batteries,the possibility of using solid-state chloride ion conductors to replace liquid electrolytes is tentatively discussed.Going beyond,perspectives and clear suggestions are concluded by highlighting the major obstacles and by prescribing specific research topics to inspire more efforts for CIBs in large-scale energy storage applications.展开更多
Chloride solid electrolytes possess multiple advantages for the construction of safe,energy-dense allsolid-state sodium batteries,but presently the chlorides with sufficiently high cost-competitiveness for commerciali...Chloride solid electrolytes possess multiple advantages for the construction of safe,energy-dense allsolid-state sodium batteries,but presently the chlorides with sufficiently high cost-competitiveness for commercialization almost all exhibit low Na-ion conductivities of around 10^(-5)S cm^(-1)or lower.Here,we report a chloride solid electrolyte,Na_(2.7)ZFCl_(5.3)O_(0.7),which reaches a Na-ion conductivity of 2.29×10^(-4)S cm^(-1)at 25℃without involving overly expensive raw materials such as rare-earth chlorides or Na_(2)S.In addition to the efficient ion transport,Na_(2.7)ZrCl_(5.3)O_(0.7)also shows an excellent deformability surpassing that of the widely studied Na_(3)PS_(4),Na_(3)SbS_(4),and Na_(2)ZrCl_(6)solid electrolytes.The combination of these advantages allows the all-solid-state cell based on Na_(2.7)ZrCl_(5.3)O_(0.7)and NaCrO_(2)to realize stable room-temperature cycling at a much higher specific current than those based on other non-viscoelastic chloride solid electrolytes in literature(120 mA g^(-1)vs.12-55 mA g^(-1));after 100 cycles at such a high rate,the Na_(2.7)ZFCl_(5.3)O_(0.7)-based cell can still deliver a discharge capacity of 80 mAh g^(-1)at25℃.展开更多
The reductant is a critical factor in the hydrometallurgical recycling of valuable metals from spent lithium-ion batteries(LIBs).There is limited information regarding the use of SnCl_(2) as a reductant with organic a...The reductant is a critical factor in the hydrometallurgical recycling of valuable metals from spent lithium-ion batteries(LIBs).There is limited information regarding the use of SnCl_(2) as a reductant with organic acid(maleic acid)for recovering valuable metals from spent Li-CoO_(2) material.In this study,the leaching efficiencies of Li and Co with 1 mol·L^(−1) of maleic acid and 0.3 mol·L^(−1) of SnCl_(2) were found to be 98.67%and 97.5%,respectively,at 60°C and a reaction time of 40 min.We investigated the kinetics and thermodynamics of the leaching process in this study to better understand the mechanism of the leaching process.Based on a comparison with H_(2)O_(2) with respect to leaching efficiency,the optimal leaching parameters,and the activation energy,we determined that it is feasible to replace H_(2)O_(2) with SnCl_(2) as a leaching reductant in the leaching process.In addition,when SnCl_(2) is used in the acid-leaching process,Sn residue in the leachate may have a positive effect on the re-synthesis of nickel-rich cathode materials.Therefore,the results of this study provide a potential direction for the selection of reductants in the hydrometallurgical recovery of valuable metals from spent LIBs.展开更多
Aqueous zinc ion batteries have high potential applicability for energy storage due to their reliable safety,environmental friendliness,and low cost.However,the freezing of aqueous electrolytes limits the normal opera...Aqueous zinc ion batteries have high potential applicability for energy storage due to their reliable safety,environmental friendliness,and low cost.However,the freezing of aqueous electrolytes limits the normal operation of batteries at low temperatures.Herein,a series of high-performance and low-cost chloride hydrogel electrolytes with high concentrations and low freezing points are developed.The electrochemical windows of the chloride hydrogel electrolytes are enlarged by>1 V under cryogenic conditions due to the obvious evolution of hydrogen bonds,which highly facilitates the operation of electrolytes at ultralow temperatures,as evidenced by the low-temperature Raman spectroscopy and linear scanning voltammetry.Based on the Hofmeister effect,the hydrogen-bond network of the cooperative chloride hydrogel electrolyte comprising 3 M ZnCl_(2)and 6 M LiCl can be strongly interrupted,thus exhibiting a sufficient ionic conductivity of 1.14 mS cm;and a low activation energy of 0.21 e V at-50℃.This superior electrolyte endows a polyaniline/Zn battery with a remarkable discharge specific capacity of 96.5 mAh g;at-50℃,while the capacity retention remains~100%after 2000 cycles.These results will broaden the basic understanding of chloride hydrogel electrolytes and provide new insights into the development of ultralow-temperature aqueous batteries.展开更多
LiNi0.8Co0.1Mn0.1O2 was prepared by a chloride co-precipitation method and characterized by thermogravimetric analysis, X-ray diffractometry with Rietveld refinement,electron scanning microscopy and electrochemical me...LiNi0.8Co0.1Mn0.1O2 was prepared by a chloride co-precipitation method and characterized by thermogravimetric analysis, X-ray diffractometry with Rietveld refinement,electron scanning microscopy and electrochemical measurements.Effects of lithium ion content and sintering temperature on physical and electrochemical performance of LiNi0.8Co0.1Mn0.1O2 were also investigated. The results show that the sample synthesized at 750℃with 105%lithium content has fine particle sizes around 200 nm and homogenous sizes distribution.The initial discharge capacity for the powder is 184 mA·h/g between 2.7 and 4.3 V at 0.1C and room temperature.展开更多
金属氯化物-石墨插层化合物具有导电性优异,石墨层间距大等特点,可用作钠离子电池负极材料。然而,在传统金属氯化物插层石墨过程中,不可避免地用到氯气,既增加了实验操作的风险,也对实验设备提出更高要求。基于上述原因,本文创新性地使...金属氯化物-石墨插层化合物具有导电性优异,石墨层间距大等特点,可用作钠离子电池负极材料。然而,在传统金属氯化物插层石墨过程中,不可避免地用到氯气,既增加了实验操作的风险,也对实验设备提出更高要求。基于上述原因,本文创新性地使用SO_(2)Cl_(2)作为氯源来促进BiCl_(3)插层石墨。该方法不仅有效提高了BiCl_(3)插层效率,也避免了直接使用氯气带来的安全性风险。采用该方法所合成的三氯化铋-石墨插层化合物(BiCl_(3)-GICs)的层间距为1.26 nm,BiCl_(3)插层含量高达42%。以其为负极材料,组装的钠离子电池具有高的比容量(213 mAh g^(-1)at 1 A g^(-1))和优异的倍率性能(170 mAh g^(-1)at 5 A g^(-1))。此外,原位拉曼光谱测试结果表明,首圈放电后石墨与插层的BiCl_(3)相互作用减弱,该过程有效促进了钠离子在石墨层内的存储。采用该方法可成功制备多种类型金属氯化物-石墨插层化合物,为开发高性能储能材料提供了可行思路。展开更多
氯化镍(NiCl_(2))作为一种高电位热电池正极材料,自身不佳的导电性限制了其在热电池中的应用。在本研究中,利用液相混合-低温煅烧工艺制备了亚铜离子掺杂的氯化镍(NiCl_(2)-Cu_(x))。其中NiCl_(2)-Cu5具备最佳的电化学性能,与NiCl_(2)相...氯化镍(NiCl_(2))作为一种高电位热电池正极材料,自身不佳的导电性限制了其在热电池中的应用。在本研究中,利用液相混合-低温煅烧工艺制备了亚铜离子掺杂的氯化镍(NiCl_(2)-Cu_(x))。其中NiCl_(2)-Cu5具备最佳的电化学性能,与NiCl_(2)相比,NiCl_(2)-Cu5展现出高电压、高比能量优势,尤其是在500 mA cm-2电流密度下,NiCl_(2)-Cu5展现出724 Wh kg-1的高比能量,相比于NiCl_(2)约提升了82%。脉冲测试证明,NiCl_(2)-Cu5正极材料具备更低的内阻,能够缓解放电过程中的欧姆极化,实现高比能量输出。这项工作为高性能热电池正极材料的开发提供了一种新的思路。展开更多
Nanostructured metal phosphides are very attractive materials in energy storage and conversion,but their applications are severely limited by complicated preparation steps,harsh conditions and large excess of highly t...Nanostructured metal phosphides are very attractive materials in energy storage and conversion,but their applications are severely limited by complicated preparation steps,harsh conditions and large excess of highly toxic phosphorus source.Here we develop a highly efficient one-step method to synthesize Sn_(4)P_(3)nanostructure based on simultaneous reduction of SnCl_(4)and PCl_(3)on mechanically activated Na surface and in situ phosphorization.The low-toxic PCl3 displays a very high phosphorizing efficiency(100%).Furthermore,this simple method is powerful to control phosphide size.Ultrafine Sn_(4)P_(3)nanocrystals(<5 nm)supported on carbon sheets(Sn_(4)P_(3)/C)are obtained,which is due to the unique bottom-up surface-limited reaction.As the anode material for sodium/lithium ion batteries(SIBs/LIBs),the Sn_(4)P_(3)/C shows profound sodiation/lithiation extents,good phase-conversion reversibility,excellent rate performance and long cycling stability,retaining high capacities of 420 mAh/g for SIBs and 760 mAh/g for LIBs even after 400 cycles at 1.0 A/g.Combining simple and efficient preparation,low-toxic and high-efficiency phosphorus source and good control of nanosize,this method is very promising for low-cost and scalable preparation of high-performance Sn_(4)P_(3)anode.展开更多
Chloride ion batteries(CIB) are considered to be one of the most promising energy storage devices. As cathode materials for CIBs, metal chlorides have many advantages, such as high theoretical energy density, abundant...Chloride ion batteries(CIB) are considered to be one of the most promising energy storage devices. As cathode materials for CIBs, metal chlorides have many advantages, such as high theoretical energy density, abundant elemental resources and ideal discharge voltage plateau. However, the dissolution and huge volume change of metal chlorides during cycling lead to considerable short lifespan, which limits their potential application for CIBs. Herein, the bismuth chloride nanocrystal is confined in mesocellular carbon foam matrix by a new vacuum impregnation approach. The mesocellular carbon foam with large interconnected pores(15.7 or 23.2 nm) may buffer the large volume variation of bismuth chloride during charge and discharge, giving rise to significantly enhanced electrochemical performance. The as-prepared bismuth chloride@mesocellular carbon foam cathode delivered an initial discharge capacity of 298 m Ah/g and a reversible capacity of 91 m Ah/g after 60 cycles. In contrast, the pure bismuth chloride cathode almost cannot discharge after 30 cycles. This is the first report that the metal chloride cathode can achieve a prolonged cycling in CIBs.展开更多
This study focused on the extraction of valuable metals from the cathode-active materials in spent lithiumion batteries using a high-concentration chloride solution.The effects of the concentrations of ammonium chlori...This study focused on the extraction of valuable metals from the cathode-active materials in spent lithiumion batteries using a high-concentration chloride solution.The effects of the concentrations of ammonium chloride(NH4 Cl),hydrochloric acid(HCl),and reductants such as hydrogen peroxide(H_(2)O_(2))and urea(CO(NH_(2))_(2))on metal extraction and chlorine production were studied experimentally.The leaching mechanism was analyzed,and a leaching model was established.It was found that the addition of solid NH4 Cl to an HCl solution significantly improved the metal extraction capability of the latter and reduced the formation of chlorine gas by 96.0%compared to that only using HCl.The activation energies for leaching Li,Ni,Co,and Mn were determined to be 30.4,38.5,30.6,and 38.2 kJ·mol^(-1),respectively.This study demonstrates an environmentally friendly method for recycling metal resources from cathode-active materials and furthers understanding of how NH4 Cl inhibits chlorine production when leaching with mixed solutions of HCl and NH4 Cl.展开更多
基金the support of the National Energy-Saving and Low-Carbon Materials Production and Application Demonstration Platform Program (TC220H06N)the National Natural Science Foundation of China (51832004,51972259,52127816)the Natural Science Foundation of Hubei Province (2022CFA087)。
文摘In the scope of developing new electrochemical concepts to build batteries with high energy density,chloride ion batteries(CIBs)have emerged as a candidate for the next generation of novel electrochemical energy storage technologies,which show the potential in matching or even surpassing the current lithium metal batteries in terms of energy density,dendrite-free safety,and elimination of the dependence on the strained lithium and cobalt resources.However,the development of CIBs is still at the initial stage with unsatisfactory performance and several challenges have hindered them from reaching commercialization.In this review,we examine the current advances of CIBs by considering the electrode material design to the electrolyte,thus outlining the new opportunities of aqueous CIBs especially combined with desalination,chloride redox battery,etc.With respect to the developing road of lithium ion and fluoride ion batteries,the possibility of using solid-state chloride ion conductors to replace liquid electrolytes is tentatively discussed.Going beyond,perspectives and clear suggestions are concluded by highlighting the major obstacles and by prescribing specific research topics to inspire more efforts for CIBs in large-scale energy storage applications.
基金the financial support from the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0450201)the National Key R&D Program of China(2018YFA0209600)+2 种基金USTC Research Funds of the Double FirstClass Initiative(YD2060002033)the Fundamental Research Funds for the Central Universities(WK2060000060)the National Synchrotron Radiation Laboratory(KY2060000199)。
文摘Chloride solid electrolytes possess multiple advantages for the construction of safe,energy-dense allsolid-state sodium batteries,but presently the chlorides with sufficiently high cost-competitiveness for commercialization almost all exhibit low Na-ion conductivities of around 10^(-5)S cm^(-1)or lower.Here,we report a chloride solid electrolyte,Na_(2.7)ZFCl_(5.3)O_(0.7),which reaches a Na-ion conductivity of 2.29×10^(-4)S cm^(-1)at 25℃without involving overly expensive raw materials such as rare-earth chlorides or Na_(2)S.In addition to the efficient ion transport,Na_(2.7)ZrCl_(5.3)O_(0.7)also shows an excellent deformability surpassing that of the widely studied Na_(3)PS_(4),Na_(3)SbS_(4),and Na_(2)ZrCl_(6)solid electrolytes.The combination of these advantages allows the all-solid-state cell based on Na_(2.7)ZrCl_(5.3)O_(0.7)and NaCrO_(2)to realize stable room-temperature cycling at a much higher specific current than those based on other non-viscoelastic chloride solid electrolytes in literature(120 mA g^(-1)vs.12-55 mA g^(-1));after 100 cycles at such a high rate,the Na_(2.7)ZFCl_(5.3)O_(0.7)-based cell can still deliver a discharge capacity of 80 mAh g^(-1)at25℃.
基金This work was financially supported by the National Key R&D Program of China(No.2016YFB0100301)the National Natural Science Foundation of China(Nos.21875022 and U1664255).
文摘The reductant is a critical factor in the hydrometallurgical recycling of valuable metals from spent lithium-ion batteries(LIBs).There is limited information regarding the use of SnCl_(2) as a reductant with organic acid(maleic acid)for recovering valuable metals from spent Li-CoO_(2) material.In this study,the leaching efficiencies of Li and Co with 1 mol·L^(−1) of maleic acid and 0.3 mol·L^(−1) of SnCl_(2) were found to be 98.67%and 97.5%,respectively,at 60°C and a reaction time of 40 min.We investigated the kinetics and thermodynamics of the leaching process in this study to better understand the mechanism of the leaching process.Based on a comparison with H_(2)O_(2) with respect to leaching efficiency,the optimal leaching parameters,and the activation energy,we determined that it is feasible to replace H_(2)O_(2) with SnCl_(2) as a leaching reductant in the leaching process.In addition,when SnCl_(2) is used in the acid-leaching process,Sn residue in the leachate may have a positive effect on the re-synthesis of nickel-rich cathode materials.Therefore,the results of this study provide a potential direction for the selection of reductants in the hydrometallurgical recovery of valuable metals from spent LIBs.
基金We acknowledge the financial support from the National Natural Science Foundation of China(NSFC)(21875055 and 21674031)the Natural Science Foundation of Guangdong Province of China(2019A1515110447)+3 种基金the Guangdong Basic and Applied Basic Research Foundation(2019B1515120008)the Key-Area Research and Development Program of Guangdong Province(2021B0101260001)and the Characteristic Innovation Research Project of College Teachers of Foshan(2019XCC03)Open access funding provided by Shanghai Jiao Tong University
文摘Aqueous zinc ion batteries have high potential applicability for energy storage due to their reliable safety,environmental friendliness,and low cost.However,the freezing of aqueous electrolytes limits the normal operation of batteries at low temperatures.Herein,a series of high-performance and low-cost chloride hydrogel electrolytes with high concentrations and low freezing points are developed.The electrochemical windows of the chloride hydrogel electrolytes are enlarged by>1 V under cryogenic conditions due to the obvious evolution of hydrogen bonds,which highly facilitates the operation of electrolytes at ultralow temperatures,as evidenced by the low-temperature Raman spectroscopy and linear scanning voltammetry.Based on the Hofmeister effect,the hydrogen-bond network of the cooperative chloride hydrogel electrolyte comprising 3 M ZnCl_(2)and 6 M LiCl can be strongly interrupted,thus exhibiting a sufficient ionic conductivity of 1.14 mS cm;and a low activation energy of 0.21 e V at-50℃.This superior electrolyte endows a polyaniline/Zn battery with a remarkable discharge specific capacity of 96.5 mAh g;at-50℃,while the capacity retention remains~100%after 2000 cycles.These results will broaden the basic understanding of chloride hydrogel electrolytes and provide new insights into the development of ultralow-temperature aqueous batteries.
基金Project(2007CB613607)supported by National Basic Research Program of China
文摘LiNi0.8Co0.1Mn0.1O2 was prepared by a chloride co-precipitation method and characterized by thermogravimetric analysis, X-ray diffractometry with Rietveld refinement,electron scanning microscopy and electrochemical measurements.Effects of lithium ion content and sintering temperature on physical and electrochemical performance of LiNi0.8Co0.1Mn0.1O2 were also investigated. The results show that the sample synthesized at 750℃with 105%lithium content has fine particle sizes around 200 nm and homogenous sizes distribution.The initial discharge capacity for the powder is 184 mA·h/g between 2.7 and 4.3 V at 0.1C and room temperature.
基金supported by the National Key Research and Development Program of China (2022YFB4101600)the Fundamental Research Funds for the Central Universities (DUT22ZD207, DUT22LAB612)the Shandong Provincial Natural Science Foundation (ZR2023QB095)。
文摘金属氯化物-石墨插层化合物具有导电性优异,石墨层间距大等特点,可用作钠离子电池负极材料。然而,在传统金属氯化物插层石墨过程中,不可避免地用到氯气,既增加了实验操作的风险,也对实验设备提出更高要求。基于上述原因,本文创新性地使用SO_(2)Cl_(2)作为氯源来促进BiCl_(3)插层石墨。该方法不仅有效提高了BiCl_(3)插层效率,也避免了直接使用氯气带来的安全性风险。采用该方法所合成的三氯化铋-石墨插层化合物(BiCl_(3)-GICs)的层间距为1.26 nm,BiCl_(3)插层含量高达42%。以其为负极材料,组装的钠离子电池具有高的比容量(213 mAh g^(-1)at 1 A g^(-1))和优异的倍率性能(170 mAh g^(-1)at 5 A g^(-1))。此外,原位拉曼光谱测试结果表明,首圈放电后石墨与插层的BiCl_(3)相互作用减弱,该过程有效促进了钠离子在石墨层内的存储。采用该方法可成功制备多种类型金属氯化物-石墨插层化合物,为开发高性能储能材料提供了可行思路。
文摘氯化镍(NiCl_(2))作为一种高电位热电池正极材料,自身不佳的导电性限制了其在热电池中的应用。在本研究中,利用液相混合-低温煅烧工艺制备了亚铜离子掺杂的氯化镍(NiCl_(2)-Cu_(x))。其中NiCl_(2)-Cu5具备最佳的电化学性能,与NiCl_(2)相比,NiCl_(2)-Cu5展现出高电压、高比能量优势,尤其是在500 mA cm-2电流密度下,NiCl_(2)-Cu5展现出724 Wh kg-1的高比能量,相比于NiCl_(2)约提升了82%。脉冲测试证明,NiCl_(2)-Cu5正极材料具备更低的内阻,能够缓解放电过程中的欧姆极化,实现高比能量输出。这项工作为高性能热电池正极材料的开发提供了一种新的思路。
基金support from the National Natural Science Foundation of China(Nos.51972075 and 51772059)the Natural Science Foundation of Heilongjiang Province(No.ZD2019E004)the Fundamental Research funds for the Central Universities.
文摘Nanostructured metal phosphides are very attractive materials in energy storage and conversion,but their applications are severely limited by complicated preparation steps,harsh conditions and large excess of highly toxic phosphorus source.Here we develop a highly efficient one-step method to synthesize Sn_(4)P_(3)nanostructure based on simultaneous reduction of SnCl_(4)and PCl_(3)on mechanically activated Na surface and in situ phosphorization.The low-toxic PCl3 displays a very high phosphorizing efficiency(100%).Furthermore,this simple method is powerful to control phosphide size.Ultrafine Sn_(4)P_(3)nanocrystals(<5 nm)supported on carbon sheets(Sn_(4)P_(3)/C)are obtained,which is due to the unique bottom-up surface-limited reaction.As the anode material for sodium/lithium ion batteries(SIBs/LIBs),the Sn_(4)P_(3)/C shows profound sodiation/lithiation extents,good phase-conversion reversibility,excellent rate performance and long cycling stability,retaining high capacities of 420 mAh/g for SIBs and 760 mAh/g for LIBs even after 400 cycles at 1.0 A/g.Combining simple and efficient preparation,low-toxic and high-efficiency phosphorus source and good control of nanosize,this method is very promising for low-cost and scalable preparation of high-performance Sn_(4)P_(3)anode.
基金supported by the National Natural Science Foundation of China (No. 51602150)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)the Opening Project of CAS Key Laboratory of Materials for Energy Conversion。
文摘Chloride ion batteries(CIB) are considered to be one of the most promising energy storage devices. As cathode materials for CIBs, metal chlorides have many advantages, such as high theoretical energy density, abundant elemental resources and ideal discharge voltage plateau. However, the dissolution and huge volume change of metal chlorides during cycling lead to considerable short lifespan, which limits their potential application for CIBs. Herein, the bismuth chloride nanocrystal is confined in mesocellular carbon foam matrix by a new vacuum impregnation approach. The mesocellular carbon foam with large interconnected pores(15.7 or 23.2 nm) may buffer the large volume variation of bismuth chloride during charge and discharge, giving rise to significantly enhanced electrochemical performance. The as-prepared bismuth chloride@mesocellular carbon foam cathode delivered an initial discharge capacity of 298 m Ah/g and a reversible capacity of 91 m Ah/g after 60 cycles. In contrast, the pure bismuth chloride cathode almost cannot discharge after 30 cycles. This is the first report that the metal chloride cathode can achieve a prolonged cycling in CIBs.
基金the National Key Research and Development Program(No.2018YFB0605702)the National Natural Science Foundation of China(Nos.51774260,21606241 and 51804289)+1 种基金the Key Research Program of Frontier Sciences of Chinese Academy of Sciences(No.QYZDJ-SSW-JSC021)CAS Interdisciplinary Innovation Team。
文摘This study focused on the extraction of valuable metals from the cathode-active materials in spent lithiumion batteries using a high-concentration chloride solution.The effects of the concentrations of ammonium chloride(NH4 Cl),hydrochloric acid(HCl),and reductants such as hydrogen peroxide(H_(2)O_(2))and urea(CO(NH_(2))_(2))on metal extraction and chlorine production were studied experimentally.The leaching mechanism was analyzed,and a leaching model was established.It was found that the addition of solid NH4 Cl to an HCl solution significantly improved the metal extraction capability of the latter and reduced the formation of chlorine gas by 96.0%compared to that only using HCl.The activation energies for leaching Li,Ni,Co,and Mn were determined to be 30.4,38.5,30.6,and 38.2 kJ·mol^(-1),respectively.This study demonstrates an environmentally friendly method for recycling metal resources from cathode-active materials and furthers understanding of how NH4 Cl inhibits chlorine production when leaching with mixed solutions of HCl and NH4 Cl.