A highly stable zinc anode protected by a corrosion inhibitor for seawater-based zinc-ion batteries

The island-based energy storage is of urgent need for the grid construction combined with renewable energy for offshore operation.The direct use of seawater as a substitute of deionized water shows its great promise for aqueous zinc-ion batteries in such a specific situation.However,the metal corrosion,dendrite growth,and hydrogen evolution stand out in the harsh seawater environment.To address these challenges,we proposed a corrosion inhibitor that was effective in the field of metal anti-corrosion,2-phosphonobutane-1,2,4-tricarboxylic acid(PBTCA),to inhibit anode corrosion caused by Cl-and active H_(2)O molecules by forming a stable solid electrolyte interphase(SEI)film in the seawater-based electrolyte.Besides,PBTCA can chelate with other cations present in seawater,such as Ca^(2+)and Mg^(2+),thereby preventing the aggregation and precipitation of sparingly soluble species.Under a current density of5 mA cm^(-2),the seawater-based zinc-ion battery exhibited an exceptional cycle life exceeding 2000 h and maintained a Coulombic efficiency of over 99.6%after 2000 cycles.Additionally,the performance of the Zn||ZVO full battery was significantly enhanced with the addition of PBTCA.This study provides a simple,low-cost,and efficient approach for making the seawater-based zinc-ion batteries useable.

Discharge behavior and electrochemical properties of Mg-Al-Sn alloy anode for seawater activated battery

Mg-Al-Sn alloy is one of the new developed anode materials for seawater activated batteries. The potentiodynamic polarization, galvanostatic discharge and electrochemical impedance spectroscopy of Mg-6%Al-1%Sn and Mg-6%Al-5%Sn(mass fraction) alloys in seawater were studied and compared with the commercial AZ31 and AP65 alloys. The results show that the Mg-6%Al-1%Sn alloy obtains the most negative discharge potential of average-1.611V with a electric current density of 100 mA/cm2. EIS studies reveal that the Mg-Al-Sn alloy/seawater interfacial electrochemical process is determined by an activation controlled reaction. The assembled prototype batteries with Mg-6%Al-1%Sn alloy as anodes and Ag Cl as cathodes exhibit a satisfactory integrated discharge properties.

Influence of simulating deep-sea environmental factors on cathodic performance of seawater battery

A metal-dissolved oxygen seawater battery(SWB)uses metal and dissolved oxygen as the reactants,and it is ideal for use as a long-time low-power distributed power supply in deep sea,due to its advantages of open structure in service without electrolyte.However,several simulating deep-sea environmental factors,such as flow rate,dissolved oxygen concentration,and temperature of seawater may af fect the oxygen reduction reaction(ORR)rate and the stability of electrochemically modified polyacrylonitrile-based carbon fiber brush(MPAN-CFB)cathode,which was studied by steady-state polarization and galvanostatic discharge methods.In addition,the scales formed on MPAN-CFB surface were characterized by SEM and XRD.Results show that the ORR rate increased quickly with the increase of the seawater flow rate up to 3 cm/s,and then gradually stabilized.Moreover,the ORR rate was largely af fected by dissolved oxygen concentration,and the concentration of>3 mg/L was favorable.Compared with surface layer temperature of 15℃,the low temperature of deep sea(4℃)has a negligible ef fect on ORR rate.When the working current is too high,it will lead to the formation of CaCO_3 scales(aragonite)of at the cathodic surface,resulting in the decrease of ORR rate,and consequently the damage to the long-time stability of MPAN-CFB.

Vacancy-modified bimetallic FeMoS_(x)/CoNiP_(x) heterostructure array for efficient seawater splitting and Zn-air battery

The development of highly efficient OER catalysts with superior durability for seawater electrolysis and Zn-air battery is important but challenging.Herein,the vacancy-modified heterostructured bimetallic Fe Mo S_(x)/Co Ni P_(x)OER electrocatalyst is exploited.Benefiting from the electron redistribution and reaction kinetics modulation resulting from vacancy introduction and heterojunction formation,it yields ultralow OER overpotentials of 196,276,303 m V in 1 M KOH and 197,318,348 m V in 1 M KOH+seawater at 10,500,1000 m A cm^(-2),respectively,surviving 600 h at 800 m A cm^(-2)without obvious decay.Further,FeMoS_(x)/CoNiP_(x)-based Zn-air battery not only affords the high peak power density of 214.5 m W cm^(-2)but also exhibits the small voltage gap of 0.698 V and long lifetime of 500 h at 10 m A cm^(-2),overmatching overwhelming majority of reported advanced catalysts.It is revealed experimentally that the OER process on rationally designed Fe Mo S_(x)/Co Ni P_(x)follows the adsorbate evolution mechanism and the ratedetermining step shifts from^(*)OOH formation in individual building blocks to^(*)OOH deprotonation process in FeMoS_(x)/CoNiP_(x),providing the directly proof of how the vacancy introduction and heterojunction formation affect the reaction kinetics.

Electrochemical properties of magnesium alloy anodes discharged in seawater

Magnesium alloys can be developed as anode materials for seawater activated batteries. The electrochemical properties of AZ31, AP65 and Mg-3%Ga-2%Hg alloy anodes discharged in seawater were studied. The potentiodynamic polarization shows that the Mg-3%Ga-2%Hg alloy provides more negative corrosion potentials than AZ31 or AP65 alloy. The galvanostatic discharge results show that the Mg-3%Ga-2%Hg alloy exhibits good electrochemical properties as anodes in seawater. And the EIS studies reveal that the magnesium alloy anode/seawater interfacial process is determined by an activation controlled reaction. The Mg3Hg and Mg21Ga5Hg3 phases in Mg-3%Ga-2%Hg alloy improve its electrochemical properties better than the Mg17（Al,Zn）12 phase in AZ31 and Mg（Pb） solid solution phase in AP65 alloys.

Spontaneous anchoring Cl intoα-Co(OH)_(2) as efficient and stable oxygen reduction electrocatalysts for seawater battery

Seawater battery is an advanced energy storage system that enables conversion of chemical energy to electricity by consuming metals,dissolved oxygen and seawater in anode,cathode and electrolyte,respectively.However,the oxygen reduction reaction(ORR)activity and stability of electrocatalysts can be easily deactivated due to the severe Cl~-permeation and corrosion in seawater electrolyte.Herein,we developed a structural buffer engineering strategy by spontaneously anchoring Cl~-intoα-Co(OH)_(2) as efficient and stable ORR electrocatalysts,in which the ultrathinα-Co(OH)_(2) nanosheets were synthesized using an ultrafast solution high-temperature shock(SHTS)strategy.The large lattice space(~0.8 nm)of layeredα-Co(OH)_(2) ensured the spontaneously penetration of Cl~-into the lattice structure and replaced part of OH~-to formα-Co(OH)_(2-x)Cl_x.The continuous leaching and compensating of saturated Cl inα-Co(OH)_(2-x)Cl_x could enhance the Cl~-corrosion resistance and modulate electronic structure of Co metallic sites,thus improving the ORR electrocatalytic activity and stability in seawater electrolyte.Theα-Co(OH)_(2-x)Cl_x seawater batteries display superior onset and half-wave potentials of 0.71 and 0.66 V,respectively,which are much better than the counterparts ofα-Co(OH)_(2) and ofβ-Co(OH)_(2) with no Cl~-penetrating and no buffer structure.Theα-Co(OH)_(2-x)Cl_x-based seawater batteries display stable open-circuit potential of 1.69 V and outstanding specific capacity of 1345 mAh·g^(-1).

三维碳纤维基复合材料及其在海水溶解氧电池中的应用性能

以三维碳纤维刷为基体通过一步水热还原法制备了石墨烯/铂复合电极(Pt-G/CFB),分析结果表明碳纤维丝束上均匀生长和包覆了大量Pt纳米微粒和石墨烯,Pt晶粒尺寸约3.1 nm;复合电极具有较大比表面积和丰富的介孔结构。Pt-G催化剂在氧还原反应(ORR)中表现出良好的催化性能和稳定性。将复合电极与Al合金阳极组成海水溶解氧电池进行放电测试,电池在低温、贫氧及小电流密度条件下放电性能良好,最大功率密度达到197 mW/L。

Al-Ga-In-Sn-Si合金阳极及海水溶解氧电池的电化学性能

通过Ga、In和Sn低熔点合金元素改性,成功制备了高负电位高活化Al-Ga-In-Sn-Si合金阳极,通过材料表征和电化学测试研究了Al-Ga-In-Sn-Si合金的腐蚀行为和电化学性能,并与碳纤维刷-石墨烯-铂(Pt-G@CFB)催化阴极搭建了海水溶解氧电池,考察了室内静态海水环境和实际海洋环境下电池不同恒电阻的长周期放电性能。结果表明,Al-Ga-In-Sn-Si合金的自腐蚀电位为-1.613 V(vs.Ag/AgCl),自腐蚀电流密度为1.431 mA/cm^(2)。随着负载电阻的增加,电池电压上升,在室内静态和实海动态海水中2000Ω的负载下海水溶解氧电池平均放电电压最高,分别为1.73和1.78 V,在1000Ω的负载下平均能量密度最大,分别为549.85和653.44 Wh/kg。

溶解氧海水电池海洋环境适应性研究进展

海洋能源供应是海洋水下探测网络的“心脏”。溶解氧海水电池是为大规模水下观测系统与海洋开发设备提供能源的重要选择。由于其开放结构设计,溶解氧海水电池的电化学性能和运行稳定性容易受到复杂海洋环境的影响。介绍了溶解氧海水电池的工作原理和应用领域,系统阐述了影响溶解氧海水电池输出性能及稳定性的几种主要海洋环境因素。系统总结了温度、溶解氧浓度、杂离子毒化、海水腐蚀及海洋生物污损等主要海洋环境影响因素对溶解氧海水电池的影响机制,并探讨了当前的控制策略。最后,展望了溶解氧海水电池电极材料设计及全电池器件改进的研究方向,为进一步推动溶解氧海水电池在实况海洋环境中的应用提供思路。

Electrochemical behavior of Mg-Al-Zn-Ga-In alloy as the anode for seawater-activated battery

The effect of indium alloying on the corrosion and discharge behaviors of Mg-Al-Zn-Ga alloys is investigated via materials characterization,immersion test and electrochemical methods.The results indicate that indium alloying can effectively modify the distribution of intermetallic phases in Mg matrix via promoting the segregation of Al in the form of Mg17Al12 in matrix.The addition of indium can effectively activate Mg-Al-Zn-Ga alloy evidenced by increased hydrogen evolution volume and weight loss,negative shift of corrosion and discharge potentials,increase of corrosion current density,decrease of polarization resistance and promoted Faradic efficiency.Nonetheless,excessive indium alloying(2.0 wt.%)would strikingly deteriorate the electrochemical performance of Mg-Al-Zn-Ga anode due to the exorbitant active effect.The Mg-6 wt.%Al-3 wt.%Zn-1 wt.%Ga-1 wt.%In in as-cast state with acceptable corrosion rate and desirable discharge performance is a low cost,non-toxic and well-performance magnesium alloy,which is a promising anode materials for seawater-activated batteries.

海水激活电池电解液流动特性仿真

动力电源是无人水下航行器(UUV)的关键部件,是制约UUV更新换代的瓶颈之一。选取现有海水激活电池作为研究对象,针对海水激活电池在主流场内海水流动阻力大、电化学反应不充分等问题,基于Ansys Fluent对不同流量下电解液流道内部流场的流动特性进行仿真计算,以期为海水激活电池电解液流道的结构优化提供参考。结果表明:随着进液口电解液流量增加,电极板流场内压力分布均匀性逐渐变差;进液口的4条支流道内部通道及出口处尾流的流速变快,速度不均匀度增加;电极板流场内漩涡变大且回流范围扩大,流速不均匀面积明显变大。

海水激活电池电解液流道特性分析及结构优化

作为无人水下航行器(UUV)的重要组成部分,动力电池一直是UUV负载设备及动力系统正常工作和性能提升的主要影响因素,动力电池的发展是未来UUV更新换代的关键。选取海水激活电池作为研究对象,针对海水激活电池在主流场内海水流动均匀性差、电化学反应不充分等问题,基于Ansys Fluent对不同流量下电解液流道内部流场的流动特性进行仿真计算,根据分析结果对流道结构进行优化。对比电解液流道结构优化前后流动特性发现,流道结构优化后的电解液流道入口及出口支流道内压力变化小,且电极板主流场压力梯度明显变缓;进液口各支流道速度差变小,电极板主流场低速区的流速增大,流速最大峰谷距降低53%;电极板流场内漩涡变小且回流范围缩小,流速不均匀面积明显减小。

构筑高效耐腐蚀的碳铠甲层包覆Co_(9)Se_(8)电催化剂用于海水基锌空气电池

得益于较高的理论能量密度、环境友好性和丰富的海水储量,海水基锌-空气电池(S-ZABs)被认为是一种极具应用前景的储能和能源转换装置,是解决能源短缺和环境污染问题的能源装置之一。然而对于S-ZABs而言,构筑在海水中具有高耐氯离子腐蚀性与高性能的阴极氧还原反应电催化剂仍然具有挑战性。因此,我们通过高温硒化策略,在氮掺杂介孔碳材料上设计了超薄碳铠甲层封装的Co_(9)Se_(8)纳米颗粒高效ORR电催化剂(命名为NMC-Co_(9)Se_(8))。外部的超薄碳铠甲层不仅可以改善催化过程中的电子转移过程,抑制纳米颗粒的团聚,而且可以作为盔甲保护内部活性位点免受Cl^(-)吸附和腐蚀。得益于这种独特的结构,NMC-Co_(9)Se_(8)在0.1 mol·L^(-1)KOH海水电解质中表现出优异的ORR性能,其起始电位为0.904V,半波电位为0.860 V。更重要的是,基于NMC-Co_(9)Se_(8)催化剂的S-ZABs可提供172.4 m W·cm^(-2)的功率密度和超过150h的优异长期放电稳定性,均高于基于Pt/C的S-ZABs性能。这项工作为开发用于海水基锌-空气电池和其他能源转换技术具有耐氯离子腐蚀且高效的ORR催化剂提供了新思路。

海水电池AgO电极性能改善研究

采用化学合成法制备AgO粉末,通过控制适当的反应物浓度和反应温度,制备得到96%纯度以上的AgO粉末。使用不同粘合剂和不同结构导电骨架制备电极,进一步组装成海水电池测试不同制备方法下电池的电性能,结果显示当添加1%含量的PVDF作为粘合剂,使用多层蜂窝状银网作为导电骨架时,AgO电极的电性能提升较明显。

Microstructures and electrochemical corrosion properties of Mg-Al-Pb and Mg-Al-Pb-Ce anode materials

Mg-Al-Pb alloy is a good candidate for the anode material of magnesium seawater battery. For improving the low current utilization efficiency of Mg-Al-Pb alloy, the influence of Ce on the microstructures and electrochemical corrosion properties in a 3.5% NaCl solution was investigated using scanning electron microscope and electrochemical measurements. The results indicate that Ce refines the grain structure of Mg-Al-Pb alloy. The formation of strip Al11Ce3 second phase promotes the uniform distribution of Mg17Al12 phase in Mg-Al-Pb-Ce alloy. The addition of cerium accelerates the discharge activity of Mg-Al-Pb alloy. Due to a large number of cathodic Al11Ce3 and MglyAla2 phases, Ce promotes the micro-galvanic corrosion and leads to larger corrosion current density and hydrogen evolution rate in Mg-Al-Pb-Ce alloy than those in Mg-Al-Pb alloy. However, Mg-Al-Pb alloy expresses smaller utilization efficiency than Mg-Al-Pb-Ce alloy because of grain detachment.

Influence of Al-Mn master alloys on microstructures and electrochemical properties of Mg-Al-Pb-Mn alloys

Mg-Al-Pb alloy is one of the newly developed materials for the seawater activated batteries. As-cast Mg-6Al-5Pb and Mg-6Al-5Pb-0.5Mn alloys with different additions of Al-15%Mn （mass fraction）, Al-30%Mn and Al-50%Mn master alloys were prepared by melting and casting. Their microstructures were observed by optical microscopy and scanning electron microscopy. The electrochemical properties, hydrogen evolution and mass loss of Mg-6Al-5Pb-0.5Mn alloys were studied. The results show that Mg-6Al-5Pb-0.5Mn alloy added with Al-50%Mn master alloy provides more negative corrosion average potential （-1.66 V）, smaller corrosion current density （7 μm/cm2） and lower free corrosion rate （0.51 mg·cm-2·h-1） than other alloys. This is probably attributed to the presence of Al11Mn4 phase, which facilitates the self-peeling of corrosion products and enlarges the electrochemical reaction area as well as enhances the electrochemical activity.

从原理及特点出发探讨海水电池的应用前景

能源供给是海洋能源与资源开发需重点突破的核心共性关键技术。针对目前海洋供电存在的问题和局限性,探讨了一种利用海水做组件、具有灵活的分布式电源特征的化学海洋能供电装备—海水电池。根据海水在电池系统中所起的不同作用将其分类,分析了各类海水电池的原理和特点,并结合近年来的最新研究如导电聚苯胺复合二氧化锰正极、超级电容器、高能量和高功率双功能自动切换及可充放电的概念海水电池,分析了其应用和发展前景。尤其对海水激活电池和海水溶解氧电池,提出了未来的发展思路。

海水电池用镁阳极的研究与应用

镁阳极材料具有电负性好,比能量高以及密度小等优异性能,在海水电池领域具有广阔的应用前景。综述了近年来国内外镁阳极海水电池的研究及应用,讨论镁阳极材料的活化机制和腐蚀行为,探讨合金元素和第二相对镁阳极电化学活性和耐腐蚀性能的影响,指出今后海水电池用镁阳极材料的发展应在充分研究合金元素活化机理和第二相影响的基础上,研制出自腐蚀速率更小、阳极利用率更高以及比能量更大的新型镁合金阳极材料。

镁阳极在海水激活电池中的应用

金属镁拥有较负的标准电极电位(-2.37 V(相对于标准氢电极))、较大的理论比容量(2.2 A·h·g^(-1))和较小的相对密度(1.74 g/cm^3),是一种极具应用前景的海水激活电池阳极材料。概述近几年国内外镁阳极在不同类型海水激活电池中的应用,针对放电过程中金属镁存在的腐蚀产物剥落困难、析氢副反应严重和金属颗粒脱落等问题,探讨合金化、热处理和塑性变形等改性措施对镁阳极电化学性能的影响,为高性能镁阳极材料的制备提供理论依据,同时指出未来镁阳极材料的研究方向。

海水超级电容溶解氧电池

以氧化处理的碳纤维刷(Carbon fibre brush,CFB)作阴极材料,提出海水超级电容溶解氧电池(Seawaterbattery with electrochemical capacitance,SWB-EC)概念,并制造了3台实海测试样机.分别由循环伏安和稳态恒流放电方法研究了氧化处理前后的CFB和镁合金牺牲阳极的放电性能.结果表明:氧化处理的CFB具有准电容特性,在动态海水中其氧阴极还原反应(Oxygen reduction reaction,ORR)活性比未处理的CFB有大幅度提高;镁合金牺牲阳极的开路电位为-1.74 V,工作电位高,溶解较均匀.用以上阴、阳极材料制成3台样机作连续实海放电测试,经运行2个月,相关实验数据分析表明,与商品化海水电池SWB1200初步相比,该海水超级电容溶解氧电池具有更高的体积比功率密度.