摘要:
The invention provides a new route for the synthesis of carbon-coated powders having the olivine or NASICON structure, which form promising classes of active products for the manufacture of rechargeable lithium batteries. Carbon-coating of the powder particles is necessary to achieve good performances because of the rather poor electronic conductivity of said structures. For the preparation of coated LiFePO4, sources of Li, Fe and phosphate are dissolved in an aqueous solution together with a polycarboxylic acid and a polyhydric alcohol. Upon water evaporation, polyesterification occurs while a mixed precipitate is formed containing Li, Fe and phosphate. The resin-encapsulated mixture is then heat treated at 700° C. in a reducing atmosphere. This results in the production of a fine powder consisting of an olivine LiFePO4 phase, coated with conductive carbon. When this powder is used as active material in a lithium insertion-type electrode, fast charge and discharge rates are obtained at room temperature and an excellent capacity retention is observed.
摘要:
The invention provides a new route for the synthesis of carbon-coated powders having the olivine or NASICON structure, which form promising classes of active products for the manufacture of rechargeable lithium batteries. Carbon-coating of the powder particles is necessary to achieve good performances because of the rather poor electronic conductivity of said structures. For the preparation of coated LiFePO4, sources of Li, Fe and phosphate are dissolved in an aqueous solution together with a polycarboxylic acid and a polyhydric alcohol. Upon water evaporation, polyesterification occurs while a mixed precipitate is formed containing Li, Fe and phosphate. The resin-encapsulated mixture is then heat treated at 700° C. in a reducing atmosphere. This results in the production of a fine powder consisting of an olivine LiFePO4, phase, coated with conductive carbon. When this powder is used as active material in a lithium insertion-type electrode, fast charge and discharge rates are obtained at room temperature and an excellent capacity retention is observed.
摘要:
The invention provides a new route for the synthesis of carbon-coated powders having the olivine or NASICON structure, which form promising classes of active products for the manufacture of rechargeable lithium batteries. Carbon-coating of the powder particles is necessary to achieve good performances because of the rather poor electronic conductivity of said structures. For the preparation of coated LiFePO4, sources of Li, Fe and phosphate are dissolved in an aqueous solution together with a polycarboxylic acid and a polyhydric alcohol. Upon water evaporation, polyesterification occurs while a mixed precipitate is formed containing Li, Fe and phosphate. The resin-encapsulated mixture is then heat treated at 700° C. in a reducing atmosphere. This results in the production of a fine powder consisting of an olivine LiFePO4 phase, coated with conductive carbon. When this powder is used as active material in a lithium insertion-type electrode, fast charge and discharge rates are obtained at room temperature and an excellent capacity retention is observed.
摘要:
The invention provides a new route for the synthesis of carbon-coated powders having the olivine or NASICON structure, which form promising classes of active products for the manufacture of rechargeable lithium batteries. Carbon-coating of the powder particles is necessary to achieve good performances because of the rather poor electronic conductivity of said structures. For the preparation of coated LiFePO4, sources of Li, Fe and phosphate are dissolved in an aqueous solution together with a polycarboxylic acid and a polyhydric alcohol. Upon water evaporation, polyesterification occurs while a mixed precipitate is formed containing Li, Fe and phosphate. The resin-encapsulated mixture is then heat treated at 700° C. in a reducing atmosphere. This results in the production of a fine powder consisting of an olivine LiFePO4 phase, coated with conductive carbon. When this powder is used as active material in a lithium insertion-type electrode, fast charge and discharge rates are obtained at room temperature and an excellent capacity retention is observed.
摘要:
The invention provides a new route for the synthesis of carbon-coated powders having the olivine or NASICON structure, which form promising classes of active products for the manufacture of rechargeable lithium batteries. Carbon-coating of the powder particles is necessary to achieve good performances because of the rather poor electronic conductivity of said structures. For the preparation of coated LiFePO4, sources of Li, Fe and phosphate are dissolved in an aqueous solution together with a polycarboxylic acid and a polyhydric alcohol. Upon water evaporation, polyesterification occurs while a mixed precipitate is formed containing Li, Fe and phosphate. The resin-encapsulated mixture is then heat treated at 700° C. in a reducing atmosphere. This results in the production of a fine powder consisting of an olivine LiFePO4 phase, coated with conductive carbon. When this powder is used as active material in a lithium insertion-type electrode, fast charge and discharge rates are obtained at room temperature and an excellent capacity retention is observed.
摘要:
Methods of manufacture and use of phosphates of transition metals are described as positive electrodes for secondary lithium batteries, including a process for the production of LiMPO4 with controlled size and morphology, M being FexCoyNizMnw, where 0≦x≦1,0≦y≦1, 0≦w≦1, and x+y+z+w=1. According to an exemplary embodiment, a process is described for the manufacture of LiFePO4 including the steps of providing an equimolar aqueous solution of Li1+, Fe3+ and PO43−, evaporating water from the solution to produce a solid mixture, decomposing the solid mixture at a temperature of below 500° C. to form a pure homogeneous Li and Fe phosphate precursor, and annealing the precursor at a temperature of less than 800° C. in a reducing atmosphere to produce the LiFePO4 powder. The obtained powders can have a particle size of less than 1 μm, and can provide superior electrochemical performance when mixed for an appropriate time with an electrically conductive powder.
摘要翻译:过渡金属的磷酸盐的制造和使用方法被描述为二次锂电池的正电极,包括用于制备具有受控尺寸和形态的LiMPO 4的方法,M是Fe x x 其中0 <= x <= 1,0 <= y <= 1,0
摘要:
Methods of manufacture and use of phosphates of transition metals are described as positive electrodes for secondary lithium batteries, including a process for the production of LiMPO4 with controlled size and morphology, M being FexCoyNizMnw, where 0≦x≦1, 0≦y≦1, 0≦w≦1, and x+y+z+w=1. According to an exemplary embodiment, a process is described for the manufacture of LiFePO4 including the steps of providing an equimolar aqueous solution of Li1+, Fe3+ and PO43−, evaporating water from the solution to produce a solid mixture, decomposing the solid mixture at a temperature of below 500° C. to form a pure homogeneous Li and Fe phosphate precursor, and annealing the precursor at a temperature of less than 800° C. in a reducing atmosphere to produce the LiFePO4 powder. The obtained powders can have a particle size of less than 1 μm, and can provide superior electrochemical performance when mixed for an appropriate time with an electrically conductive powder.
摘要翻译:将过渡金属的磷酸盐的制造和使用方法描述为二次锂电池的正电极,包括用于制备具有受控尺寸和形态的LiMPO4的方法,M是FexCoyNizMnw,其中0≤x≤1,0< y <= 1,0 <= w <= 1,x + y + z + w = 1。 根据一个示例性实施方案,描述了制备LiFePO 4的方法,其包括以下步骤:提供Li1 +,Fe3 +和PO43-的等摩尔水溶液,从溶液中蒸发水以产生固体混合物,并在一定温度下分解固体混合物 在500℃以上以形成纯均匀的Li和Fe磷酸盐前体,并在还原气氛中在小于800℃的温度下退火前体以产生LiFePO 4粉末。 得到的粉末的粒径可以小于1μm,并且当与导电粉末混合适当的时间时,可提供优异的电化学性能。
摘要:
Methods of manufacture and use of phosphates of transition metals are described as positive electrodes for secondary lithium batteries, including a process for the production of LiMPO4 with controlled size and morphology, M being FexCoyNizMnw, where 0≦x≦1, 0≦y≦1, 0≦w≦1, and x+y+z+w=1. According to an exemplary embodiment, a process is described for the manufacture of LiFePO4 including the steps of providing an equimolar aqueous solution of Li1+, Fe3+ and PO43−, evaporating water from the solution to produce a solid mixture, decomposing the solid mixture at a temperature of below 500° C. to form a pure homogeneous Li and Fe phosphate precursor, and annealing the precursor at a temperature of less than 800° C. in a reducing atmosphere to produce the LiFePO4 powder. The obtained powders can have a particle size of less than 1 μm, and can provide superior electrochemical performance when mixed for an appropriate time with an electrically conductive powder.
摘要翻译:过渡金属磷酸盐的制造和使用方法被描述为二次锂电池的正电极,包括用于制备具有受控尺寸和形态的LiMPO4的方法,M是FexCoyNizMnw,其中0&nlE; x&nlE; 1,0&amp; nlE; y&nlE; 1 ,0&nlE; w&nlE; 1,x + y + z + w = 1。 根据一个示例性实施方案,描述了制备LiFePO 4的方法,其包括以下步骤:提供Li1 +,Fe3 +和PO43-的等摩尔水溶液,从溶液中蒸发水以产生固体混合物,并在一定温度下分解固体混合物 在500℃以上以形成纯均匀的Li和Fe磷酸盐前体,并在还原气氛中在小于800℃的温度下退火前体以产生LiFePO 4粉末。 得到的粉末可以具有小于1μm的粒度,并且当与导电粉末混合适当的时间时,可提供优异的电化学性能。
摘要:
The electrochemical performance of rechargeable lithium battery cells comprising crystalline or amorphous FeIII iron phosphate active positive electrode compounds is improved by compound hydration and intimate ball-milled incorporation of electrically conductive carbon.
摘要:
An electrode for a lithium ion battery includes a matrix based on at least one polysaccharide and also particles of at least one electrochemically active material which are embedded in the matrix, with the electrode being free of synthetic polymeric compounds. A battery contains the electrode and a polysaccharide is a binder for electrochemically active electrode materials for such an electrode.