WO2016141861A1 - 电池、电池组和不间断电源 - Google Patents

电池、电池组和不间断电源 Download PDF

Info

Publication number
WO2016141861A1
WO2016141861A1 PCT/CN2016/075706 CN2016075706W WO2016141861A1 WO 2016141861 A1 WO2016141861 A1 WO 2016141861A1 CN 2016075706 W CN2016075706 W CN 2016075706W WO 2016141861 A1 WO2016141861 A1 WO 2016141861A1
Authority
WO
WIPO (PCT)
Prior art keywords
lead
battery
positive electrode
active material
negative electrode
Prior art date
Application number
PCT/CN2016/075706
Other languages
English (en)
French (fr)
Inventor
陈璞
端南朗
罗小松
Original Assignee
苏州宝时得电动工具有限公司
陈璞
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 苏州宝时得电动工具有限公司, 陈璞 filed Critical 苏州宝时得电动工具有限公司
Priority to US15/556,277 priority Critical patent/US10522869B2/en
Priority to EP16761088.0A priority patent/EP3267518B1/en
Publication of WO2016141861A1 publication Critical patent/WO2016141861A1/zh
Priority to US16/680,286 priority patent/US11211635B2/en

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/05Accumulators with non-aqueous electrolyte
    • H01M10/052Li-accumulators
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/04Construction or manufacture in general
    • H01M10/045Cells or batteries with folded plate-like electrodes
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/20Semi-lead accumulators, i.e. accumulators in which only one electrode contains lead
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/36Accumulators not provided for in groups H01M10/05-H01M10/34
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/36Selection of substances as active materials, active masses, active liquids
    • H01M4/362Composites
    • H01M4/366Composites as layered products
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/36Selection of substances as active materials, active masses, active liquids
    • H01M4/38Selection of substances as active materials, active masses, active liquids of elements or alloys
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/36Selection of substances as active materials, active masses, active liquids
    • H01M4/38Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H01M4/42Alloys based on zinc
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/36Selection of substances as active materials, active masses, active liquids
    • H01M4/48Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/50Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
    • H01M4/505Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0013Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries acting upon several batteries simultaneously or sequentially
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00Electrolytes
    • H01M2300/0002Aqueous electrolytes
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the invention belongs to the field of batteries, and in particular relates to a battery.
  • the invention also relates to a battery pack comprising a plurality of batteries.
  • the invention also relates to an uninterruptible power supply.
  • the lead-acid battery has been in existence for more than 100 years and has mature battery technology, occupying an absolute market share in the energy storage fields such as automobile starter batteries, electric bicycles and UPS.
  • the lead-acid battery has a low cycle life and a relatively low energy density, it has the advantages of very low price and very high cost performance. Therefore, in recent years, nickel-metal hydride batteries, lithium-ion batteries, sodium-sulfur batteries, and liquid flow batteries have failed to replace lead-acid batteries in the field of energy storage.
  • the positive electrode of the secondary battery is capable of undergoing a reversible elution-embedding reaction based on the first metal ion
  • the negative electrode is capable of undergoing a reversible reduction deposition-oxidation dissolution reaction based on the second metal ion, the electrolyte containing the first metal participating in the positive electrode extraction-embedding reaction Ions and a second metal ion that participates in the negative electrode deposition-dissolution reaction.
  • the electrolyte of this type of battery is an aqueous solution, and there is no safety hazard similar to the organic electrolyte in a lithium ion battery, and it is environmentally friendly, low in cost, and high in energy density. Therefore, this type of battery is very promising as a next-generation energy storage battery to replace lead-acid batteries, which has great application value.
  • the second metal ion of the battery of this type may be zinc ion.
  • the negative electrode active material is metal zinc.
  • such a negative electrode active material has problems such as dendrite when charged and discharged in an aqueous solution, thereby causing cycle performance and charge and discharge capacity of the battery. affected. Therefore, the prior art needs further improvement.
  • the technical problem to be solved by the present invention is to provide a battery capable of improving the dendrite problem of the negative electrode, effectively improving the cycle life of the battery, and improving the electrochemical performance of the battery.
  • a battery comprising a positive electrode, a negative electrode and an electrolyte, the positive electrode comprising a positive electrode active material and a positive electrode current collector;
  • the electrolyte includes a first metal ion capable of reversibly deintercalating-embedded in a positive electrode during charging and discharging, and a second metal ion capable of being reducedly deposited as a second metal at the negative electrode and The second metal can be reversibly oxidized and dissolved into a second metal ion;
  • the negative electrode includes a negative electrode active material and a negative electrode current collector;
  • the negative electrode active material has a lead-containing substance on the surface or/and the electrolyte, and the lead-containing substance
  • the mass ratio of lead to the battery is not more than 1000 ppm.
  • the lead-containing substance in the surface of the negative active material includes lead metal.
  • the lead-containing substance in the electrolyte includes lead ions.
  • the mass ratio of lead to electrolyte in the lead-containing substance in the electrolyte is not less than 10 ppm.
  • the lead-containing substance includes at least one of metal lead, lead sulfate, and lead oxide.
  • the battery includes an additive cerium compound added to the negative electrode and/or the electrolyte.
  • the cerium compound is selected from the group consisting of antimony trioxide and/or cerium nitrate.
  • the bismuth compound comprises from 0.01 to 5% by weight based on the total weight of the electrolyte.
  • the ruthenium compound is from 0.1 to 10% by weight based on the total weight of the negative electrode.
  • the negative active material includes zinc.
  • the negative current collector comprises a brass foil.
  • the cathode current collector comprises a nylon mesh carrier and a graphite foil coated on the nylon mesh carrier.
  • the first metal ion comprises a lithium ion, a sodium ion or a magnesium ion.
  • the second metal ion comprises zinc ions.
  • the electrolyte is an aqueous electrolyte.
  • the positive active material comprises a lithium manganate modified material
  • the lithium manganate modified material conforms to the general formula Li 1+x Mn y M z O k , wherein M is selected from Pb, and ⁇ 1 ⁇ x ⁇ 0.5, 1 ⁇ y ⁇ 2.5, 0 ⁇ z ⁇ 0.1, 3 ⁇ k ⁇ 6.
  • the surface of the lithium manganate modified material is further coated with metal lead and/or lead oxide.
  • the surface of the positive active material has a coating layer, and the coating layer is metal lead and/or lead oxide.
  • the mass percentage of lead in the metal lead and/or lead oxide to the positive electrode active material ranges from 0.001% to 10%.
  • the present invention also provides a battery pack comprising a plurality of batteries as described above.
  • the present invention also provides an uninterruptible power supply comprising the battery as described above.
  • the beneficial effects of the present invention are: by adding a lead-containing substance on the surface of the negative electrode active material or/and the electrolyte, the dendrite problem of the negative electrode active material is alleviated, thereby increasing the cycle life of the battery and improving the battery power. Chemical properties and safety performance.
  • the technical problem to be solved by the present invention is to provide a lithium manganate modified material which has good chemical stability and high capacity, can be well matched with an aqueous electrolyte, and suppresses the reaction rate of side reactions, thereby improving the material. Electrochemical performance.
  • the technical solution adopted by the present invention is as follows: a lithium manganate modified material, the lithium manganate modified material conforms to the general formula Li 1+x Mn y M z O k , wherein M is selected from Pb, -1 ⁇ x ⁇ 0.5, 1 ⁇ y ⁇ 2.5, 0 ⁇ z ⁇ 0.1, and 3 ⁇ k ⁇ 6.
  • the lithium manganate modified material has a spinel structure.
  • the lithium manganate modified material has a median diameter ranging from 5 to 20 ⁇ m, and the lithium manganate modified material has a specific surface area ranging from 0.1 to 1.0 m 2 /g.
  • the surface of the lithium manganate modified material is further coated with metal lead and/or lead oxide.
  • the mass percentage of the lead in the metal lead and/or lead oxide and the lithium manganate modified material ranges from 0.001% to 10%.
  • the mass percentage of the lead in the metal lead and/or lead oxide and the lithium manganate modified material ranges from 0.1% to 5%.
  • the invention also provides a battery capable of effectively suppressing the positive side reaction rate, thereby further improving the self-discharge problem of the battery.
  • the technical solution provided by the present invention is: a battery including a positive electrode, a negative electrode, and an electrolyte, the positive electrode including a positive electrode active material and a positive electrode current collector, the electrolyte solution being an aqueous solution, and the positive electrode active material
  • a lithium manganate modified material as described above is included.
  • the electrolyte includes a first metal ion and a second metal ion, and the first metal ion can be reversibly extracted-embedded in the positive electrode during charging and discharging, and the second metal ion can be embedded in the negative electrode
  • the reduced deposition is a second metal and the second metal is reversibly oxidatively soluble into a second metal ion, the first metal ion being a lithium ion.
  • the second metal ion is a zinc ion.
  • the negative electrode includes a negative electrode active material and a negative electrode current collector
  • the lead active material has a lead-containing substance on a surface or/and an electrolyte
  • a mass ratio of lead in the lead-containing substance to the battery is not more than 1000ppm.
  • the electrolyte has a pH in the range of 2-8.
  • the present invention also provides a battery pack comprising a plurality of batteries, as described above.
  • the invention also provides a preparation method of the lithium manganate modified material as described above, characterized in that it comprises the following steps:
  • the lithium source, the manganese source and the lead source are mixed in a certain ratio, and the mixed product is subjected to heat treatment, the heat treatment temperature is 700-850 ° C, and the heat treatment time is 15-30 hours.
  • the beneficial effects of the invention are: by modifying the lead doped with lithium manganate, the stability of the modified material in the aqueous electrolyte is good, thereby inhibiting the interface between the material and the electrolyte.
  • the side reaction occurs to make the lithium manganate modified material have excellent capacity and cycle performance.
  • the self-discharge reduction, battery floatation performance, and cycle performance of the battery modified with such lithium manganate were significantly improved.
  • the technical problem to be solved by the present invention is to provide a composite positive electrode material which has good chemical stability and high capacity, can be well matched with an aqueous electrolyte, and suppresses the reaction rate of side reactions, thereby improving the electrochemical performance of the material. .
  • a composite positive electrode material comprising a positive electrode active material and a coating layer, the positive electrode active material comprising a lithium ion deintercalation compound, the coating
  • the layer is at least one of metal lead, lead monoxide or lead tetraoxide.
  • the lithium ion intercalation compound comprises at least one of lithium cobaltate, lithium nickelate and lithium manganate.
  • the composite positive electrode material has a median diameter ranging from 5 to 20 ⁇ m, and the composite positive electrode material has a specific surface area ranging from 0.1 to 1.0 m 2 /g.
  • the mass percentage of the lead in the metal lead, lead monoxide or lead tetraoxide and the positive electrode active material ranges from 0.001% to 10%.
  • the mass percentage of lead in the metal lead, lead monoxide or lead tetraoxide and the positive electrode active material ranges from 0.1% to 5%.
  • the invention also provides a battery capable of effectively suppressing the positive side reaction rate, thereby further improving the self-discharge problem of the battery.
  • the technical solution provided by the present invention is: a battery comprising a positive electrode, a negative electrode and an electrolyte, the positive electrode comprising a composite positive electrode material and a positive electrode current collector, the electrolyte solution being an aqueous solution, the composite positive electrode material
  • the positive electrode active material and the coating layer are included, and the positive electrode active material includes a lithium ion delta compound, and the coating layer is metal lead and/or lead oxide.
  • the electrolyte includes a first metal ion and a second metal ion, and the first metal ion can be reversibly extracted-embedded in the positive electrode during charging and discharging, and the second metal ion can be embedded in the negative electrode
  • the reduced deposition is a second metal and the second metal is reversibly oxidatively soluble into a second metal ion, the first metal ion being a lithium ion.
  • the second metal ion is a zinc ion.
  • the negative electrode includes a negative electrode active material and a negative electrode current collector
  • the lead active material has a lead-containing substance on a surface or/and an electrolyte
  • a mass ratio of lead in the lead-containing substance to the battery is not more than 1000ppm.
  • the mass percentage of lead in the metal lead and/or lead oxide to the positive electrode active material ranges from 0.001% to 10%.
  • the electrolyte has a pH in the range of 2-8.
  • the present invention also provides a battery pack comprising a plurality of batteries, as described above.
  • the beneficial effects of the present invention are: by coating a lithium ion deintercalation compound, the obtained composite positive electrode material has good stability in an aqueous electrolyte solution, thereby suppressing side reactions at the interface between the material and the electrolyte. Occurs to make the composite positive electrode material have excellent capacity and cycle performance. The self-discharge reduction, battery floatation performance, and cycle performance of the battery using the composite positive electrode material were significantly improved.
  • Example 1 is a graph showing discharge capacity, internal resistance of a battery, and cycle number of a battery in Example 1-1 and Comparative Example 1-1;
  • FIG. 2 is a graph showing absolute current density versus time of a working electrode of a three-electrode system battery in Examples 1-5 and Comparative Examples 1-3;
  • 3 is a working electrode of the three-electrode system battery of Example 1-5 after one hour of operation Scanning electron microscopy (SEM) image;
  • SEM scanning electron microscope
  • SEM scanning electron microscope
  • Figure 6 is a scanning electron microscope (SEM) image of the working electrode after one hour of operation of the three-electrode system battery in Comparative Examples 1-3.
  • the invention discloses a lithium manganate modified material, and the lithium manganate modified material conforms to the general formula Li 1+x Mn y M z O k , wherein M is selected from Pb, -1 ⁇ x ⁇ 0.5, 1 ⁇ y ⁇ 2.5, 0 ⁇ z ⁇ 0.1, 3 ⁇ k ⁇ 6.
  • the lead-doped lithium manganate modified material still maintains a spinel structure before doping, so that the lithium manganate modified material has good structural stability.
  • the lead-doped lithium manganate modified material is further coated with metal lead and/or lead oxide.
  • lead oxide includes at least one of lead monoxide, lead dioxide, and lead tetraoxide.
  • the lithium manganate modified material is coated with metal lead and/or lead oxide so that the coating layer can freely pass lithium ions while isolating the lithium manganate modified material and the aqueous electrolyte, thereby ensuring normal charging and discharging of the battery.
  • the side reaction at the interface between the positive electrode and the water-based electrolyte is avoided, and the self-discharge of the positive electrode is reduced.
  • the mass percentage of lead and lithium manganate modified material in the metal lead and/or lead oxide ranges from 0.001% to 10%. More preferably, the mass percentage of lead and lithium manganate modified material in the metal lead and/or lead oxide ranges from 0.1% to 5%. In this way, it is ensured that the lithium manganate modified material is well protected without affecting the energy density of the positive electrode.
  • the lithium manganate modified material has a median diameter D50 of 5 to 20 ⁇ m.
  • the present invention has a lithium manganate modified material having a median diameter of 5 to 20 ⁇ m to avoid the above problems.
  • the median particle diameter D50 may be 5-10 ⁇ m, 5-15 ⁇ m, 8 ⁇ m, 12 ⁇ m, 16 ⁇ m, 18 ⁇ m, and the like.
  • the lithium manganate modified material has a specific surface area of from 0.1 to 1.0 m 2 /g.
  • the specific surface area of the lithium manganate modified material ranges from 0.1 to 1.0 m 2 /g.
  • a method for preparing a lithium manganate modified material comprises the following steps:
  • the lithium source, the manganese source and the lead source are mixed in a certain ratio, and the mixed product is subjected to heat treatment, the heat treatment temperature is 700-850 ° C, and the heat treatment time is 15-30 hours.
  • a lithium source, a manganese source, and an M source are weighed according to a stoichiometric ratio of the general formula Li 1+x Mn y M z O k .
  • M is selected from Pb, -1 ⁇ x ⁇ 0.5, 1 ⁇ y ⁇ 2.5, 0 ⁇ z ⁇ 0.1, and 3 ⁇ k ⁇ 6.
  • the weighed lithium source, manganese source and lead source are mixed, and the mixture includes wet mixing and dry mixing.
  • the weighed lithium source, manganese source, and lead source are mixed in an alcohol, and mixed uniformly after mixing.
  • the uniformly stirred product is subjected to heat treatment, specifically, heat treatment is carried out in an oxygen-containing atmosphere under heat treatment at a heating rate of 1 to 10 ° C/min to 700 to 850 ° C, and heat treatment for 15 to 30 hours. Finally, the temperature is naturally lowered to room temperature to obtain a lead-doped lithium manganate modified material.
  • the lithium source includes, but is not limited to, lithium carbonate
  • the manganese source includes, but is not limited to, trimanganese tetraoxide
  • the lead source includes, but is not limited to, lead sulfate and lead oxide.
  • the lithium manganate modified material provided by the invention can improve the stability of the modified material in the aqueous electrolyte by modifying the lead doped with lithium manganate, thereby suppressing the side reaction at the interface between the material and the electrolyte.
  • the lithium manganate modified material has excellent capacity and cycle performance. Self-discharge reduction, battery floatation performance and circulation of a battery modified with such lithium manganate Performance has been significantly improved.
  • the invention discloses a composite positive electrode material, the composite positive electrode material comprises a positive electrode active material and a coating layer, and the positive electrode active material comprises a lithium ion deintercalation compound, and the coating layer is at least at least one of metal lead, lead monoxide or lead tetraoxide.
  • the composite positive electrode material comprises a positive electrode active material and a coating layer
  • the positive electrode active material comprises a lithium ion deintercalation compound
  • the coating layer is at least at least one of metal lead, lead monoxide or lead tetraoxide.
  • the surface of the positive electrode active material lithium ion delta compound is coated with at least one of lead, lead monoxide or lead trioxide.
  • the lithium ion deintercalation compound is coated with at least one of lead, lead monoxide or lead tetraoxide, so that the cladding layer can freely pass lithium ions while reducing the positive active material and the aqueous electrolyte, thereby ensuring
  • the battery is normally charged and discharged while avoiding the occurrence of side reactions at the interface between the positive electrode active material and the aqueous electrolyte, thereby reducing the self-discharge of the positive electrode.
  • the lithium ion delta compound includes at least one of lithium cobaltate, lithium nickelate, and lithium manganate.
  • the mass percentage of lead in the metal lead, lead monoxide or lead trioxide and the positive electrode active material ranges from 0.001% to 10%.
  • the coating layer is only a single component, such as metal lead, lead monoxide or lead tetraoxide, lead in lead metal or lead trioxide or lead in tetraoxide tetraoxide and positive active material
  • the mass percentage ranges from 0.001 to 10%.
  • the coating layer is a mixed component such as metal lead and lead monoxide
  • the total percentage of lead in the metal lead and lead monoxide to the positive electrode active material ranges from 0.001 to 10%.
  • the mass percentage of lead in the metal lead, lead monoxide or lead tetraoxide to the positive electrode active material ranges from 0.1% to 5%. In this way, it is ensured that the lithium manganate modified material is well protected without affecting the energy density of the positive electrode.
  • the composite positive electrode material has a median particle diameter D50 of 5 to 20 ⁇ m.
  • the present invention has a composite positive electrode material having a median diameter of 5-20 ⁇ m to avoid the above problems.
  • the median particle diameter D50 may be 5-10 ⁇ m, 5-15 ⁇ m, 12 ⁇ m, 14 ⁇ m, 16 ⁇ m, 18 ⁇ m, and the like.
  • the composite positive electrode material has a specific surface area of from 0.1 to 1.0 m 2 /g.
  • the composite positive electrode material of the present invention has a specific surface area ranging from 0.1 to 1.0 m 2 /g.
  • a method for preparing a composite positive electrode material comprises the following steps:
  • the positive electrode active material lithium ion deintercalation compound and the lead source were weighed according to a predetermined weight ratio.
  • the weighed lithium ion deintercalation compound and the lead source are mixed and stirred uniformly, so that the lead material of the coating material is uniformly coated on the lithium ion deintercalation compound.
  • Mixing includes dry blending and wet blending.
  • Solvents used in wet mixing include, but are not limited to, alcohol.
  • the mixed product is sintered.
  • the mixed product can be dried before sintering.
  • the sintering conditions are such that the temperature is raised to 400-650 ° C at a temperature increase rate of 1 to 10 ° C / min, and the temperature is maintained for 15 to 30 hours. Finally, the temperature is naturally lowered to room temperature to obtain a composite positive electrode material.
  • lead sources include, but are not limited to, lead acetate, lead monoxide, and lead tetraoxide.
  • the composite positive electrode material provided by the invention coats the lithium ion deintercalation compound, so that the coated material has good stability in the aqueous electrolyte, thereby inhibiting the side reaction at the interface between the material and the electrolyte, so that the lithium ion
  • the deintercalation compound has excellent capacity and cycle properties. The self-discharge reduction, battery floatation performance, and cycle performance of the battery using the composite positive electrode material were significantly improved.
  • the invention discloses a battery comprising a positive electrode, a negative electrode and an electrolyte, the positive electrode comprising a positive electrode active material and a positive electrode current collector; the electrolyte solution comprises a first metal ion and a second metal ion, and the first metal ion can be in the process of charging and discharging
  • the positive electrode is reversibly deintercalated-embedded, the second metal ion can be reducedly deposited as a second metal in the negative electrode and the second metal can be reversibly oxidized and dissolved into a second metal ion;
  • the negative electrode includes a negative electrode active material and a negative electrode current collector; and the negative electrode active material surface or/and
  • the electrolyte contains lead-containing substances, and the mass ratio of lead in the lead-containing substance to the battery is not more than 1000 ppm.
  • the charging and discharging principle of the battery of the present invention is: when charging, the positive electrode active material desorbs the first metal ion, and at the same time, the positive electrode active material is oxidized and emits electrons; and the electrons pass through the external electricity.
  • the road reaches the battery negative active material, and the second metal ion in the electrolyte is reduced on the negative active material and deposited on the negative active material.
  • the second metal of the negative active material is oxidized, and the lost electrons are converted into the second metal ions into the electrolyte; the electrons reach the positive electrode through the external circuit, the positive active material accepts the electrons to be reduced, and the first metal ions are embedded in the positive active material. in.
  • the positive electrode of the battery includes a positive electrode active material, and the positive electrode active material participates in the positive electrode reaction, and is capable of reversibly extracting-embedding the first metal ion.
  • the positive electrode active material may be a compound capable of reversible elution-intercalation lithium ion-doped spinel structure conforming to the general formula Li 1+x Mn y M z O k , wherein -1 ⁇ x ⁇ 0.5, 1 ⁇ y ⁇ 2.5,0 ⁇ z ⁇ 0.5, 3 ⁇ k ⁇ 6, M is at least one selected from the group consisting of Na, Li, Co, Mg, Ti, Cr, V, Zn, Zr, Si, and Al.
  • the positive electrode active material contains LiMn 2 O 4 .
  • the positive electrode active material may be a compound capable of reversibly deintercalating-intercalating lithium ion in a layered structure conforming to the general formula Li 1+x M y M′ z M′′ c O 2+n , wherein ⁇ 1 ⁇ x ⁇ 0.5, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 1, 0 ⁇ c ⁇ 1, -0.2 ⁇ n ⁇ 0.2, M, M', M" are respectively selected from Ni, Mn, Co, Mg, Ti, Cr, V, Zn, Zr At least one of Si, Si or Al.
  • the positive electrode active material contains LiCoO 2 .
  • the positive electrode active material may also be a compound having a olivine structure capable of reversibly extracting-intercalating lithium ions according to the general formula Li x M 1-y M' y (XO 4 ) n , wherein 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 0.6, 1 ⁇ n ⁇ 1.5, M is selected from Fe, Mn, V or Co, and M' is at least one selected from the group consisting of Mg, Ti, Cr, V or Al, and X is at least one selected from the group consisting of S, P or Si.
  • the positive electrode active material contains LiFePO 4 .
  • LiMn 2 O 4 can not represent the general formula of "manganese manganate" which is widely used, but should be of the general formula Li 1+x
  • the Mn y M z O k is broadly included, and variously modified LiMn 2 O 4 positive electrode active materials are widely included.
  • LiFePO 4 and LiCoO 2 should also be broadly understood to include modifications through various doping, cladding, etc., which are in accordance with Li x M 1-y M' y (XO 4 ) n and Li 1+, respectively.
  • a positive electrode active material of x M y M' z M" c O 2+n are in accordance with Li x M 1-y M' y (XO 4 ) n and Li 1+, respectively.
  • the positive electrode active material is a substance capable of reversible elution-intercalation of lithium ions
  • a compound such as LiMn 2 O 4 , LiFePO 4 , LiCoO 2 , LiM x PO 4 , LiM x SiO y (where M is a variable valence metal) may preferably be selected. .
  • the positive electrode active material is LiMn 2 O 4 .
  • LiMn 2 O 4 is considered to be one of the most promising cathode materials because of its low cost, sufficient raw materials, environmental friendliness, and good safety.
  • compounds that can be extracted - intercalated with sodium ions can be extracted - compounds intercalated with magnesium ions (such as MgM x O y (where M is a metal, 0.5 ⁇ x ⁇ 3, 2 ⁇ y ⁇ 6 )) and a compound having a similar function capable of eluting-embedding ions or functional groups can be used as the positive electrode active material of the battery of the present invention.
  • sodium ions such as NaVPO 4 F
  • magnesium ions such as MgM x O y (where M is a metal, 0.5 ⁇ x ⁇ 3, 2 ⁇ y ⁇ 6 )
  • a compound having a similar function capable of eluting-embedding ions or functional groups can be used as the positive electrode active material of the battery of the present invention.
  • the positive active material comprises a lithium manganate modified material, and in this case, the first metal ion is a lithium ion.
  • the lithium manganate modified material conforms to the general formula Li 1+x Mn y M z O k , wherein M is selected from Pb, -1 ⁇ x ⁇ 0.5, 1 ⁇ y ⁇ 2.5, 0 ⁇ z ⁇ 0.1, 3 ⁇ k ⁇ 6.
  • M is selected from Pb, -1 ⁇ x ⁇ 0.5, 1 ⁇ y ⁇ 2.5, 0 ⁇ z ⁇ 0.1, 3 ⁇ k ⁇ 6.
  • the lithium manganate modified material has been described in detail in Embodiment 1, and will not be described herein.
  • the surface of the positive electrode active material has a coating layer, and the positive electrode active material includes a lithium ion deintercalation compound, and the coating layer is metal lead and/or lead oxide.
  • the lithium ion delta compound includes at least one of lithium cobaltate, lithium nickelate, and lithium manganate.
  • the mass percentage of lead and positive electrode active material in the metal lead and/or lead oxide ranges from 0.001% to 10%. More preferably, the mass percentage of lead and positive electrode active material in the metal lead and/or lead oxide ranges from 0.1% to 5%. In this way, it is ensured that the positive active material is well protected without affecting the energy density of the positive electrode.
  • lead oxide includes lead monoxide, lead dioxide or lead tetraoxide.
  • the median diameter, specific surface area, and preparation method of the surface of the positive electrode active material having a coating layer are the same as those of the composite positive electrode material of the second embodiment, and will not be further described herein.
  • a positive electrode conductive agent and a positive electrode binder are usually added to enhance the performance of the positive electrode.
  • the conductive agent can reduce the electrical resistance of the overall positive electrode while strengthening the conductance between the positive electrode material particles Electrical pathway.
  • the positive electrode conductive agent is selected from one or more of a conductive polymer, a conductive oxide, a conductive ceramic, activated carbon, graphene, carbon black, graphite, carbon fiber, metal fiber, metal powder, and metal flake.
  • the positive electrode conductive agent accounts for 1% to 15% by mass of the positive electrode material.
  • the positive electrode conductive agent is graphite, and the positive electrode conductive agent accounts for 10% to 14% by mass of the positive electrode material.
  • the binder facilitates uniform bonding of the positive electrode active material and the conductive agent to form a positive electrode.
  • the positive electrode binder may be selected from the group consisting of polyethylene oxide, polypropylene oxide, polyacrylonitrile, polyimide, polyester, polyether, fluorinated polymer, polydivinyl polyethylene glycol, polyethylene glycol. One of diacrylate, polyethylene glycol dimethacrylate, or a mixture and derivative of the above polymers. More preferably, the positive electrode binder is selected from the group consisting of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF) or styrene butadiene rubber (SBR).
  • PTFE polytetrafluoroethylene
  • PVDF polyvinylidene fluoride
  • SBR styrene butadiene rubber
  • the positive electrode further includes a positive electrode current collector supporting the positive electrode active material, and the positive electrode current collector acts only as a carrier for electron conduction and collection, and does not participate in the electrochemical reaction, that is, the positive electrode current collector can stably exist in the electrolysis in the battery operating voltage range.
  • the liquid phase does not substantially cause side reactions, thereby ensuring stable cycle performance of the battery.
  • the material of the cathode current collector is selected from one of a carbon-based material, a metal or an alloy.
  • the carbon-based material is selected from the group consisting of glassy carbon, graphite foil, graphite flakes, foamed carbon, carbon felt, carbon cloth, and carbon fiber.
  • the cathode current collector comprises a carrier and a graphite foil coated on the carrier.
  • the graphite foil is used as a positive electrode current collector, which not only reduces the weight of the positive electrode, but also has good stability of the graphite foil in the aqueous electrolyte, so that the battery has a higher floating charge life, and at the same time, the battery cost is lowered, and the battery is made.
  • a positive electrode current collector which not only reduces the weight of the positive electrode, but also has good stability of the graphite foil in the aqueous electrolyte, so that the battery has a higher floating charge life, and at the same time, the battery cost is lowered, and the battery is made.
  • the carrier itself is electrochemically inert and mainly functions to carry the graphite foil, thereby improving the mechanical properties of the graphite foil.
  • the material of the carrier is selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, polyethylene, polypropylene, polyamide, polyurethane, and polyacrylonitrile. These polymeric materials can be stably present in the positive current collector without participating in the electrochemical reaction, saving weight for the higher energy density output of the battery.
  • the carrier is a nylon mesh, ie a polyamide.
  • the metal includes one of Ni, Al, Fe, Cu, Pb, Ti, Cr, Mo, Co, Ag or the above-mentioned metal which has been passivated.
  • the alloy includes one of stainless steel, carbon steel, Al alloy, Ni alloy, Ti alloy, Cu alloy, Co alloy, Ti-Pt alloy, Pt-Rh alloy or passivated.
  • Stainless steel includes stainless steel mesh, stainless steel foil, and stainless steel models include, but are not limited to, one of stainless steel 304 or stainless steel 316 or stainless steel 316L.
  • the positive current collector is subjected to passivation treatment, and the main purpose thereof is to form a passivated oxide film on the surface of the positive current collector, thereby stably collecting and conducting electrons during charging and discharging of the battery. Function, and will not participate in the battery reaction to ensure stable battery performance.
  • the positive current collector passivation treatment method includes a chemical passivation treatment or an electrochemical passivation treatment.
  • the chemical passivation treatment includes oxidizing the cathode current collector by an oxidizing agent to form a passivation film on the surface of the cathode current collector.
  • the principle of oxidant selection is that the oxidant can form a passivation film on the surface of the positive current collector without dissolving the positive current collector.
  • the oxidizing agent is selected from, but not limited to, concentrated nitric acid or sorghum sulfate (Ce(SO 4 ) 2 ).
  • the electrochemical passivation treatment comprises electrochemically oxidizing the cathode current collector or charging and discharging the battery containing the cathode current collector to form a passivation film on the surface of the cathode current collector.
  • the positive electrode further includes a composite current collector supporting the positive electrode active material, and the composite current collector includes a positive electrode current collector and a conductive film coated on the positive electrode current collector.
  • the conductive film satisfies the requirement that it can be stably present in the aqueous electrolyte, is insoluble in the electrolyte, does not swell, the high voltage cannot be oxidized, and is easily processed into a dense, watertight, and electrically conductive material.
  • the conductive film can protect the positive current collector from corrosion of the positive current collector by the aqueous electrolyte.
  • it is advantageous to reduce the contact internal resistance between the positive electrode sheet and the positive electrode current collector, and to increase the energy of the battery.
  • the conductive film has a thickness of 10 ⁇ m to 2 mm.
  • the cathode current collector has opposite first and second faces.
  • the first surface and the second surface of the cathode current collector are coated with a conductive film.
  • the conductive film contains a polymer as an essential component, and the polymer accounts for 50 to 95% by weight of the conductive film.
  • the polymer is selected from a thermoplastic polymer.
  • the conductive film there are two possible forms: (1) the polymer is a conductive polymer; (2) in addition to the polymer, the conductive film further contains a conductive filler.
  • Conductive polymer materials are required to be electrically conductive but electrochemically inert, i.e., not ionically conductive as a charge transfer medium.
  • conductive polymers include, but are not limited to, polyacetylene, polypyrrole, polythiophene, polyphenylene sulfide, polyaniline, polyacrylonitrile, polyquinoline, polyparaphenylene, and any mixtures thereof.
  • the conductive polymer itself is electrically conductive, but the conductive polymer can also be doped or modified to further increase its electrical conductivity.
  • the conductive polymer is preferably polyaniline, polypyrrole, polythiophene, and polyacetylene from the viewpoint of electrical conductivity and stable use in a battery.
  • conductive fillers require small surface area, difficulty in oxidation, high crystallinity, electrical conductivity, but electrochemical inertness, ie, ion conduction that does not act as a charge transfer medium.
  • Materials for the conductive filler include, but are not limited to, conductive polymers, carbon-based materials, or metal oxides.
  • the mass percentage of the conductive filler in the conductive film ranges from 5 to 50%.
  • the average particle diameter of the conductive filler is not particularly limited, and is usually in the range of 100 nm to 100 ⁇ m.
  • the polymer in the conductive film preferably contains a non-conductive polymer that functions to bond the conductive filler, and the non-conductive polymer enhances the bonding of the conductive filler, improving the reliability of the battery.
  • the non-conductive polymer is a thermoplastic polymer.
  • thermoplastic polymers include, but are not limited to, polyolefins such as polyethylene, polypropylene, polybutene, polyvinyl chloride, polystyrene, polyamide, polycarbonate, polymethyl methacrylate, polyoxymethylene, polyphenylene.
  • polyolefins such as polyethylene, polypropylene, polybutene, polyvinyl chloride, polystyrene, polyamide, polycarbonate, polymethyl methacrylate, polyoxymethylene, polyphenylene.
  • ether, polysulfone, polyethersulfone, styrene butadiene rubber or polyvinylidene fluoride are preferred.
  • polyolefins polyamides and polyvinylidene fluoride.
  • the conductive film is bonded to the positive electrode current collector by hot press lamination, vacuuming or spraying.
  • the electrolyte includes an electrolyte and a solvent.
  • the purpose of the solvent in the electrolyte is to dissolve the electrolyte and ionize the electrolyte in the solvent, eventually generating freely movable cations and anions in the electrolyte.
  • the electrolytic solution is preferably an aqueous electrolytic solution, and the solvent is preferably water.
  • the first metal ion included in the electrolyte can be reversibly extracted-embedded in the positive electrode during charge and discharge. That is, when the battery is charged, the first metal ion is removed from the positive active material Out, entering the electrolyte; when the battery is discharged, the first metal ion in the electrolyte is embedded in the positive active material.
  • the first metal ion is selected from the group consisting of lithium ions, sodium ions or magnesium ions. More preferably, the first metal ion is a lithium ion.
  • the electrolyte further includes a second metal ion which is reduced in deposition to a second metal during charging, and the second metal is oxidized to a second metal ion during discharge.
  • the second metal ion is a zinc ion.
  • the first metal ion is different from the second metal ion.
  • lithium ions and zinc ions are included in the electrolyte. During charge and discharge, lithium ions are intercalated-extracted at the positive electrode, and zinc ions are deposited-dissolved at the negative electrode.
  • the anion in the electrolyte may be any anion that does not substantially affect the positive and negative electrode reactions, and the electrolyte dissolves in the solvent.
  • it may be a sulfate ion, a chloride ion, an acetate ion, a nitrate ion, a phosphate ion, a formate ion, an alkylsulfonate ion, a mixture thereof, or the like.
  • the concentration of each ion in the electrolyte can be changed according to different conditions of different electrolytes, solvents, and application fields of the battery.
  • the concentration of the first metal ion is 0.1 to 10 mol/L.
  • the concentration of the second metal ion in the electrolytic solution is 0.5 to 15 mol/L.
  • the concentration of the anion in the electrolytic solution is from 0.5 to 12 mol/L.
  • the pH of the electrolyte ranges from 3 to 7.
  • the pH range can be adjusted by a buffer. If the pH of the electrolyte is too high, it may affect the concentration of zinc ions in the electrolyte. If the pH of the electrolyte is too low, the corrosion of the electrode material may be aggravated. Keeping the pH range of the electrolyte at 3 to 7 can effectively ensure the concentration of metal ions in the electrolyte and avoid electrode corrosion.
  • the negative electrode of the battery includes a negative electrode active material, and the negative electrode active material is capable of undergoing a reversible reduction deposition-oxidation dissolution reaction.
  • the second metal ion can be reduced to the second metal on the side of the negative electrode active material and deposited on the negative electrode active material.
  • the second metal on the negative active material is reoxidized into the second metal ion into the electrolyte.
  • the second metal ion is a zinc ion.
  • the negative electrode of the battery can be divided into the following two different forms depending on the structure and function:
  • the negative electrode includes a negative current collector and a negative current collector A negative electrode active material on the body.
  • the anode current collector acts as a carrier for electron conduction and collection and does not participate in the electrochemical reaction.
  • the material of the anode current collector is selected from at least one of metal Ni, Cu, Ag, Pb, Mn, Sn, Fe, Al or passivated metal, or elemental silicon, or carbon-based material; wherein, carbon-based Materials include graphite materials such as commercial graphite pressed foils in which the weight ratio of graphite ranges from 90 to 100%.
  • the material of the anode current collector may also be selected from stainless steel or passivated stainless steel.
  • Stainless steel includes, but is not limited to, stainless steel mesh and stainless steel foil.
  • stainless steel models can be 300 series stainless steel, such as stainless steel 304 or stainless steel 316 or stainless steel 316L.
  • the anode current collector is a brass foil.
  • the negative electrode active material exists in the form of a sheet or a powder.
  • the negative electrode active material forms a composite layer with the negative electrode current collector.
  • the negative electrode active material powder is slurried, and then the slurry is coated on the negative electrode current collector to form a negative electrode.
  • the negative electrode conductive agent and the negative electrode binder may be added as needed to improve the performance of the negative electrode.
  • the negative electrode active material is zinc.
  • the negative electrode comprises a brass foil and a zinc foil
  • the brass foil acts as a negative electrode current collector
  • the zinc foil acts as a negative electrode active material and can participate in the negative electrode reaction.
  • the negative electrode active material is directly used as the negative electrode, that is, the negative electrode active material also serves as the negative electrode current collector.
  • the negative electrode active material may have dendritic problems during charge and discharge of the battery.
  • the problem of dendrites of the negative electrode active material is improved by having a lead-containing substance on the surface of the negative electrode active material or/and in the electrolytic solution.
  • the total content of lead in the surface of the negative electrode active material or/and the lead-containing substance in the electrolytic solution is not more than 1000 ppm with respect to the mass ratio of the battery.
  • the lead-containing substance includes at least one of metal lead, lead sulfate, and lead oxide.
  • the lead-containing material is present on the surface of the negative active material. More preferably, the lead-containing substance in the surface of the negative electrode active material includes lead metal.
  • the "anode active material surface” in the present invention means the negative electrode active material.
  • a lead-containing substance on the surface of the negative electrode active material There are two understandings: when the lead-containing substance (single substance or compound) is added to the negative electrode active material in a powder form, the powder particles of the lead-containing substance are located in the plane of the surface of the negative electrode active material; When the lead-containing substance is added to the negative electrode active material by plating or coating, the plating or coating of the lead-containing substance is located on the surface of the surface of the negative electrode active material.
  • the mass ratio of the lead in the lead-containing substance on the surface of the negative electrode active material to the negative electrode active material is not more than 1000 ppm. That is, the "lead on the surface of the negative electrode active material" means the total amount of lead contained therein, regardless of whether the lead-containing substance is any one or more of a single element of a lead metal or a compound thereof.
  • the method for adding the lead-containing substance to the negative electrode active material may be a physical method or a chemical method including, but not limited to, mechanical mixing, mechanical coating, vacuum plating onto the negative electrode active material, or magnetron sputtering onto the negative electrode active material; Chemical methods include, but are not limited to, electrochemical plating onto a negative active material, and the like.
  • the lead-containing material in the electrolyte includes lead ions.
  • the lead-containing substance When a lead-containing substance is added to the electrolytic solution, dendrites of the negative electrode active material can be effectively suppressed.
  • the lead-containing substance is added to the electrolyte, and lead ions enter the electrolyte. Even if the lead-containing substance is initially insoluble in the electrolyte, it will slowly dissolve to form lead ions during charging and discharging.
  • the lead ions in the electrolyte can promote the deposition-dissolution kinetics of the second metal ions on the surface of the anode active material, stabilize the deposition process of the second metal ions, and change the surface of the second metal ions on the anode active material.
  • the direction of the crystal face is deposited so that the second metal ion obtains a uniform deposited layer while suppressing the dendrite growth of the negative electrode active material.
  • the mass ratio of lead to electrolyte in the lead-containing substance in the electrolyte is not less than 10 ppm.
  • lead in the lead-containing substance in the electrolyte means lead ion;
  • in the lead-containing substance in the electrolyte Lead refers to the total amount of lead in the lead-containing substance that is insoluble and the amount of lead ions dissolved in the electrolyte.
  • the method of adding a lead-containing substance to the electrolyte includes, but is not limited to, directly adding to the electrolyte, or The suspension is added to the membrane as a droplet. More preferably, these additives are directly added to the electrolyte, and then the electrolyte is dropped onto the separator.
  • the surface of the negative electrode active material and the electrolyte contain lead-containing substances at the same time. More preferably, the lead-containing substance in the surface of the negative electrode active material includes lead metal and the lead-containing substance in the electrolytic solution includes lead ions.
  • the mass ratio of lead to electrolyte in the lead-containing substance in the electrolyte is not less than 10 ppm.
  • the battery further comprises an additive cerium compound, which is added to the negative electrode or the electrolyte or the negative electrode and the electrolyte simultaneously.
  • the cerium compound is selected from the group consisting of antimony trioxide and/or cerium nitrate.
  • the dose of the ruthenium compound used in the negative electrode is preferably as follows:
  • antimony trioxide When antimony trioxide is used alone, antimony trioxide accounts for 0.1 to 10% of the total weight of the negative electrode.
  • cerium nitrate When cerium nitrate is used alone, cerium nitrate accounts for 0.1 to 10% by weight based on the total weight of the negative electrode.
  • the dosage of the cerium compound used in the electrolyte is preferably as follows:
  • antimony trioxide When antimony trioxide is used alone, antimony trioxide accounts for 0.01 to 5% of the total weight of the electrolyte.
  • cerium nitrate When cerium nitrate is used alone, cerium nitrate accounts for 0.01 to 5% by weight based on the total weight of the electrolyte.
  • a ruthenium compound is simultaneously added to the negative electrode and the electrolyte.
  • the ruthenium compound When the ruthenium compound is added to the negative electrode and/or the electrolyte, depending on the morphological structure of the negative electrode and the electrolyte, it may be selected from different ways of addition, similar to the method of adding a lead-containing substance.
  • the diaphragm can avoid short circuits caused by the connection of positive and negative electrodes caused by other unexpected factors.
  • the separator is not particularly required as long as it is a separator that allows the electrolyte to pass through and is electrically insulated.
  • Various separators used in organic lithium ion batteries can be applied to the present invention.
  • the separator may also be other materials such as microporous ceramic separators.
  • the invention also provides a battery pack comprising a plurality of the above batteries, In general, two or more batteries are connected in series, in parallel, or a combination thereof to produce a battery pack.
  • the capacity and voltage of the battery pack can be freely adjusted by series and/or parallel connection of the batteries.
  • a battery or a battery pack constructed in accordance with the present invention can be used as a power source for vehicles and transportation equipment such as power trains, and as a fixed/installable power source such as an uninterruptible power source.
  • the present invention also discloses a battery comprising a positive electrode, a negative electrode and an electrolyte, the positive electrode comprising a positive electrode active material and a positive electrode current collector, and the positive electrode active material comprising a lithium manganate modified material.
  • the electrolyte is an aqueous solution.
  • the positive active material participates in the electrochemical reaction.
  • the lithium manganate modified material in the positive active material conforms to the general formula Li 1+x Mn y M z O k , wherein M is selected from pb, -1 ⁇ x ⁇ 0.5, 1 ⁇ y ⁇ 2.5, 0 ⁇ z ⁇ 0.1, and 3 ⁇ k ⁇ 6.
  • the lithium manganate modified material has been introduced in the first embodiment, and will not be described herein.
  • a positive electrode conductive agent and a positive electrode binder are usually added to enhance the performance of the positive electrode.
  • the positive electrode conductive agent and the positive electrode binder have been described in the third embodiment, and will not be described herein.
  • the positive active material is supported on the positive current collector, and the positive current collector acts as a carrier for electron conduction and collection, and does not participate in the electrochemical reaction, that is, in the operating voltage range of the battery, the positive current collector can stably exist in the electrolyte without substantially occurring. Side reaction to ensure stable cycle performance of the battery.
  • Embodiment 4 the battery in Embodiment 4 will be further described by a preferred embodiment.
  • a battery comprising a positive electrode, a negative electrode and an electrolyte, a positive electrode comprising a positive electrode active material and a positive electrode current collector, and a positive electrode active material comprising a lithium manganate modified material as described above.
  • the electrolyte is an aqueous solution, and the electrolyte further includes a first metal ion and a second metal ion.
  • the first metal ion can be reversibly extracted-embedded in the positive electrode, the second metal ion can be reducedly deposited as a second metal in the negative electrode, and the second metal can be reversibly oxidized and dissolved into the second metal ion, the first metal ion It is a lithium ion.
  • the working principle of the battery is: when the battery is charged, lithium ions are extracted from the positive electrode active material lithium manganate modified material, and electrons are released; electrons reach the negative electrode of the battery through the external circuit, and the second metal ion in the electrolyte obtains electrons on the negative electrode. Being reduced and deposited on the negative electrode Forming a second metal; when discharging, the second metal at the negative electrode is oxidized, and the lost electrons are converted into the second metal ions into the electrolyte; the electrons reach the positive electrode through the external circuit, and the positive active material receives the electrons, and the electrolyte
  • the first metal ion lithium ion is embedded in the positive electrode active material.
  • the first metal ion lithium ion included in the electrolyte can be reversibly extracted-embedded in the positive electrode during charge and discharge. That is, when the battery is charged, the first metal ion lithium ion is extracted from the positive electrode active material lithium manganate modified material and enters the electrolyte; when the battery is discharged, the first metal ion lithium ion in the electrolyte is embedded in the positive electrode active material manganese acid.
  • lithium modified materials are lithium modified materials.
  • the second metal ion is a zinc ion.
  • the anion in the electrolyte may be any anion that does not substantially affect the positive and negative electrode reactions, and the electrolyte dissolves in the solvent.
  • it may be a sulfate ion, a chloride ion, an acetate ion, a nitrate ion, a phosphate ion, a formate ion, an alkylsulfonate ion, a mixture thereof, or the like.
  • the concentration of each ion in the electrolyte can be changed according to different conditions of different electrolytes, solvents, and application fields of the battery.
  • the concentration of the first metal ion lithium ion is 0.1 to 10 mol/L.
  • the concentration of the second metal ion in the electrolytic solution is 0.5 to 15 mol/L.
  • the concentration of the anion in the electrolytic solution is from 0.5 to 12 mol/L.
  • the pH of the electrolyte ranges from 2 to 8.
  • the pH range can be adjusted by a buffer. If the pH of the electrolyte is too high, it may affect the concentration of zinc ions in the electrolyte. If the pH of the electrolyte is too low, the corrosion of the electrode material will be accelerated. Keeping the pH range of the electrolyte at 2-8 can effectively ensure the concentration of metal ions in the electrolyte and avoid electrode corrosion.
  • the negative electrode can be in three different forms depending on its structure and function:
  • the negative electrode includes only the negative electrode current collector, and the negative electrode current collector serves only as a carrier for electron conduction and collection, and does not participate in the electrochemical reaction.
  • the anode current collector is a copper foil, a stainless steel mesh, a stainless steel foil or a graphite foil.
  • the negative electrode includes only the negative electrode active material, and the negative electrode active material simultaneously serves as the negative electrode current collector.
  • the second metal ion is zinc ion and the negative electrode is zinc foil.
  • the zinc foil can participate in the negative electrode reaction.
  • the negative electrode includes a negative electrode active material and a negative electrode current collector, and the negative electrode active material is supported on the negative electrode current collector.
  • the negative electrode active material is the same as the second metal.
  • the negative electrode active material is also metal Zn.
  • the negative electrode includes a brass foil and a zinc foil, the brass foil serves as a negative electrode current collector, and the zinc foil corresponds to the negative electrode active material and can participate in the negative electrode reaction.
  • the negative electrode active material exists in the form of a sheet or a powder.
  • the negative electrode active material When the negative electrode active material is in the form of a sheet, the negative electrode active material forms a composite layer with the negative electrode current collector.
  • the anode active material is a powder
  • the second metal powder is slurried, and then the slurry is coated on the anode current collector to form a cathode.
  • the negative electrode conductive agent and the negative electrode binder are added as needed to improve the performance of the negative electrode.
  • the negative electrode active material may have dendritic problems during charge and discharge of the battery.
  • the problem of dendrites of the negative electrode active material is improved by having a lead-containing substance on the surface of the negative electrode active material or/and in the electrolytic solution.
  • the lead-containing substance is present on the surface of the negative electrode active material or/and the electrolyte in the third embodiment, and will not be described herein.
  • the diaphragm can avoid short circuits caused by the connection of positive and negative electrodes caused by other unexpected factors.
  • the separator is not particularly required as long as it is a separator that allows the electrolyte to pass through and is electrically insulated.
  • Various separators used in organic lithium ion batteries can be applied to the present invention.
  • the separator may also be other materials such as microporous ceramic separators.
  • the lithium manganate modified material provided by the invention has good compatibility with the aqueous electrolyte, and the side reaction at the interface between the lithium manganate modified material and the aqueous electrolyte is suppressed. Further, the battery using the lithium manganate modified material as the positive electrode active material has obvious improvement in cycle, self-discharge and floatation performance, so that the battery provided by the invention has good commercial application prospects.
  • the present invention also provides a battery pack comprising a plurality of the above-described batteries, in particular, a battery pack is produced by connecting two or more batteries in series, in parallel, or a combination thereof.
  • the capacity and voltage of the battery pack can be freely adjusted by series and/or parallel connection of the batteries.
  • a battery provided according to the present invention or a battery pack constructed of the battery can be used as a vehicle and a transportation device It is used as a power source for power locomotives and as a fixed/installable power source such as an uninterruptible power supply.
  • the invention also discloses a battery comprising a positive electrode, a negative electrode and an electrolyte, the positive electrode comprising a composite positive electrode material and a positive electrode current collector, the composite positive electrode material comprising a positive electrode active material and a coating layer, and the positive electrode active material comprising a lithium ion deintercalation compound,
  • the coating is metallic lead and/or lead oxide.
  • the electrolyte is an aqueous solution.
  • the mass percentage of lead in the metal lead and/or lead oxide to the positive electrode active material ranges from 0.001% to 10%.
  • Lead oxide includes at least one of lead monoxide, lead dioxide, and lead tetraoxide.
  • the positive active material participates in the electrochemical reaction.
  • the composite positive electrode material has been introduced in the second embodiment, and will not be described herein.
  • a positive electrode conductive agent and a positive electrode binder are usually added to improve the performance of the positive electrode.
  • the positive electrode conductive agent and the positive electrode binder have been described in the third embodiment, and will not be described herein.
  • the composite positive electrode material is supported on the positive electrode current collector, and the positive electrode current collector acts as a carrier for electron conduction and collection, and does not participate in the electrochemical reaction, that is, in the operating voltage range of the battery, the positive electrode current collector can stably exist in the electrolyte without substantially occurring. Side reaction to ensure stable cycle performance of the battery.
  • the positive current collector is the same as the positive current collector in the third embodiment, and will not be described herein.
  • Embodiment 5 the battery of Embodiment 5 will be further described by a preferred embodiment.
  • a battery comprising a positive electrode, a negative electrode and an electrolyte, the positive electrode comprising a composite positive electrode material and a positive electrode current collector, the composite positive electrode material being as described above.
  • the electrolyte is an aqueous solution, and the electrolyte further includes a first metal ion and a second metal ion.
  • the first metal ion can be reversibly extracted-embedded in the positive electrode
  • the second metal ion can be reducedly deposited as a second metal in the negative electrode
  • the second metal can be reversibly oxidized and dissolved into the second metal ion, the first metal ion It is a lithium ion.
  • the working principle of the battery is: when the battery is charged, the lithium ion deintercalation compound of the positive active material desorbs lithium ions and emits electrons; the electrons reach the negative electrode of the battery through the external circuit, and the second metal ion in the electrolyte obtains electrons on the negative electrode. Reducing and depositing on the negative electrode to form a second metal; when discharging, the second metal at the negative electrode is oxidized, and the electrons are lost to The second metal ion enters the electrolyte; the electron reaches the positive electrode through the external circuit, the positive active material receives electrons to be reduced, and the first metal ion lithium ion in the electrolyte is embedded in the positive electrode active material.
  • the first metal ion lithium ion included in the electrolyte can be reversibly extracted-embedded in the positive electrode during charge and discharge. That is, when the battery is charged, the first metal ion lithium ion is separated from the positive electrode active material lithium ion deintercalation compound and enters the electrolyte; when the battery is discharged, the first metal ion lithium ion in the electrolyte is inserted into the positive electrode active material lithium ion off Embedded in the compound.
  • the second metal ion is a zinc ion.
  • the anion in the electrolyte may be any anion that does not substantially affect the positive and negative electrode reactions, and the electrolyte dissolves in the solvent.
  • it may be a sulfate ion, a chloride ion, an acetate ion, a nitrate ion, a phosphate ion, a formate ion, an alkylsulfonate ion, a mixture thereof, or the like.
  • the concentration of each ion in the electrolyte can be changed according to different conditions of different electrolytes, solvents, and application fields of the battery.
  • the concentration of the first metal ion lithium ion is 0.1 to 10 mol/L.
  • the concentration of the second metal ion in the electrolytic solution is 0.5 to 15 mol/L.
  • the concentration of the anion in the electrolytic solution is from 0.5 to 12 mol/L.
  • the pH of the electrolyte ranges from 2 to 8.
  • the pH range can be adjusted by a buffer. If the pH of the electrolyte is too high, it may affect the concentration of zinc ions in the electrolyte. If the pH of the electrolyte is too low, the corrosion of the electrode material will be accelerated. Keeping the pH range of the electrolyte at 2-8 can effectively ensure the concentration of metal ions in the electrolyte and avoid electrode corrosion.
  • the negative electrode is the same as the negative electrode in the fourth embodiment, and will not be described again here.
  • the negative electrode active material may have dendritic problems during charge and discharge of the battery.
  • the problem of dendrites of the negative electrode active material is improved by having a lead-containing substance on the surface of the negative electrode active material or/and in the electrolytic solution.
  • the lead-containing substance is present on the surface of the negative electrode active material or/and in the electrolytic solution, and is not described in detail herein.
  • the diaphragm can avoid short circuits caused by the connection of positive and negative electrodes caused by other unexpected factors.
  • the separator is not particularly required as long as it is a separator that allows the electrolyte to pass through and is electrically insulated.
  • Various separators used in organic lithium ion batteries can be applied to the present invention.
  • the separator may also be other materials such as microporous ceramic separators.
  • the composite positive electrode material provided by the invention has good compatibility with the aqueous electrolyte solution, and the side reaction at the interface between the composite positive electrode material and the aqueous electrolyte solution is suppressed. Further, the battery using the composite positive electrode material as the positive electrode active material has significantly improved cycle, self-discharge and floatation performance, so that the battery provided by the invention has good commercial application prospects.
  • the present invention also provides a battery pack comprising a plurality of the above-described batteries, in particular, a battery pack is produced by connecting two or more batteries in series, in parallel, or a combination thereof.
  • the capacity and voltage of the battery pack can be freely adjusted by series and/or parallel connection of the batteries.
  • a battery or a battery pack constructed in accordance with the present invention can be used as a power source for vehicles and transportation means such as trains, and as a fixed/installable power source such as an uninterruptible power source.
  • the positive current collector is a composite material of a PE conductive film and a nickel-plated carbon steel.
  • the positive electrode slurry is coated on the positive electrode current collector to form an active material layer, which is then pressed into a positive electrode sheet, and the positive electrode sheet has a thickness of 0.4. Mm, the surface active density of the positive electrode active material was 750 g/m 2 .
  • the negative electrode includes a 55 ⁇ m thick zinc foil, and the surface of the zinc foil has a lead plating layer, and the mass ratio of the lead plating layer to the zinc foil is 700 ppm.
  • the electrolytic solution was a mixed aqueous solution of 2 mol/L of zinc sulfate and 1 mol/L of lithium sulfate.
  • the diaphragm is AGM glass fiber, and the diaphragm and anode are equivalent in size to the positive electrode.
  • the assembled battery had a theoretical capacity of about 5 Ah, which was designated as A1.
  • Example 1-1 The difference from Example 1-1 was that the mass ratio of the lead plating layer on the surface of the zinc foil to the zinc foil was 300 ppm, and the other portions were the same as those in Example 1-1, and it was designated as A2.
  • Example 1-1 The difference from Example 1-1 was that the mass ratio of the lead plating layer on the surface of the zinc foil to the zinc foil was 1000 ppm, and the other portions were the same as those in Example 1-1, which was designated as A3.
  • Example 1-1 The difference from Example 1-1 was that the mass ratio of the lead plating layer on the surface of the zinc foil to the zinc foil was 100 ppm, and the other portions were the same as those in Example 1-1, and referred to as A4.
  • the concentration of zinc sulfate and lithium sulfate in the electrolyte are 2mol / L and 1mol / L, respectively, lead sulfate in the electrolyte The concentration is 450 ppm.
  • the prepared electrolyte and the 2.5 cm 2 zinc foil working electrode, the foamed nickel counter electrode and the saturated calomel reference electrode were combined to form a three-electrode system battery, which was designated as A5.
  • Example 1-5 The difference from Example 1-5 was that the concentration of lead sulfate added to the electrolytic solution was 150 ppm, and the other portions were the same as those in Examples 1-5, which were designated as A6.
  • Example 1-5 The difference from Example 1-5 was that the concentration of lead sulfate added to the electrolytic solution was 75 ppm, and the other portions were the same as those in Examples 1-5, which were designated as A7.
  • Example 1-5 The difference from Example 1-5 was that the concentration of lead sulfate added to the electrolytic solution was 10 ppm, and the other portions were the same as those of Examples 1-5, and were designated as A8.
  • Example 1-5 The difference from Example 1-5 was that the concentration of lead sulfate added to the electrolytic solution was 1000 ppm, and the other portions were the same as those in Examples 1-5, which were designated as A9.
  • Example 1-1 The difference from Example 1-1 was that the surface of the negative electrode active material zinc foil of the battery was free of lead plating, and the other portions were the same as those of Example 1-1, and it was designated as D1.
  • Example 1-1 The difference from Example 1-1 was that the mass ratio of the lead plating layer on the surface of the negative electrode active material zinc foil of the battery to the zinc foil was 1,500 ppm, and the other portions were the same as those in Example 1-1, and it was designated as D2.
  • Example 1-5 The difference from Example 1-5 was that lead sulfate was not added to the electrolyte of the three-electrode system battery, and the other portions were the same as those of Examples 1-5, which were designated as D3.
  • the batteries A1-A4 and D1-D2 were subjected to constant current 100DOD% cycle charge and discharge at a rate of 0.2 C at 25 ° C, and the voltage range was 1.4-2.1 V.
  • Table 1 shows the capacity retention ratio with respect to the first discharge capacity when the batteries A1-A4 and D1-D2 were cycled 75 times. It can be seen from Table 1 that after the surface of the negative electrode active material of the battery is plated with lead, the cycle performance of the battery is improved, especially when the mass ratio of lead to zinc foil is not more than 1000 ppm, and the cycle performance of the battery is greatly improved.
  • Fig. 1 is a graph showing the relationship between the discharge capacity of the batteries A1 and D1, the internal resistance of the battery, and the number of cycles. It can also be seen from Fig. 1 that the cycle life of the battery A1 is greatly improved compared to the battery D1.
  • the discharge capacity retention rate is about 80%, and after D1 is cycled 50 times, the internal resistance of the battery is obviously increased, and the battery capacity is rapidly decreased.
  • the discharge capacity retention rate is only There are about 16%.
  • the three-electrode system batteries A5-A9 and D3 were subjected to a one-hour chronoamperometry at an overvoltage of -120 mV.
  • Figure 2 is a plot of absolute current density versus time for the working electrode of a three-electrode system cell in A5 and D3.
  • the zinc working electrode acts as a cathode and its absolute current density is related to the amount of metal deposited on the zinc electrode. It can be seen from the figure that the current density of the zinc electrodes of D3 and A5 after 1 hour test is very close, which indicates that the metal on the zinc electrode of D3 and A5 is within 1 hour. The amount of deposition is equivalent. However, the current density of the zinc electrode in A5 is stable at 150s, and the current density of the zinc electrode in D3 is stable after about 1500s, which indicates that lead ions can stabilize the deposition process of zinc ions. A similar phenomenon can be observed on A6-A9. As long as lead ions are added to the electrolyte, the cathode current density can be quickly stabilized, indicating that trace amounts of lead ions can promote the deposition process of zinc ions.
  • the three-electrode system batteries A5-A9 and D3 were tested for 1 hour chronoamperometry, the tested working electrode was washed with deionized water, dried at room temperature, and the working electrode was characterized by SEM. Microscopic appearance.
  • Figures 3-6 show SEM images of the working electrodes of A5-A7 and D3 after one hour chronoamperometry. It can be seen from the figure that when lead sulfate is added to the electrolyte, the deposition layer of zinc ions on the anode zinc electrode is uniform, and the deposited metal particles are small; while the electrolyte without lead sulfate is added, the deposition layer of zinc ions is uneven. Some parts of the zinc electrode have no deposited layer, some parts are thick, and there are obvious dendrites of large particles, which indicates that lead ions can change the deposition crystal plane of zinc ions on the zinc electrode and make the deposition layer more uniform. .
  • the lead-containing substance when the lead-containing substance is present on the surface of the negative electrode active material or in the electrolyte, the dendrite of the negative electrode active material is effectively suppressed, and the cycle performance and discharge capacity of the battery can be significantly improved.
  • the lithium manganate modified material of the present embodiment has a molecular formula of LiMn 2 Pb 0.05 O 4 .
  • the uniformly mixed product is sent to a sintering furnace for heat treatment, and heat-treated at 700 to 850 ° C for 15 to 30 hours in an air atmosphere.
  • a lithium manganate modified material LiMn 2 Pb 0.05 O 4 was obtained , which was designated as a1.
  • the lithium manganate modified material of the present embodiment has a molecular formula of LiMn 2 Pb 0.01 O 4 .
  • the uniformly mixed product is sent to a sintering furnace and heat-treated at 700 to 850 ° C for 15 to 30 hours in an air atmosphere.
  • a lithium manganate modified material LiMn 2 Pb 0.01 O 4 was obtained , which was designated as a2.
  • the lithium manganate modified material of the present embodiment has a molecular formula of LiMn 2 Pb 0.005 O 4 .
  • the uniformly mixed product is sent to a sintering furnace and heat-treated at 700 to 850 ° C for 15 to 30 hours in an air atmosphere.
  • a lithium manganate modified material LiMn 2 Pb 0.005 O 4 was obtained , which was designated as a3.
  • the lithium manganate modified material of the present embodiment has a molecular formula of LiMn 2 Pb 0.001 O 4 .
  • the uniformly mixed product is sent to a sintering furnace and heat-treated at 700 to 850 ° C for 15 to 30 hours in an air atmosphere.
  • a lithium manganate modified material LiMn 2 Pb 0.001 O 4 was obtained , which was designated as a4.
  • lithium manganate was not modified, and the lithium manganate material had a molecular formula of LiMn 2 O 4 and was designated as d1.
  • the positive electrode slurry was coated on a positive electrode current collector graphite foil to form an active material layer, and the surface density of the positive electrode active material was 20 mg/cm 2 .
  • the negative electrode included a 50 ⁇ m thick negative electrode active material zinc foil and a 20 ⁇ m thick negative electrode current collector brass foil.
  • the AGM film serves as a separator.
  • a certain amount of zinc sulfate and lithium sulfate were weighed and dissolved in water to prepare an electrolyte having a zinc sulfate concentration of 2 mol/L and a lithium sulfate concentration of 1 mol/L.
  • the positive electrode, the negative electrode and the separator were assembled into a battery cell, placed in a casing, and then an electrolyte was injected, sealed, and assembled into a battery having a capacity of 7 mAh, which was designated as B1.
  • Example 2-6 the positive electrode active material was a lithium manganate modified material a2, and the remaining structure and preparation method of the battery were the same as those in Example 2-5, and assembled into a battery having a capacity of 7 mAh, which was designated as B2.
  • the positive electrode active material was a lithium manganate modified material a3, and the remaining structure and preparation method of the battery were the same as those in Example 2-5, and assembled into a battery having a capacity of 7 mAh, which was designated as B3.
  • the positive electrode active material was a lithium manganate modified material a4, and the remaining structure and preparation method of the battery were the same as those in Example 2-5, and assembled into a battery having a capacity of 7 mAh, which was designated as B4.
  • the positive electrode active material was a lithium manganate material d1
  • the remaining structure and preparation method of the battery were the same as those in Example 2-5, and assembled into a battery having a capacity of 7 mAh, which was designated as S1.
  • the batteries in Examples 2-5 to 2-8 and Comparative Example 2-2 were subjected to a charge and discharge cycle test at a temperature of 1 C at a voltage of 1.4 V to 2.1 V at a normal temperature.
  • Table 1 shows the capacity retention ratio with respect to the first discharge capacity when the batteries B2-B4 and s1 were cycled 100 times, 200 times, and 300 times, respectively, at 1C.
  • the batteries in Examples 2-5 to 2-8 and Comparative Example 2-2 were charged at a constant current of 0.2 C. After charging to 2.1 V, the battery was subjected to constant voltage charging, and the current was limited to 0.2 C until the current was reduced to 0. 02 C. . The battery was allowed to stand at 60 ° C for one day, and the battery was tested for capacity loss after the battery was cooled to room temperature; the battery was allowed to stand at 60 ° C for seven days, and the battery was tested for capacity loss after the battery was cooled to room temperature.
  • Table 2 shows the capacity loss of the batteries B1-B4 and S1 which were left at 60 ° C for one day, left at 60 ° C for two days, and left at 60 ° C for three days.
  • the batteries in Examples 2-5 to 2-8 and Comparative Example 2-2 were charged at a constant current of 0.2 C at room temperature, and then charged to 2.0 V, and then the battery was floated at 60 ° C for 2.0 h at 168 h (one week). Test the float current and float capacity of the battery.
  • Table 3 shows the float charge flow and float charge capacity of the batteries B1-B4 and S1 floated at 60 ° C for 168 h.
  • the positive electrode active material was a lithium manganate modified material a4, and the remaining structure of the positive electrode and the preparation method were the same as those in Examples 2-5.
  • the negative electrode includes a 50 ⁇ m thick negative electrode active material zinc foil, and the surface of the zinc foil has a lead plating layer, and the mass ratio of the lead plating layer to the zinc foil is 700 ppm.
  • the AGM film serves as a separator.
  • a certain amount of zinc sulfate and lithium sulfate were weighed and dissolved in water to prepare an electrolyte having a zinc sulfate concentration of 2 mol/L and a lithium sulfate concentration of 1 mol/L.
  • the positive electrode, the negative electrode, and the separator were assembled into a battery cell, and placed in a casing, and then the electrolyte was injected, sealed, and assembled into a battery having a capacity of 7 mAh, which was designated as B5.
  • Example 2-10 the surface of the negative electrode zinc foil had a lead-plated layer, and the mass ratio of the quality of the lead-plated layer to the zinc foil was 300 ppm.
  • the remaining composition and preparation method of the battery were the same as in Examples 2-9, and assembled into a battery having a capacity of 7 mAh, which was designated as B6.
  • Example 2-11 the surface of the negative electrode zinc foil had a lead-plated layer, and the mass ratio of the quality of the lead-plated layer to the zinc foil was 100 ppm.
  • the rest of the battery was constructed and prepared in the same manner as in Examples 2-9, and assembled into a battery having a capacity of 7 mAh, which was designated as B7.
  • Example 2-12 lead sulfate was added to the electrolytic solution, and the concentration of lead sulfate was 150 ppm.
  • the remaining composition and preparation method of the battery were the same as those in Examples 2-9, and assembled into a battery having a capacity of 7 mAh, which was designated as B8.
  • the batteries B5-B8 of Examples 2-9 to 2-12 were subjected to a charge and discharge cycle test at a normal temperature at a voltage of 1.4 V to 2.1 V at a rate of 1 C.
  • the battery B5-B8 has a capacity retention rate higher than that of the battery B4 100 times. This result indicates that when a lead-containing substance is present on the surface of the negative electrode active material or in the electrolytic solution, dendrites of the negative electrode active material are effectively suppressed, and the cycle performance of the battery is further improved.
  • the positive active material is lithium manganate LiMn 2 O 4
  • the coating layer is lead
  • the composite positive electrode material is lead-coated lithium manganate, wherein the mass percentage of lead and lithium manganate It is 5%.
  • Raw material Lead acetate and lithium manganate were weighed at a mass ratio of 5:100, mixed in deionized water, and stirred. The coating material is uniformly coated on the surface of the positive electrode active material lithium manganate particles, and the uniformly mixed product is dried, and the dried solid material is sintered at 400-650 ° C for 15-30 hours.
  • the positive active material is lithium manganate LiM n 2O 4
  • the coating layer is lead
  • the composite positive electrode material is lead-coated lithium manganate, wherein the mass percentage of lead and lithium manganate It is 1%.
  • Raw material Lead acetate and lithium manganate were weighed at a mass ratio of 1:100, mixed in deionized water, and stirred. The coating material is uniformly coated on the surface of the positive electrode active material lithium manganate particles, and the uniformly mixed product is dried, and the dried solid material is sintered at 400-650 ° C for 15-30 hours.
  • the positive active material is lithium manganate LiMn 2 O 4
  • the coating layer is lead
  • the composite positive electrode material is lead-coated lithium manganate, wherein the mass percentage of lead and lithium manganate It is 0.5%.
  • Raw material lead acetate and lithium manganate are weighed according to the mass ratio of 0.5:100, and deionized Mix in water and stir.
  • the coating material is uniformly coated on the surface of the positive electrode active material lithium manganate particles, and the uniformly mixed product is dried, and the dried solid material is sintered at 400-650 ° C for 15-30 hours.
  • the positive active material is lithium manganate LiMn 2 O 4
  • the coating layer is lead
  • the composite positive electrode material is lead-coated lithium manganate, wherein the mass percentage of lead and lithium manganate It is 0.1%.
  • Raw material Lead acetate and lithium manganate were weighed according to a mass ratio of 0.1:100, and mixed in deionized water and stirred. The coating material is uniformly coated on the surface of the positive electrode active material lithium manganate particles, and the uniformly mixed product is dried, and the dried solid material is sintered at 400-650 ° C for 15-30 hours.
  • the positive electrode active material was lithium manganate LiMn 2 O 4 , and lithium manganate was not coated.
  • the positive electrode slurry was coated on a positive electrode current collector graphite foil to form an active material layer, and the surface density of the positive electrode active material was 20 mg/cm 2 .
  • the negative electrode included a 50 ⁇ m thick negative electrode active material zinc foil and a 20 ⁇ m thick negative electrode current collector brass foil.
  • the AGM film serves as a separator.
  • a certain amount of zinc sulfate and lithium sulfate were weighed and dissolved in water to prepare an electrolyte having a zinc sulfate concentration of 2 mol/L and a lithium sulfate concentration of 1 mol/L.
  • the positive electrode, the negative electrode, and the separator were assembled into a battery cell, placed in a casing, and then an electrolyte was injected, sealed, and assembled into a battery having a capacity of 7 mAh, which was designated as C1.
  • Example 3-2 The composite cathode material of Example 3-2 was used in Examples 3-6, and the remaining structure and preparation method of the battery were the same as those in Example 3-5, and assembled into a battery having a capacity of 7 mAh, which was designated as C2.
  • Example 3-3 The composite cathode material of Example 3-3 was used in Examples 3 to 7.
  • the remaining structure and preparation method of the battery were the same as those in Example 3-5, and assembled into a battery having a capacity of 7 mAh, which was designated as C3.
  • the composite cathode materials of Examples 3-4 were used in Examples 3-8, and the remaining structure and preparation method of the batteries were the same as those in Examples 3-5, and assembled into a battery having a capacity of 7 mAh, which was designated as C4.
  • Comparative Example 3-2 the composite positive electrode material of Comparative Example 3-1 was used, and the remaining structure and preparation method of the battery were the same as those of Examples 3-5, and assembled into a battery having a capacity of 7 mAh, which was designated as E1.
  • the batteries in Examples 3-5 to 3-8 and Comparative Example 3-2 were subjected to a charge and discharge cycle test at a normal temperature at a voltage of 1.4 V to 2.1 V at a rate of 1 C.
  • Table 4 shows the capacity retention ratio with respect to the first discharge capacity when the batteries C1-C4 and E1 were cycled 100 times, 200 times, and 300 times, respectively, at 1C.
  • the batteries in Examples 3-5 to 3-8 and Comparative Example 3-2 were charged at a constant current of 0.2 C at room temperature, and then charged to 2.0 V, and then the battery was floated at 60 ° C for 2.0 h at 168 h (one week). Test the float current and float capacity of the battery.
  • Table 5 shows the float charge flow and float charge capacity of the batteries C1-C4 and E1 floated at 60 ° C for 168 h.
  • the composite cathode materials of Examples 3-4 were used in Examples 3-9, and the remaining structures and preparation methods of the cathodes were the same as those in Examples 3-5.
  • the negative electrode includes a 50 ⁇ m thick negative electrode active material zinc foil, and the surface of the zinc foil has a lead plating layer, and the mass ratio of the lead plating layer to the zinc foil is 700 ppm.
  • the AGM film serves as a separator.
  • a certain amount of zinc sulfate and lithium sulfate were weighed and dissolved in water to prepare an electrolyte having a zinc sulfate concentration of 2 mol/L and a lithium sulfate concentration of 1 mol/L.
  • the positive electrode, the negative electrode, and the separator were assembled into a battery cell, placed in a casing, and then an electrolyte was injected, sealed, and assembled into a battery having a capacity of 7 mAh, which was designated as C5.
  • the surface of the negative electrode zinc foil had a lead-plated layer, and the mass ratio of the quality of the lead-plated layer to the zinc foil was 300 ppm.
  • the rest of the battery was constructed and prepared in the same manner as in Examples 3-9, and assembled into a battery having a capacity of 7 mAh, which was designated as C6.
  • Example 3-11 the surface of the negative electrode zinc foil had a lead-plated layer, and the mass ratio of the quality of the lead-plated layer to the zinc foil was 100 ppm.
  • the remaining composition and preparation method of the battery were the same as those in Examples 3-9, and assembled into a battery having a capacity of 7 mAh, which was designated as C7.
  • Example 3-12 lead sulfate was added to the electrolytic solution, and the concentration of lead sulfate was 150 ppm.
  • the rest of the battery was constructed and prepared in the same manner as in Examples 3-9, and assembled into a battery having a capacity of 7 mAh, which was designated as C8.
  • the positive electrode active material is lithium manganate LiMn 2 O 4
  • the coating layer is lead
  • the composite positive electrode material is lead oxide-coated lithium manganate, wherein lead in lead monoxide.
  • the mass percentage with lithium manganate was 0.1%.
  • Raw material Lead oxide and lithium manganate were weighed according to a mass ratio of 0.1:100, and mixed in deionized water and stirred. The coating material is uniformly coated on the surface of the positive electrode active material lithium manganate particles, and the uniformly mixed product is dried, and the dried solid material is sintered at 400-650 ° C for 15-30 hours.
  • the positive electrode slurry was coated on a positive electrode current collector graphite foil to form an active material layer, and the surface density of the positive electrode active material was 20 mg/cm 2 .
  • the negative electrode included a 50 ⁇ m thick negative electrode active material zinc foil and a 20 ⁇ m thick negative electrode current collector brass foil.
  • the AGM film serves as a separator.
  • a certain amount of zinc sulfate and lithium sulfate were weighed and dissolved in water to prepare an electrolyte having a zinc sulfate concentration of 2 mol/L and a lithium sulfate concentration of 1 mol/L.
  • the positive electrode, the negative electrode and the separator were assembled into a battery cell, placed in a casing, and then an electrolyte was injected, sealed, and assembled into a battery having a capacity of 7 mAh, which was designated as C9.
  • the batteries C5-C9 of Examples 3-9 to 3-13 were subjected to a charge and discharge cycle test at a normal temperature at a voltage of 1.4 V to 2.1 V at a rate of 1 C.
  • the battery C5-C8 has a capacity retention rate higher than that of the battery C4 100 times. This result indicates that when a lead-containing substance is present on the surface of the negative electrode active material or in the electrolytic solution, dendrites of the negative electrode active material are effectively suppressed, and the cycle performance of the battery is further improved.
  • the capacity retention rate of the battery C9 cycle 100 times is slightly lower than the capacity retention rate of the battery C4. It is higher than the capacity retention rate of the battery E1. This result indicates that the positive electrode of the battery is made of lithium manganese oxide coated with a composite positive electrode material, and the cycle performance of the battery is also improved.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Composite Materials (AREA)
  • Inorganic Chemistry (AREA)
  • Power Engineering (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Secondary Cells (AREA)

Abstract

本发明提供了一种电池,包括正极、负极及电解液,所述正极包括正极活性物质和正极集流体;所述电解液包括第一金属离子和第二金属离子,充放电过程中,所述第一金属离子能够在正极可逆脱出-嵌入,所述第二金属离子在负极能够还原沉积为第二金属且第二金属能可逆氧化溶解为第二金属离子;所述负极包括负极活性物质和负极集流体;所述负极活性物质表面或/和电解液中有含铅物质,且所述含铅物质中的铅与所述电池的质量比不大于1000ppm。本发明能够有效改善电池负极的枝晶问题,增加电池的循环寿命,提高电池的电化学性能和安全性。

Description

电池、电池组和不间断电源 技术领域
本发明属于电池领域,具体涉及一种电池。
本发明还涉及一种电池组,电池组包括若干个电池。
本发明还涉及一种不间断电源。
背景技术
铅酸电池,其出现已超百年,拥有着成熟的电池技术,占据着汽车启动电瓶、电动自行车、UPS等储能领域的绝对市场份额。铅酸电池虽然循环使用寿命较低,能量密度也相对较低,但却拥有价格非常低廉,性价比非常高的优点。因此,近些年来,镍氢电池、锂离子电池、钠硫电池、液流电池等,均无法在储能领域取代铅酸电池。
近几年来出现一种新型水系二次电池。该二次电池的正极能够基于第一金属离子进行可逆的脱出-嵌入反应,负极能够基于第二金属离子进行可逆的还原沉积-氧化溶解反应,电解液含有参与正极脱出-嵌入反应的第一金属离子和参与负极沉积-溶解反应的第二金属离子。该类型电池的电解液为水溶液,不存在类似锂离子电池中有机电解液的安全隐患,且对环境友好,成本较低,能量密度高。因此,该类型电池非常有希望成为替代铅酸电池的下一代储能电池,具有极大的应用价值。
该类型电池的第二金属离子可以为锌离子,此时负极活性物质为金属锌,然而这类负极活性物质在水溶液中充放电时存在枝晶等问题,从而使电池的循环性能、充放电容量受到影响。因此,现有技术需要进一步改善。
发明内容
本发明所要解决的技术问题是提供一种电池,能够改善负极枝晶问题,有效改善电池的循环寿命,提高电池电化学性能。
为实现上述目的,本发明所采用的技术方案如下:一种电池,包括正极、负极及电解液,所述正极包括正极活性物质和正极集流体; 所述电解液包括第一金属离子和第二金属离子,充放电过程中,所述第一金属离子能够在正极可逆脱出-嵌入,所述第二金属离子在负极能够还原沉积为第二金属且第二金属能可逆氧化溶解为第二金属离子;所述负极包括负极活性物质和负极集流体;所述负极活性物质表面或/和电解液中有含铅物质,且所述含铅物质中的铅与所述电池的质量比不大于1000ppm。
优选的,所述负极活性物质表面中含铅物质包括铅金属。
优选的,所述电解液中含铅物质包括铅离子。
优选的,所述电解液中含铅物质中的铅与电解液的质量比不小于10ppm。
优选的,所述含铅物质包括金属铅、硫酸铅和氧化铅中的至少一种。
优选的,所述电池包括添加剂铋化合物,所述铋化合物添加在所述负极和/或所述电解液中。
优选的,所述铋化合物选自三氧化二铋和/或硝酸铋。
优选的,所述铋化合物占电解液总重量的0.01-5%。
优选的,所述铋化合物占负极总重量的0.1-10%。
优选的,所述负极活性物质包括锌。
优选的,所述负极集流体包括黄铜箔。
优选的,所述正极集流体包括尼龙网载体和包覆在所述尼龙网载体上的石墨箔。
优选的,所述第一金属离子包括锂离子、钠离子或镁离子。
优选的,所述第二金属离子包括锌离子。
优选的,所述电解液为水系电解液。
优选的,所述正极活性物质包括锰酸锂改性材料,所述锰酸锂改性材料符合通式Li1+xMnyMzOk,其中,M选自Pb,-1≤x≤0.5,1≤y≤2.5,0<z≤0.1,3≤k≤6。
优选的,所述锰酸锂改性材料表面还包覆有金属铅和/或氧化铅。
优选的,所述正极活性物质表面具有包覆层,所述包覆层为金属铅和/或氧化铅。
优选的,所述金属铅和/或氧化铅中的铅与所述正极活性物质的质量百分比范围为0.001%-10%。
本发明还提供了一种电池组,包括若干个如上所述的电池。
本发明还提供了一种不间断电源,包括如上所述的电池。
与现有技术相比,本发明的有益效果是:通过在负极活性物质表面或/和电解液中添加含铅物质,减缓负极活性物质枝晶问题,从而增加电池的循环寿命,提高电池的电化学性能和安全性能。
本发明所要解决的技术问题是提供一种锰酸锂改性材料,该材料化学稳定性好,容量高,能够很好的与水系电解液搭配,抑制副反应的反应速率,从而提高该材料的电化学性能。
为实现上述目的,本发明所采用的技术方案如下:一种锰酸锂改性材料,所述锰酸锂改性材料符合通式Li1+xMnyMzOk,其中,M选自Pb,-1≤x≤0.5,1≤y≤2.5,0<z≤0.1,3≤k≤6。
优选的,所述锰酸锂改性材料具有尖晶石结构。
优选的,所述锰酸锂改性材料的中值粒径范围为5-20μm,所述锰酸锂改性材料的比表面积范围为0.1-1.0m2/g。
优选的,所述锰酸锂改性材料表面还包覆有金属铅和/或氧化铅。
优选的,所述金属铅和/或氧化铅中的铅与所述锰酸锂改性材料的质量百分比范围为0.001%-10%。
优选的,所述金属铅和/或氧化铅中的铅与所述锰酸锂改性材料的质量百分比范围为0.1%-5%。
本发明还提供了一种电池,能够有效的抑制正极副反应速率,从而进一步改善电池的自放电问题。
为解决上述技术问题,本发明提供的技术方案为:一种电池,包括正极、负极和电解液,所述正极包括正极活性物质和正极集流体,所述电解液为水溶液,所述正极活性物质包括如上所述的锰酸锂改性材料。
优选的,所述电解液包括第一金属离子和第二金属离子,充放电过程中,所述第一金属离子能够在所述正极可逆脱出-嵌入,所述第二金属离子在所述负极能够还原沉积为第二金属且第二金属能可逆氧化溶解为第二金属离子,所述第一金属离子为锂离子。
优选的,所述第二金属离子为锌离子。
优选的,所述负极包括负极活性物质和负极集流体,所述负极活性物质表面或/和电解液中有含铅物质,且所述含铅物质中的铅与所述电池的质量比不大于1000ppm。
优选的,所述电解液的pH值范围为2-8。
本发明还提供了一种电池组,包括若干个电池,所述电池如上所述。
本发明还提供了一种如上所述的锰酸锂改性材料的制备方法,其特征在于,包括以下步骤:
将锂源、锰源和铅源按照一定的比例混合,将混合后的产物进行热处理,热处理的温度为700-850℃,热处理的时间为15-30小时。
与现有技术相比,本发明的有益效果是:通过对锰酸锂掺杂铅进行改性,使得改性后的材料在水系电解液中稳定性能好,从而抑制材料与电解液界面处的副反应发生,使锰酸锂改性材料具有优异的容量和循环性能。采用这种锰酸锂改性的电池的自放电降低、电池浮充性能和循环性能得到明显改善。
本发明所要解决的技术问题是提供一种复合正极材料,该材料化学稳定性好,容量高,能够很好的与水系电解液搭配,抑制副反应的反应速率,从而提高该材料的电化学性能。
为实现上述目的,本发明所采用的技术方案如下:一种复合正极材料,所述复合正极材料包括正极活性物质和包覆层,所述正极活性物质包括锂离子脱嵌化合物,所述包覆层为金属铅、一氧化铅或四氧化三铅中的至少一种。
优选的,所述锂离子脱嵌化合物包括钴酸锂、镍酸锂和锰酸锂、中的至少一种。
优选的,所述复合正极材料的中值粒径范围为5-20μm,所述复合正极材料的比表面积范围为0.1-1.0m2/g。
优选的,所述金属铅、一氧化铅或四氧化三铅中的铅与所述正极活性物质的质量百分比范围为0.001%-10%。
优选的,所述金属铅、一氧化铅或四氧化三铅中的铅与所述正极活性物质的质量百分比范围为0.1%-5%。
本发明还提供了一种电池,能够有效的抑制正极副反应速率,从而进一步改善电池的自放电问题。
为解决上述技术问题,本发明提供的技术方案为:一种电池,包括正极、负极和电解液,所述正极包括复合正极材料和正极集流体,所述电解液为水溶液,所述复合正极材料包括正极活性物质和包覆层,所述正极活性物质包括锂离子脱嵌化合物,所述包覆层为金属铅和/或氧化铅。
优选的,所述电解液包括第一金属离子和第二金属离子,充放电过程中,所述第一金属离子能够在所述正极可逆脱出-嵌入,所述第二金属离子在所述负极能够还原沉积为第二金属且第二金属能可逆氧化溶解为第二金属离子,所述第一金属离子为锂离子。
优选的,所述第二金属离子为锌离子。
优选的,所述负极包括负极活性物质和负极集流体,所述负极活性物质表面或/和电解液中有含铅物质,且所述含铅物质中的铅与所述电池的质量比不大于1000ppm。
优选的,所述金属铅和/或氧化铅中的铅与所述正极活性物质的质量百分比范围为0.001%-10%。
优选的,所述电解液的pH值范围为2-8。
本发明还提供了一种电池组,包括若干个电池,所述电池如上所述。
与现有技术相比,本发明的有益效果是:通过对锂离子脱嵌化合物进行包覆,获得的复合正极材料在水系电解液中稳定性能好,从而抑制材料与电解液界面处的副反应发生,使复合正极材料具有优异的容量和循环性能。采用这种复合正极材料的电池的自放电降低、电池浮充性能和循环性能得到明显改善。
附图说明
图1为实施例1-1及对比例1-1中电池的放电容量、电池内阻与循环次数的关系曲线;
图2为实施例1-5及对比例1-3中三电极体系电池的工作电极的绝对电流密度与时间的曲线;
图3为实施例1-5中三电极体系电池工作1小时后的工作电极的 扫描电镜(SEM)图;
图4为实施例1-6中三电极体系电池工作1小时后的工作电极的扫描电镜(SEM)图;
图5为实施例1-7中三电极体系电池工作1小时后的工作电极的扫描电镜(SEM)图;
图6为对比例1-3中三电极体系电池工作1小时后的工作电极的扫描电镜(SEM)图。
具体实施方式
为了使本发明所解决的技术问题、技术方案及有益效果更加清楚明白,以下结合实施例,对本发明进行进一步详细说明。应当理解,此处所描述的具体实施例仅仅用以解释本发明,并不用于限定本发明。
实施方式一
本发明揭示了一种锰酸锂改性材料,锰酸锂改性材料符合通式Li1+xMnyMzOk,其中,M选自Pb,-1≤x≤0.5,1≤y≤2.5,0<z≤0.1,3≤k≤6。
优选的,掺杂铅后的锰酸锂改性材料仍保持有掺杂前的尖晶石结构,使得锰酸锂改性材料具有很好的结构稳定性。
更优选的,掺杂铅后的锰酸锂改性材料表面还包覆有金属铅和/或氧化铅。示例的,氧化铅包括一氧化铅、二氧化铅和四氧化三铅中的至少一种。利用金属铅和/或氧化铅对锰酸锂改性材料进行包覆使得包覆层在隔绝锰酸锂改性材料与水系电解液的同时使锂离子可自由通过,从而在保证电池正常充放电的同时避免正极与水系电解液界面处的副反应发生,减少正极自放电。
优选的,金属铅和/或氧化铅中的铅与锰酸锂改性材料的质量百分比范围为0.001%-10%。更加优选的,金属铅和/或氧化铅中的铅与锰酸锂改性材料的质量百分比范围为0.1%-5%。这样,既可以保证锰酸锂改性材料得到很好的保护,又不会影响正极的能量密度。
优选的,锰酸锂改性材料的中值粒径D50为5-20μm。
材料的粒径越小,则材料的振实密度小,压实密度小,所得到的电池的体积能量密度较小;而且,粒径较小,材料加工性能差,配浆 料过程中易于发生团聚等现象,不易涂布。材料的粒径越大,充放电过程中,锂离子脱嵌的路径较长,材料的导电性能差,倍率性能不好。所以本发明将锰酸锂改性材料的中值粒径为5-20μm,以避免上述问题。示例的,中值粒径D50可以为5-10μm、5-15μm、8μm、12μm、16μm、18μm等。
优选的,锰酸锂改性材料的比表面积为0.1-1.0m2/g。
材料比表面积太大,材料表面能高,配浆料易发生团聚,材料与电解液接触面大,将增加副反应。所以为了避免上述问题的出现,提高锰酸锂改性材料的加工性能,本发明中锰酸锂改性材料的比表面积范围为0.1-1.0m2/g。
本发明具体实施例中还提供了一种锰酸锂改性材料的制备方法,具体,制备方法包括以下步骤:
将锂源、锰源和铅源按照一定的比例混合,将混合后的产物进行热处理,热处理的温度为700-850℃,热处理的时间为15-30小时。
具体的,按照通式Li1+xMnyMzOk的化学计量比,称取锂源、锰源和M源。
在通式Li1+xMnyMzOk中,M选自Pb,-1≤x≤0.5,1≤y≤2.5,0<z≤0.1,3≤k≤6。
将称取的锂源、锰源和铅源混合,混合包括湿混和干混。在具体的实施例中,将称取的锂源、锰源和铅源在酒精中混合,混合后搅拌均匀。
将搅拌均匀后的产物进行热处理,具体的,在含氧气氛中进行热处理,热处理条件为以1~10℃/min的升温速度加热到700-850℃,热处理15-30小时。最后自然降温至室温,得到铅掺杂的锰酸锂改性材料。
具体的,锂源包括但不仅限于碳酸锂,锰源包括但不仅限于四氧化三锰,铅源包括但不仅限于硫酸铅和氧化铅。
本发明提供的锰酸锂改性材料,通过对锰酸锂掺杂铅进行改性,使得改性后的材料在水系电解液中稳定性能好,从而抑制材料与电解液界面处的副反应发生,使锰酸锂改性材料具有优异的容量和循环性能。采用这种锰酸锂改性的电池的自放电降低、电池浮充性能和循环 性能得到明显改善。
实施方式二
本发明揭示了一种复合正极材料,复合正极材料包括正极活性物质和包覆层,正极活性物质包括锂离子脱嵌化合物,包覆层为金属铅、一氧化铅或四氧化三铅中的至少一种。
正极活性物质锂离子脱嵌化合物表面包覆有铅、一氧化铅或四氧化三铅中的至少一种。利用铅、一氧化铅或四氧化三铅中的至少一种对锂离子脱嵌化合物进行包覆使得包覆层在减少正极活性物质与水系电解液的同时使锂离子可自由通过,从而在保证电池正常充放电的同时避免正极活性物质与水系电解液界面处的副反应发生,从而减少正极自放电。
具体的,锂离子脱嵌化合物包括钴酸锂、镍酸锂和锰酸锂中的至少一种。
优选的,金属铅、一氧化铅或四氧化三铅中的铅与正极活性物质的质量百分比范围为0.001%-10%。具体的,当包覆层仅为单一组分,如金属铅、一氧化铅或四氧化三铅时,那么金属铅、一氧化铅中的铅或四氧化三铅中的铅与正极活性物质的质量百分比范围为0.001-10%。当包覆层为混合组分时,如金属铅和一氧化铅,那么金属铅和一氧化铅中的铅总共与正极活性物质的质量百分比范围为0.001-10%。
更加优选的,金属铅、一氧化铅或四氧化三铅中的铅与正极活性物质的质量百分比范围为0.1%-5%。这样,既可以保证锰酸锂改性材料得到很好的保护,又不会影响正极的能量密度。
优选的,复合正极材料的中值粒径D50为5-20μm。
材料的粒径越小,则材料的振实密度小,压实密度小,所得到的电池的体积能量密度较小;而且,粒径较小,材料加工性能差,配浆料过程中易于发生团聚等现象,不易涂布。材料的粒径越大,充放电过程中,锂离子脱嵌的路径较长,材料的导电性能差,倍率性能不好。所以本发明将复合正极材料的中值粒径为5-20μm,以避免上述问题。示例的,中值粒径D50可以为5-10μm、5-15μm、12μm、14μm、16μm、18μm等。
优选的,复合正极材料的比表面积为0.1-1.0m2/g。
材料比表面积太大,材料表面能高,配浆料易发生团聚,材料与电解液接触面大,将增加副反应。所以为了避免上述问题的出现,提高复合正极材料的加工性能,本发明中复合正极材料的比表面积范围为0.1-1.0m2/g。
本发明具体实施例中还提供了一种复合正极材料的制备方法,具体的,制备方法包括以下步骤:
按照预定重量比称取正极活性物质锂离子脱嵌化合物和铅源。
将称取的锂离子脱嵌化合物和铅源混合,搅拌均匀,使包覆材料铅源均匀包覆在锂离子脱嵌化合物上。混合包括干混和湿混。湿混时采用的溶剂包括但不仅限于酒精。
将混合后的产物进行烧结。当然烧结前可以对混合后的产物进行干燥。具体的,烧结条件为以1~10℃/min的升温速度加热到400-650℃,保温15-30小时。最后自然降温至室温,得到复合正极材料。
具体的,铅源包括但不仅限于醋酸铅、一氧化铅和四氧化三铅。
本发明提供的复合正极材料,通过对锂离子脱嵌化合物进行包覆,使得包覆后的材料在水系电解液中稳定性能好,从而抑制材料与电解液界面处的副反应发生,使锂离子脱嵌化合物具有优异的容量和循环性能。采用这种复合正极材料的电池的自放电降低、电池浮充性能和循环性能得到明显改善。
实施方式三
本发明揭示了一种电池,包括正极、负极及电解液,正极包括正极活性物质和正极集流体;电解液包括第一金属离子和第二金属离子,充放电过程中,第一金属离子能够在正极可逆脱出-嵌入,第二金属离子在负极能够还原沉积为第二金属且第二金属能可逆氧化溶解为第二金属离子;负极包括负极活性物质和负极集流体;负极活性物质表面或/和电解液中有含铅物质,且所述含铅物质中的铅与所述电池的质量比不大于1000ppm。
本发明电池的充放电原理为:充电时,正极活性物质脱出第一金属离子,同时伴随正极活性物质被氧化,并放出电子;电子经由外电 路到达电池负极活性物质,同时电解液中的第二金属离子在负极活性物质上得到电子被还原,并沉积在负极活性物质上。放电时,负极活性物质的第二金属被氧化,失去电子转变为第二金属离子进入电解液中;电子经外电路到达正极,正极活性物质接受电子被还原,同时第一金属离子嵌入正极活性物质中。
电池的正极包括正极活性物质,正极活性物质参与正极反应,并且能够可逆脱出-嵌入第一金属离子。
正极活性物质有多种选择。
选择一
正极活性物质可以是符合通式Li1+xMnyMzOk的能够可逆脱出-嵌入锂离子的尖晶石结构的化合物,其中,-1≤x≤0.5,1≤y≤2.5,0≤z≤0.5,3≤k≤6,M选自Na、Li、Co、Mg、Ti、Cr、V、Zn、Zr、Si、Al中的至少一种。优选的,正极活性物质含有LiMn2O4
正极活性物质可以是符合通式Li1+xMyM′zM″cO2+n的能够可逆脱出-嵌入锂离子的层状结构的化合物,其中,-1<x≤0.5,0≤y≤1,0≤z≤1,0≤c≤1,-0.2≤n≤0.2,M,M′,M″分别选自Ni、Mn、Co、Mg、Ti、Cr、V、Zn、Zr、Si或Al的中至少一种。优选的,正极活性物质含有LiCoO2
正极活性物质还可以是符合通式LixM1-yM′y(XO4)n的能够可逆脱出-嵌入锂离子的橄榄石结构的化合物,其中,0<x≤2,0≤y≤0.6,1≤n≤1.5,M选自Fe、Mn、V或Co,M′选自Mg、Ti、Cr、V或Al的中至少一种,X选自S、P或Si中的至少一种。优选的,正极活性物质含有LiFePO4
目前电池工业中,几乎所有正极活性物质都会经过掺杂、包覆等改性处理。但掺杂,包覆改性等手段造成材料的化学通式表达复杂,如LiMn2O4已经不能够代表目前广泛使用的“锰酸锂”的通式,而应该以通式Li1+xMnyMzOk为准,广泛地包括经过各种改性的LiMn2O4正极活性物质。同样的,LiFePO4以及LiCoO2也应该广泛地理解为包括经过各种掺杂、包覆等改性的,通式分别符合LixM1-yM′y(XO4)n和Li1+xMyM′zM″cO2+n的正极活性物质。
正极活性物质为能可逆脱出-嵌入锂离子的物质时,优选可以选 用如LiMn2O4、LiFePO4、LiCoO2、LiMxPO4、LiMxSiOy(其中M为一种变价金属)等化合物。
更优选的,正极活性物质为LiMn2O4。在众多正极材料中,LiMn2O4被认为是最具有前景的正极材料之一,因为它具有成本低、原料充足、环境友好、安全性好等优点。
此外,可脱出-嵌入钠离子的化合物(如NaVPO4F),可脱出-嵌入镁离子的化合物(如MgMxOy(其中M为一种金属,0.5<x<3,2<y<6))以及具有类似功能,能够脱出-嵌入离子或官能团的化合物都可以作为本发明电池的正极活性物质。
选择二
优选的,正极活性物质包括锰酸锂改性材料,此时,第一金属离子为锂离子。
锰酸锂改性材料符合通式Li1+xMnyMzOk,其中,M选自Pb,-1≤x≤0.5,1≤y≤2.5,0<z≤0.1,3≤k≤6。锰酸锂改性材料在实施方式一中已详细介绍,这里就不再赘述。
选择三
优选的,正极活性物质表面具有包覆层,正极活性物质包括锂离子脱嵌化合物,包覆层为金属铅和/或氧化铅。
具体的,锂离子脱嵌化合物包括钴酸锂、镍酸锂和锰酸锂中的至少一种。
优选的,金属铅和/或氧化铅中的铅与正极活性物质的质量百分比范围为0.001%-10%。更加优选的,金属铅和/或氧化铅中的铅与正极活性物质的质量百分比范围为0.1%-5%。这样,既可以保证正极活性物质得到很好的保护,又不会影响正极的能量密度。
示例的,氧化铅包括一氧化铅、二氧化铅或四氧化三铅。
正极活性物质表面具有包覆层后的中值粒径、比表面积以及制备方法同实施方式二中复合正极材料,这里就不再一一赘述。
具体的,在制备正极材料时,除了正极活性物质之外,通常还会添加正极导电剂和正极粘结剂来提升正极的性能。
导电剂能降低整体正极的电阻,同时加强正极材料颗粒之间的导 电通路。正极导电剂选自导电聚合物、导电氧化物、导电陶瓷、活性碳、石墨烯、碳黑、石墨、碳纤维、金属纤维、金属粉末、以及金属薄片中的一种或多种。优选的,正极导电剂占正极材料的质量百分比为1%-15%。更进一步的,正极导电剂为石墨,正极导电剂占正极材料的质量百分比为10%-14%。
粘结剂有利于使正极活性物质和导电剂均匀的粘结在一起,从而加工形成正极。正极粘结剂可以选自聚乙烯氧化物、聚丙烯氧化物,聚丙烯腈、聚酰亚胺、聚酯、聚醚、氟化聚合物、聚二乙烯基聚乙二醇、聚乙二醇二丙烯酸酯、聚乙二醇二甲基丙烯酸中的一种、或上述聚合物的混合物及衍生物。更优选的,正极粘结剂选自聚四氟乙烯(PTFE)、聚偏氟乙烯(PVDF)或丁苯橡胶(SBR)。
具体的,正极还包括负载正极活性物质的正极集流体,正极集流体仅作为电子传导和收集的载体,不参与电化学反应,即在电池工作电压范围内,正极集流体能够稳定的存在于电解液中而基本不发生副反应,从而保证电池具有稳定的循环性能。
正极集流体的材料选自碳基材料、金属或合金中的一种。
碳基材料选自玻璃碳、石墨箔、石墨片、泡沫碳、碳毡、碳布、碳纤维中的一种。
优选的,正极集流体包括载体和包覆在载体上的石墨箔。
本发明中,将石墨箔作为正极集流体使用,不仅减轻了正极的重量,而且在水系电解液中石墨箔稳定性好,使电池具有更高的浮充寿命,同时降低了电池成本,使电池具备了商业化应用的前景。
载体本身电化学惰性,主要起到承载石墨箔的作用,从而提高石墨箔的机械性能。载体的材料选自聚对苯二甲酸乙二酯、聚对苯二甲酸丁二酯、聚乙烯、聚丙烯、聚酰胺、聚氨基甲酸酯、聚丙烯腈中的一种。这些聚合物材料可以稳定的存在于正极集流体中而不参与电化学反应,为电池较高的能量密度输出节省重量。优选的,载体为尼龙网,即聚酰胺。
金属包括Ni、Al、Fe、Cu、Pb、Ti、Cr、Mo、Co、Ag或经过钝化处理的上述金属中的一种。
合金包括不锈钢、碳钢、Al合金、Ni合金、Ti合金、Cu合金、Co合金、Ti-Pt合金、Pt-Rh合金或经过钝化处理的上述金属中的一种。
不锈钢包括不锈钢网、不锈钢箔,不锈钢的型号包括但不仅限于不锈钢304或者不锈钢316或者不锈钢316L中的一种。
优选的,对正极集流体进行钝化处理,其主要目的是,使正极集流体的表面形成一层钝化的氧化膜,从而在电池充放电过程中,能起到稳定的收集和传导电子的作用,而不会参与电池反应,保证电池性能稳定。正极集流体钝化处理方法包括化学钝化处理或电化学钝化处理。
化学钝化处理包括通过氧化剂氧化正极集流体,使正极集流体表面形成钝化膜。氧化剂选择的原则为氧化剂能使正极集流体表面形成一层钝化膜而不会溶解正极集流体。氧化剂选自但不仅限于浓硝酸或硫酸高铈(Ce(SO4)2)。
电化学钝化处理包括对正极集流体进行电化学氧化或对含有正极集流体的电池进行充放电处理,使正极集流体表面形成钝化膜。
优选的,正极还包括负载正极活性物质的复合集流体,复合集流体包括正极集流体和包覆在正极集流体上的导电膜。
导电膜满足在水系电解液中可以稳定存在、不溶于电解液、不发生溶胀、高电压不能被氧化、易于加工成致密、不透水并且导电的要求。一方面,导电膜对正极集流体可以起到保护作用,避免水系电解液对正极集流体的腐蚀。另一方面,有利于降低正极片与正极集流体之间的接触内阻,提高电池的能量。优选的,导电膜的厚度为10μm~2mm。
正极集流体具有相对设置的第一面和第二面,优选的,正极集流体的第一面和第二面均包覆有导电膜。
导电膜包含作为必要组分的聚合物,聚合物占导电膜的重量比重为50~95%,优选的,聚合物选自热塑性聚合物。为了使导电膜能够导电,有两种可行的形式:(1)聚合物为导电聚合物;(2)除了聚合物之外,导电膜还包含导电填料。
导电聚合物选材要求为具有导电能力但电化学惰性,即不会作为电荷转移介质的离子导电。具体的,导电聚合物包括但不仅限于聚乙炔、聚吡咯、聚噻吩、聚苯硫醚、聚苯胺、聚丙烯腈、聚喹啉、聚对苯撑(polyparaphenylene)及其任意混合物。导电聚合物本身就具有导电性,但还可以对导电聚合物进行掺杂或改性以进一步提高其导电能力。从导电性能和电池中的稳定使用考量,导电聚合物优选聚苯胺、聚吡咯、聚噻吩和聚乙炔。
同样的,导电填料的选材要求为表面积小、难于氧化、结晶度高、具有导电性但电化学惰性,即不会作为电荷转移介质的离子导电。
导电填料的材料包括但不仅限于导电聚合物、碳基材料或金属氧化物。导电填料在导电膜中的质量百分比范围为5~50%。导电填料的平均粒径并没有特别限定,通常范围在100nm~100μm。
当导电膜中包含导电填料时,导电膜中的聚合物优选包含起到结合导电填料作用的非导电聚合物,非导电聚合物增强了导电填料的结合,改善了电池的可靠性。优选的,非导电聚合物为热塑性聚合物。
具体的,热塑性聚合物包括但不仅限于聚烯烃如聚乙烯、聚丙烯,聚丁烯,聚氯乙烯,聚苯乙烯,聚酰胺,聚碳酸酯,聚甲基丙烯酸甲酯,聚甲醛,聚苯醚,聚砜,聚醚砜、丁苯橡胶或聚偏氟乙烯中的一种或多种。其中,优选为聚烯烃、聚酰胺和聚偏氟乙烯。这些聚合物容易通过热而熔化,因此容易与正极集流体复合在一起。此外,这些聚合物具有大电位窗口,从而使正极稳定并为电池输出密度节省重量。
优选的,导电膜通过热压复合、抽真空或喷涂的方式结合到正极集流体上。
电解液包括电解质以及溶剂。其中,电解液中溶剂的目的是溶解电解质,并使电解质在溶剂中电离,最终在电解液中生成可自由移动的阳离子和阴离子。本发明中电解液优选为水系电解液,则溶剂优选为水。
电解液中所包括的第一金属离子在充放电过程中在正极能够可逆脱出-嵌入。即在电池充电时,第一金属离子从正极活性物质中脱 出,进入电解液;在电池放电时,电解液中的第一金属离子嵌入正极活性物质中。
优选的,第一金属离子选自锂离子、钠离子或镁离子。更优选的,第一金属离子为锂离子。
优选的,电解液还包括第二金属离子,第二金属离子在充电过程中在负极还原沉积为第二金属,在放电过程中第二金属氧化溶解为第二金属离子。优选的,第二金属离子为锌离子。
优选的,第一金属离子不同于第二金属离子。在一优选实施方式下,电解液中包括锂离子和锌离子。在充放电过程中,锂离子在正极发生嵌入-脱出,锌离子在负极发生沉积-溶解。
电解液中的阴离子,可以是任何基本不影响正负极反应、以及电解质在溶剂中溶解的阴离子。例如可以是硫酸根离子、氯离子、醋酸根离子、硝酸根离子、磷酸根离子、甲酸根离子、烷基磺酸根离子及其混合等。
电解液中各离子的浓度,可以根据不同电解质、溶剂、以及电池的应用领域等不同情况而进行改变调配。
优选的,在电解液中,第一金属离子的浓度为0.1~10mol/L。
优选的,在电解液中,第二金属离子的浓度为0.5~15mol/L。
优选的,在电解液中,阴离子的浓度为0.5~12mol/L。
为了使电池性能更加优化,电解液的pH值范围为3~7。pH的范围可以通过缓冲剂来调剂。电解液的pH过高,可能会影响电解液中锌离子的浓度,电解液的pH过低,则会加剧电极材料的腐蚀。而将电解液的pH范围保持在3~7,既可以有效保证电解液中金属离子的浓度,还可以避免电极腐蚀。
电池的负极包括负极活性物质,负极活性物质能够发生可逆的还原沉积-氧化溶解反应。充电时,第二金属离子能够在负极活性物质侧被还原为第二金属,并沉积在负极活性物质上。放电时,负极活性物质上的第二金属被重新氧化成第二金属离子进入电解液中。优选的,第二金属离子为锌离子。此时,电池的负极根据结构以及作用的不同,可以分为以下两种不同的形式:
在第一优选的实施例中,负极包括负极集流体和负载在负极集流 体上的负极活性物质。
负极集流体作为电子传导和收集的载体,不参与电化学反应。负极集流体的材料选自金属Ni、Cu、Ag、Pb、Mn、Sn、Fe、Al或经过钝化处理的上述金属中的至少一种,或者单质硅,或者碳基材料;其中,碳基材料包括石墨材料,比如商业化的石墨压制的箔,其中石墨所占的重量比例范围为90~100%。负极集流体的材料还可以选自不锈钢或经钝化处理的不锈钢。不锈钢包括但不仅限于不锈钢网和不锈钢箔,同样的,不锈钢的型号可以是300系列的不锈钢,如不锈钢304或者不锈钢316或者不锈钢316L。
优选的,负极集流体为黄铜箔。
负极活性物质以片状或者粉末状存在。
当采用片状的负极活性物质时,负极活性物质与负极集流体形成复合层。
当采用粉末状的负极活性物质时,将负极活性物质粉末制成浆料,然后将浆料涂覆在负极集流体上制成负极。具体的实施方式中,制备负极时,除了负极活性物质粉末之外,根据实际情况,还可以根据需要添加负极导电剂和负极粘结剂来提升负极的性能。
优选的,负极活性物质为锌。
在一优选的实施例下,负极包括黄铜箔和锌箔,黄铜箔作为负极集流体,锌箔作为负极活性物质,可参与负极反应。
在第二优选的实施例中,直接采用负极活性物质作为负极,即负极活性物质同时也作为负极集流体。
不论负极采用上述何种形式,负极活性物质在电池充放电过程中均可能存在枝晶的问题。在本发明中,通过使负极活性物质表面或/和电解液中有含铅物质,来改善负极活性物质枝晶问题。优选的,负极活性物质表面或/和电解液中的含铅物质中的铅的总含量相对于电池的质量比不大于1000ppm。优选的,含铅物质包括金属铅、硫酸铅和氧化铅中的至少一种。
在一优选实施方式下,仅在负极活性物质表面有含铅物质。更优选的,负极活性物质表面中含铅物质包括铅金属。
应该指出的是,本发明中的“负极活性物质表面”是指负极活性物 质与正极相对的一侧界面。“负极活性物质表面有含铅物质”可以有两种理解:当含铅物质(单质或化合物)以粉末状形式加入负极活性物质,则含铅物质的粉末颗粒位于负极活性物质表面的面内;当含铅物质以镀层或涂层方式加入负极活性物质,则含铅物质的镀层或涂层位于负极活性物质表面的面上。
当负极活性物质表面形成有含铅物质,负极活性物质的枝晶能得到有效抑制,电池的循环性能也能得到明显提高。
优选的,负极活性物质表面含铅物质中的铅与负极活性物质的质量比不大于1000ppm。即不论含铅物质为铅金属单质或其化合物中的任意一种或多种,“负极活性物质表面的铅”是指其中所含的铅的总量。
含铅物质加到负极活性物质的方法可以是物理方法或者化学方法,物理方法包括但不限于机械混合、机械涂覆、真空镀到负极活性物质上、或磁控溅射到负极活性物质上;化学方法包括但不限于电化学镀到负极活性物质上等。
在一优选实施方式下,仅在电解液中有含铅物质。更优选的,电解液中的含铅物质包括铅离子。
当电解液中添加有含铅物质时,负极活性物质的枝晶也能得到有效的抑制。含铅物质添加到电解液中,有铅离子进入到电解液中,即使含铅物质一开始难溶于电解液,但在充放电过程中,也会慢慢溶解形成铅离子。电解液中的铅离子会对第二金属离子在负极活性物质表面上的沉积-溶解的动力学过程有促进作用,能稳定第二金属离子的沉积过程,改变第二金属离子在负极活性物质表面的沉积晶面方向,从而使第二金属离子获得均匀的沉积层,同时抑制负极活性物质的枝晶生长。
优选的,电解液中含铅物质中的铅与电解液的质量比不小于10ppm。当添加的含铅物质完全溶解于电解液,“电解液中含铅物质中的铅”是指铅离子;当添加的含铅物质不完全溶于电解液,“电解液中含铅物质中的铅”是指不溶的那部分含铅物质中的铅及溶解于电解液中的铅离子的总量。
含铅物质加入电解液的方法包括但不限于直接加入电解液中,或 者以悬浮液滴加在隔膜上。更优选的,将这些添加剂直接加入到电解液中,然后将电解液滴到隔膜上。
在另一优选实施方式下,负极活性物质表面与电解液中同时有含铅物质。更优选的,负极活性物质表面中的含铅物质包括铅金属同时电解液中的含铅物质包括铅离子。
优选的,电解液中含铅物质中的铅与电解液的质量比不小于10ppm。
优选的,电池还包括添加剂铋化合物,铋化合物添加在负极或电解液或负极和电解液同时添加。
优选的,铋化合物选自三氧化二铋和/或硝酸铋。
铋化合物在负极中的使用剂量优选如下:
当单独使用三氧化二铋时,三氧化二铋占负极总重量的0.1~10%。
当单独使用硝酸铋时,硝酸铋占负极总重量的0.1~10%。
当然也可以使用三氧化二铋和硝酸铋的混合物。
铋化合物在电解液中的使用剂量优选如下:
当单独使用三氧化二铋时,三氧化二铋占电解液总重量的0.01~5%。
当单独使用硝酸铋时,硝酸铋占电解液总重量的0.01~5%。
当然也可以使用三氧化二铋和硝酸铋的混合物。
当然为了使电池性能更加优异,在负极和电解液中同时加入铋化合物。
铋化合物加入负极和/或电解液时,根据负极和电解液形态结构的不同情况,可以选自不同的加入方式,类似于含铅物质的加入方法。
为了提供更好的安全性能,优选在电解液中位于正极与负极之间还设有隔膜。隔膜可以避免其他意外因素造成的正负极相连而造成的短路。
隔膜没有特殊要求,只要是允许电解液通过且电子绝缘的隔膜即可。有机系锂离子电池采用的各种隔膜,均可以适用于本发明。隔膜还可以是微孔陶瓷隔板等其他材料。
本发明还提供了一种电池组,电池组包含若干个上述的电池,具 体的,通过串联、并联或其组合连接两个以上电池来生产电池组。电池组的容量和电压可以通过电池的串联和/或并联方式自由地调整。根据本发明提供的电池或由电池构建的电池组可以用作车辆和运输设备如动力火车的电源,并用作可固定/可安装电源如不间断电源。
实施方式四
本发明还揭示了一种电池,包括正极、负极和电解液,正极包括正极活性物质和正极集流体,正极活性物质包括锰酸锂改性材料。电解液为水溶液。
正极活性物质参与电化学反应,具体的,正极活性物质中的锰酸锂改性材料符合通式Li1+xMnyMzOk,其中,M选自pb,-1≤x≤0.5,1≤y≤2.5,0<z≤0.1,3≤k≤6。具体的,锰酸锂改性材料在实施方式一中已经介绍,这里就不再赘述。
具体的,在制备正极材料时,除了正极活性物质之外,通常还会添加正极导电剂和正极粘结剂来提升正极的性能。正极导电剂和正极粘结剂在实施方式三中已经介绍,这里就不再赘述。
正极活性物质负载在正极集流体上,正极集流体作为电子传导和收集的载体,不参与电化学反应,即在电池工作电压范围内,正极集流体能够稳定的存在于电解液中而基本不发生副反应,从而保证电池具有稳定的循环性能。
正极集流体的选材在实施方式三中已经介绍,这里就不再赘述。
下面,通过一个优选的实施例来进一步介绍实施方式四中的电池。
一种电池,包括正极、负极和电解液,正极包括正极活性物质和正极集流体,正极活性物质包括如前所述的锰酸锂改性材料。电解液为水溶液,电解液还包括第一金属离子和第二金属离子。电池在充放电过程中,第一金属离子能够在正极可逆脱出-嵌入,第二金属离子在负极能够还原沉积为第二金属且第二金属能可逆氧化溶解为第二金属离子,第一金属离子为锂离子。
电池的工作原理为:电池充电时,正极活性物质锰酸锂改性材料中脱出锂离子,并放出电子;电子经由外电路到达电池负极,同时电解液中的第二金属离子在负极上得到电子被还原,并沉积在负极上形 成第二金属;放电时,负极处的第二金属被氧化,失去电子转变为第二金属离子进入电解液中;电子经外电路到达正极,正极活性物质接受电子被还原,同时电解液中的第一金属离子锂离子嵌入到正极活性物质中。
电解液中所包括的第一金属离子锂离子在充放电过程中在正极能够可逆脱出-嵌入。即在电池充电时,第一金属离子锂离子从正极活性物质锰酸锂改性材料中脱出,进入电解液;在电池放电时,电解液中的第一金属离子锂离子嵌入正极活性物质锰酸锂改性材料中。
优选的,第二金属离子为锌离子。
电解液中的阴离子,可以是任何基本不影响正负极反应、以及电解质在溶剂中溶解的阴离子。例如可以是硫酸根离子、氯离子、醋酸根离子、硝酸根离子、磷酸根离子、甲酸根离子、烷基磺酸根离子及其混合等。
电解液中各离子的浓度,可以根据不同电解质、溶剂、以及电池的应用领域等不同情况而进行改变调配。
优选的,在电解液中,第一金属离子锂离子的浓度为0.1~10mol/L。
优选的,在电解液中,第二金属离子的浓度为0.5~15mol/L。
优选的,在电解液中,阴离子的浓度为0.5~12mol/L。
为了使电池性能更加优化,电解液的pH值范围为2~8。pH的范围可以通过缓冲剂来调剂。电解液的pH过高,可能会影响电解液中锌离子的浓度,电解液的pH过低,则会加快电极材料的腐蚀。而将电解液的pH范围保持在2~8,既可以有效保证电解液中金属离子的浓度,还可以避免电极腐蚀。
负极根据其结构以及作用的不同,可以为以下三种不同的形式:
负极仅包括负极集流体,并且负极集流体仅作为电子传导和收集的载体,不参与电化学反应。
示例的,负极集流体为铜箔、不锈钢网、不锈钢箔或石墨箔。
负极仅包括负极活性物质,负极活性物质同时作为负极集流体。示例的,第二金属离子为锌离子,负极为锌箔。锌箔可参与负极反应。
优选的,负极包括负极活性物质和负极集流体,负极活性物质负 载在负极集流体上。负极活性物质与第二金属相同,如电解液中第二金属离子为Zn2+,第二金属为金属Zn,那么负极活性物质对应也为金属Zn。更加优选的,负极包括黄铜箔和锌箔,黄铜箔作为负极集流体,锌箔对应负极活性物质,可参与负极反应。
负极活性物质以片状或者粉末状存在。
当负极活性物质为片状时,负极活性物质与负极集流体形成复合层。
当负极活性物质为粉末时,将第二金属粉末制成浆料,然后将浆料涂覆在负极集流体上制成负极。在具体的实施方式中,制备负极时,除了负极活性物质第二金属粉末之外,根据实际情况,还根据需要添加负极导电剂和负极粘结剂来提升负极的性能。
不论负极采用上述何种形式,负极活性物质在电池充放电过程中均可能存在枝晶的问题。在本发明中,通过使负极活性物质表面或/和电解液中有含铅物质,来改善负极活性物质枝晶问题。
具体在实施方式四中,在负极活性物质表面或/和电解液中有含铅物质同实施方式三,这里就不再赘述。
为了提供更好的安全性能,优选在电解液中位于正极与负极之间还设有隔膜。隔膜可以避免其他意外因素造成的正负极相连而造成的短路。
隔膜没有特殊要求,只要是允许电解液通过且电子绝缘的隔膜即可。有机系锂离子电池采用的各种隔膜,均可以适用于本发明。隔膜还可以是微孔陶瓷隔板等其他材料。
本发明提供的锰酸锂改性材料与水系电解液具有很好的相容性,锰酸锂改性材料和水系电解液界面处的副反应得到抑制。更进一步的,采用锰酸锂改性材料作为正极活性物质的电池,循环、自放电和浮充性能明显得到改善,使得本发明提供的电池具有良好的商业应用前景。
本发明还提供了一种电池组,电池组包含若干个上述的电池,具体的,通过串联、并联或其组合连接两个以上电池来生产电池组。电池组的容量和电压可以通过电池的串联和/或并联方式自由地调整。根据本发明提供的电池或由电池构建的电池组可以用作车辆和运输设 备如动力机车的电源,并用作可固定/可安装电源如不间断电源。
实施方式五
本发明还揭示了一种电池,包括正极、负极和电解液,正极包括复合正极材料和正极集流体,复合正极材料包括正极活性物质和包覆层,正极活性物质包括锂离子脱嵌化合物,包覆层为金属铅和/或氧化铅。电解液为水溶液。
具体的,金属铅和/或氧化铅中的铅与所述正极活性物质的质量百分比范围为0.001%-10%。氧化铅包括一氧化铅、二氧化铅和四氧化三铅中的至少一种。
正极活性物质参与电化学反应。具体的,复合正极材料在实施方式二中已经介绍,这里就不再赘述。
具体的,在制备正极材料时,除了复合正极材料之外,通常还会添加正极导电剂和正极粘结剂来提升正极的性能。正极导电剂和正极粘结剂在实施方式三中已经介绍,这里就不再赘述。
复合正极材料负载在正极集流体上,正极集流体作为电子传导和收集的载体,不参与电化学反应,即在电池工作电压范围内,正极集流体能够稳定的存在于电解液中而基本不发生副反应,从而保证电池具有稳定的循环性能。
正极集流体同实施方式三中正极集流体,这里就不再赘述。
下面,通过一个优选的实施例来进一步介绍实施方式五中的电池。
一种电池,包括正极、负极和电解液,正极包括复合正极材料和正极集流体,复合正极材料如前所述。电解液为水溶液,电解液还包括第一金属离子和第二金属离子。电池在充放电过程中,第一金属离子能够在正极可逆脱出-嵌入,第二金属离子在负极能够还原沉积为第二金属且第二金属能可逆氧化溶解为第二金属离子,第一金属离子为锂离子。
电池的工作原理为:电池充电时,正极活性物质锂离子脱嵌化合物中脱出锂离子,并放出电子;电子经由外电路到达电池负极,同时电解液中的第二金属离子在负极上得到电子被还原,并沉积在负极上形成第二金属;放电时,负极处的第二金属被氧化,失去电子转变为 第二金属离子进入电解液中;电子经外电路到达正极,正极活性物质接受电子被还原,同时电解液中的第一金属离子锂离子嵌入到正极活性物质中。
电解液中所包括的第一金属离子锂离子在充放电过程中在正极能够可逆脱出-嵌入。即在电池充电时,第一金属离子锂离子从正极活性物质锂离子脱嵌化合物中脱出,进入电解液;在电池放电时,电解液中的第一金属离子锂离子嵌入正极活性物质锂离子脱嵌化合物中。
优选的,第二金属离子为锌离子。
电解液中的阴离子,可以是任何基本不影响正负极反应、以及电解质在溶剂中溶解的阴离子。例如可以是硫酸根离子、氯离子、醋酸根离子、硝酸根离子、磷酸根离子、甲酸根离子、烷基磺酸根离子及其混合等。
电解液中各离子的浓度,可以根据不同电解质、溶剂、以及电池的应用领域等不同情况而进行改变调配。
优选的,在电解液中,第一金属离子锂离子的浓度为0.1~10mol/L。
优选的,在电解液中,第二金属离子的浓度为0.5~15mol/L。
优选的,在电解液中,阴离子的浓度为0.5~12mol/L。
为了使电池性能更加优化,电解液的pH值范围为2~8。pH的范围可以通过缓冲剂来调剂。电解液的pH过高,可能会影响电解液中锌离子的浓度,电解液的pH过低,则会加快电极材料的腐蚀。而将电解液的pH范围保持在2~8,既可以有效保证电解液中金属离子的浓度,还可以避免电极腐蚀。
负极同实施方式四中负极,这里就不再赘述。
不论负极采用上述何种形式,负极活性物质在电池充放电过程中均可能存在枝晶的问题。在本发明中,通过使负极活性物质表面或/和电解液中有含铅物质,来改善负极活性物质枝晶问题。
具体在实施方式五中,在负极活性物质表面或/和电解液中有含铅物质同实施方式三,这里就不再赘述。
为了提供更好的安全性能,优选在电解液中位于正极与负极之间 还设有隔膜。隔膜可以避免其他意外因素造成的正负极相连而造成的短路。
隔膜没有特殊要求,只要是允许电解液通过且电子绝缘的隔膜即可。有机系锂离子电池采用的各种隔膜,均可以适用于本发明。隔膜还可以是微孔陶瓷隔板等其他材料。
本发明提供的复合正极材料与水系电解液具有很好的相容性,复合正极材料和水系电解液界面处的副反应得到抑制。更进一步的,采用复合正极材料作为正极活性物质的电池,循环、自放电和浮充性能明显得到改善,使得本发明提供的电池具有良好的商业应用前景。
本发明还提供了一种电池组,电池组包含若干个上述的电池,具体的,通过串联、并联或其组合连接两个以上电池来生产电池组。电池组的容量和电压可以通过电池的串联和/或并联方式自由地调整。根据本发明提供的电池或由电池构建的电池组可以用作车辆和运输手段如火车的电源,并用作可固定/可安装电源如不间断电源。
下面通过实施例对本发明进一步说明。
实施例1-1
制备正极:将锰酸锂LMO、导电剂石墨KS15,粘结剂丁苯橡胶(SBR)和羧甲基纤维素钠(CMC)按照质量比LMO∶CMC∶SBR∶石墨=86.5∶1∶2.5∶10在水中混合,形成均匀的正极浆料。正极集流体为PE导电膜与镀镍冲碳钢的复合材料,将正极浆料涂覆在正极集流体上形成活性物质层,随后将其进行压片,制成正极片,正极片厚度为0.4mm,正极活性物质面密度为750g/m2
负极包括55μm厚的锌箔,锌箔表面有铅镀层,铅镀层的质量与锌箔的质量比为700ppm。
电解液为2mol/L的硫酸锌和1mol/L的硫酸锂混合水溶液。
隔膜为AGM玻璃纤维,隔膜和负极尺寸与正极相当。
将5片正极和6片负极交错排列,正、负极之间以隔膜隔开,注入电解液至饱和,组装的电池的理论容量约5Ah,记作A1。
实施例1-2
与实施例1-1所不同的是,锌箔表面的铅镀层的质量与锌箔的质量比为300ppm,其他部分同实施例1-1,记作A2。
实施例1-3
与实施例1-1所不同的是,锌箔表面的铅镀层的质量与锌箔的质量比为1000ppm,其他部分同实施例1-1,记作A3。
实施例1-4
与实施例1-1所不同的是,锌箔表面的铅镀层的质量与锌箔的质量比为100ppm,其他部分同实施例1-1,记作A4。
实施例1-5
称取一定量的硫酸锌、硫酸锂溶于去离子水中,再向其中加入硫酸铅,硫酸锌和硫酸锂在电解液中的浓度分别为2mol/L和1mol/L,硫酸铅在电解液中的浓度为450ppm。
将配制好的电解液与2.5cm2锌箔的工作电极、泡沫镍对电极及饱和甘汞参比电极组成三电极体系电池,记作A5。
实施例1-6
与实施例1-5所不同的是,电解液中添加的硫酸铅的浓度为150ppm,其他部分同实施例1-5,记作A6。
实施例1-7
与实施例1-5所不同的是,电解液中添加的硫酸铅的浓度为75ppm,其他部分同实施例1-5,记作A7。
实施例1-8
与实施例1-5所不同的是,电解液中添加的硫酸铅的浓度为10ppm,其他部分同实施例1-5,记作A8。
实施例1-9
与实施例1-5所不同的是,电解液中添加的硫酸铅的浓度为1000ppm,其他部分同实施例1-5,记作A9。
对比例1-1
与实施例1-1所不同的是,电池的负极活性物质锌箔表面无铅镀层,其他部分同实施例1-1,记作D1。
对比例1-2
与实施例1-1所不同的是,电池的负极活性物质锌箔表面的铅镀层的质量与锌箔的质量比为1500ppm,其他部分同实施例1-1,记作D2。
对比例1-3
与实施例1-5所不同的是,三电极体系电池的电解液中未添加硫酸铅,其他部分同实施例1-5,记作D3。
性能测试
循环性能测试
在25℃下,对电池A1-A4及D1-D2以0.2C倍率进行恒流100DOD%循环充放电,电压范围为1.4-2.1V。
表1为电池A1-A4及D1-D2循环75次时相对于首次放电容量的容量保持率。由表1可见,电池的负极活性物质表面镀铅后,电池的循环性能得到提高,尤其当铅与锌箔的质量比在不大于1000ppm范围内,电池循环性能得到极大改善。
表1
电池 A1 A2 A3 A4 D1 D2
镀铅量/ppm 700 300 1000 100 0 1500
容量保持率/% 84 79 92 75 16 68
图1为电池A1及D1的放电容量、电池内阻与循环次数的关系曲线图。从图1也可以看出,电池A1的循环寿命相较于电池D1有很大改善。电池A1在循环至105次时,放电容量保持率约为80%,而D1在循环50次后,电池内阻明显升高,电池容量快速下降,循环至75次时,放电容量的保持率仅有16%左右。
上述结果表明当负极活性物质表面有铅镀层时,其能够有效抑制负极活性物质的枝晶的生长,减小电池的内阻,提高电池的循环寿命及放电容量。
计时安培测试
在-120mV的过电压下,对三电极体系电池A5-A9及D3进行1小时的计时安培测试。
图2为A5及D3中三电极体系电池的工作电极的绝对电流密度与时间的曲线。锌工作电极做为阴极,其绝对电流密度与锌电极上的金属沉积量有关。从图中可知D3与A5的锌电极经过1小时测试后的电流密度很接近,这就表明在这1小时内,D3与A5的锌电极上的金属 沉积量相当。但是A5中的锌电极在150s时,电流密度就能够稳定,而D3中的锌电极经过约1500s后电流密度才趋于稳定,这说明铅离子能够稳定锌离子的沉积过程。类似的现象可在A6-A9上观察到,只要电解液中添加铅离子,其阴极电流密度能够快速稳定,说明微量的铅离子就能对锌离子的沉积过程有促进作用。
SEM分析
在-120mV的过电压下,对三电极体系电池A5-A9及D3进行1小时的计时电流法测试,将测试过的工作电极用去离子水清洗,在室温下干燥,通过SEM表征工作电极的微观形貌。
图3-图6为A5-A7及D3经过1小时计时电流法测试后的工作电极的SEM图。从图中可以看出,当电解液中添加硫酸铅,锌离子在负极锌电极上的沉积层很均匀,沉积的金属颗粒小;而未添加硫酸铅的电解液,锌离子的沉积层不均匀,锌电极的某些部分无沉积层,某些部分沉积层厚,且明显存在大颗粒的枝晶,这表明铅离子能够改变锌离子在锌电极上的沉积晶面,使沉积层分布更均匀。
综上可知,当负极活性物质表面或电解液中有含铅物质时,负极活性物质的枝晶得到有效抑制,电池的循环性能及放电容量均能得到明显提高。
实施例2-1
本实施例的锰酸锂改性材料的分子式为LiMn2Pb0.05O4
本实施例的锰酸锂改性材料采用如下方法制备:
原料:将碳酸锂、四氧化三锰、硫酸铅按照摩尔比Li∶Mn∶Pb=1∶2∶0.05称重,并在酒精中混合。将混合均匀后的产物送入烧结炉中进行热处理,在空气气氛下,在700-850℃下热处理15-30小时。
得到锰酸锂改性材料LiMn2Pb0.05O4,记作a1。
实施例2-2
本实施例的锰酸锂改性材料的分子式为LiMn2Pb0.01O4
本实施例的锰酸锂改性材料采用如下方法制备∶
原料:将碳酸锂、四氧化三锰、硫酸铅按照摩尔比Li∶Mn∶Pb= 1∶2∶0.01称重,并在酒精中混合。将混合均匀后的产物送入烧结炉中,在空气气氛下,在700-850℃下热处理15-30小时。
得到锰酸锂改性材料LiMn2Pb0.01O4,记作a2。
实施例2-3
本实施例的锰酸锂改性材料的分子式为LiMn2Pb0.005O4
本实施例的锰酸锂改性材料采用如下方法制备:
原料:将碳酸锂、四氧化三锰、硫酸铅按照摩尔比Li∶Mn∶Pb=1∶2∶0.005称重,并在酒精中混合。将混合均匀后的产物送入烧结炉中,在空气气氛下,在700-850℃下热处理15-30小时。
得到锰酸锂改性材料LiMn2Pb0.005O4,记作a3。
实施例2-4
本实施例的锰酸锂改性材料的分子式为LiMn2Pb0.001O4
本实施例的锰酸锂改性材料采用如下方法制备:
原料:将碳酸锂、四氧化三锰、硫酸铅按照摩尔比Li∶Mn∶Pb=1∶2∶0.001称重,并在酒精中混合。将混合均匀后的产物送入烧结炉中,在空气气氛下,在700-850℃下热处理15-30小时。
得到锰酸锂改性材料LiMn2Pb0.001O4,记作a4。
对比例2-1
在对比例2-1中,没有对锰酸锂进行改性,锰酸锂材料的分子式为LiMn2O4,记作d1。
实施例2-5
将正极活性物质锰酸锂改性材料a1、导电剂石墨、粘结剂CMC和SBR按照质量比a1∶石墨∶CMC∶SBR=84.5∶12∶1∶2.5在水中混合,形成均匀的正极浆料。将正极浆料涂覆在正极集流体石墨箔上形成活性物质层,正极活性物质的面密度为20mg/cm2
负极包括50μm厚的负极活性物质锌箔和20μm厚的负极集流体黄铜箔。
AGM薄膜作为隔膜。
称取一定质量的硫酸锌、硫酸锂,加入水中溶解,配置成硫酸锌浓度为2mol/L、硫酸锂浓度为1mol/L的电解液。
将正极、负极以及隔膜组装成电芯,装入壳体内,然后注入电解液,封口,组装成容量为7mAh电池,记作B1。
实施例2-6
在实施例2-6中,正极活性物质采用锰酸锂改性材料a2,电池其余结构和制备方法同实施例2-5,组装成容量为7mAh电池,记作B2。
实施例2-7
在实施例2-7中,正极活性物质采用锰酸锂改性材料a3,电池其余结构和制备方法同实施例2-5,组装成容量为7mAh电池,记作B3。
实施例2-8
在实施例2-8中,正极活性物质采用锰酸锂改性材料a4,电池其余结构和制备方法同实施例2-5,组装成容量为7mAh电池,记作B4。
对比例2-2
在对比例2-2中,正极活性物质采用锰酸锂材料d1,电池其余结构和制备方法同实施例2-5,组装成容量为7mAh电池,记作S1。
性能测试
循环性能测试
将实施例2-5至2-8和对比例2-2中电池在常温下,以1C倍率在1.4V~2.1V电压范围内进行充放电循环测试。
表1为电池B2-B4及s1分别以1C循环100次、200次和300次时相对于首次放电容量的容量保持率。
表1
Figure PCTCN2016075706-appb-000001
由表1可见,电池正极活性物质采用铅改性的锰酸锂之后,电池的循环性能得到提高,虽然电池B1-B4相对于电池S1的容量保持率只提高了几个百分点,但由于电池S1本身的容量保持率不低,在此 基础上想要进一步提高的难度是巨大的。
自放电测试
以0.2C对实施例2-5至2-8和对比例2-2中电池进行恒流充电,充至2.1V后对电池进行恒压充电,限流0.2C至电流减少到0.O2C为止。将电池在60℃下搁置一天,待电池冷却至室温,测试电池的容量损失;将电池在60℃下搁置七天,待电池冷却至室温,测试电池的容量损失。
表2为电池B1-B4及S1在60℃下搁置一天、60℃下搁置二天和60℃下搁置三天的容量损失。
表2
Figure PCTCN2016075706-appb-000002
由表2可见,电池正极活性物质采用铅改性的锰酸锂之后,电池的容量损失是明显减小的,表明电池的自放电得到改善。
高温浮充试验
室温下,以0.2C对实施例2-5至2-8和对比例2-2中电池进行恒流充电,充至2.0V后再将电池在60℃下、2.0V浮充168h(一周),测试电池的浮充电流和浮充容量。
表3为电池B1-B4及S1在60℃下浮充168h的浮充电流和浮充容量。
表3
电池 浮充电流/mA 浮充容量/mAh
B1 0.045 8.8
B2 0.047 8.8
B3 0.042 8.7
B4 0.059 11.7
S1 0.07 13.5
由表3可见,电池正极活性物质采用铅改性的锰酸锂之后,电池浮充电流和浮充容量分别降低了15-40%和13-35%,这一结果进一步表明电池的自放电得到改善。
实施例2-9
在实施例2-9中,正极活性物质采用锰酸锂改性材料a4,正极其余结构和制备方法同实施例2-5。
负极包括50μm厚的负极活性物质锌箔,锌箔表面有镀铅层,镀铅层的质量与锌箔的质量比为700ppm。
AGM薄膜作为隔膜。
称取一定质量的硫酸锌、硫酸锂,加入水中溶解,配置成硫酸锌浓度为2mol/L、硫酸锂浓度为1mol/L的电解液。
将正极、负极以及隔膜组装成电芯,装入壳体内,然后注入电解液,封口,组装成容量为7mAh电池,记作B5。
实施例2-10
在实施例2-10中,负极锌箔表面有镀铅层,镀铅层的质量与锌箔的质量比为300ppm。电池其余构成和制备方法同实施例2-9,组装成容量为7mAh电池,记作B6。
实施例2-11
在实施例2-11中,负极锌箔表面有镀铅层,镀铅层的质量与锌箔的质量比为100ppm。电池其余构成和制备方法同实施例2-9,组装成容量为7mAh电池,记作B7。
实施例2-12
在实施例2-12中,电解液中添加有硫酸铅,硫酸铅的浓度为150ppm。电池其余构成和制备方法同实施例2-9,组装成容量为7mAh电池,记作B8。
性能测试
循环性能测试
将实施例2-9至2-12中电池B5-B8在常温下,以1C倍率在1.4V~2.1V电压范围内进行充放电循环测试。
电池B5-B8循环100次具有高于电池B4的容量保持率。这一结果说明:当负极活性物质表面或电解液中有含铅物质时,负极活性物质的枝晶得到有效抑制,电池的循环性能得到进一步的提高。
实施例3-1
在本实施例的复合正极材料中,正极活性物质为锰酸锂LiMn2O4,包覆层为铅,复合正极材料为铅包覆的锰酸锂,其中,铅与锰酸锂的质量百分比为5%。
本实施例的锰酸锂改性材料采用如下方法制备:
原料:将醋酸铅、锰酸锂按照质量比5∶100称重,并在去离子水中混合,搅拌。使包覆材料均匀包覆在正极活性物质锰酸锂颗粒表面,将混合均匀后的产物进行干燥,将干燥后的固体材料在400-650℃下烧结15-30h。
实施例3-2
在本实施例的复合正极材料中,正极活性物质为锰酸锂LiMn2O4,包覆层为铅,复合正极材料为铅包覆的锰酸锂,其中,铅与锰酸锂的质量百分比为1%。
本实施例的锰酸锂改性材料采用如下方法制备:
原料:将醋酸铅、锰酸锂按照质量比1∶100称重,并在去离子水中混合,搅拌。使包覆材料均匀包覆在正极活性物质锰酸锂颗粒表面,将混合均匀后的产物进行干燥,将干燥后的固体材料在400-650℃下烧结15-30h。
实施例3-3
在本实施例的复合正极材料中,正极活性物质为锰酸锂LiMn2O4,包覆层为铅,复合正极材料为铅包覆的锰酸锂,其中,铅与锰酸锂的质量百分比为0.5%。
本实施例的锰酸锂改性材料采用如下方法制备:
原料:将醋酸铅、锰酸锂按照质量比0.5∶100称重,并在去离子 水中混合,搅拌。使包覆材料均匀包覆在正极活性物质锰酸锂颗粒表面,将混合均匀后的产物进行干燥,将干燥后的固体材料在400-650℃下烧结15-30h。
实施例3-4
在本实施例的复合正极材料中,正极活性物质为锰酸锂LiMn2O4,包覆层为铅,复合正极材料为铅包覆的锰酸锂,其中,铅与锰酸锂的质量百分比为0.1%。
本实施例的锰酸锂改性材料采用如下方法制备:
原料:将醋酸铅、锰酸锂按照质量比0.1∶100称重,并在去离子水中混合,搅拌。使包覆材料均匀包覆在正极活性物质锰酸锂颗粒表面,将混合均匀后的产物进行干燥,将干燥后的固体材料在400-650℃下烧结15-30h。
对比例3-1
在对比例3-1中,正极活性物质为锰酸锂LiMn2O4,没有对锰酸锂进行包覆。
实施例3-5
将实施例3-1中复合正极材料、导电剂石墨、粘结剂CMC和SBR按照质量比复合正极材料∶石墨∶CMC∶SBR=84.5∶12∶1∶2.5在水中混合,形成均匀的正极浆料。将正极浆料涂覆在正极集流体石墨箔上形成活性物质层,正极活性物质的面密度为20mg/cm2
负极包括50μm厚的负极活性物质锌箔和20μm厚的负极集流体黄铜箔。
AGM薄膜作为隔膜。
称取一定质量的硫酸锌、硫酸锂,加入水中溶解,配置成硫酸锌浓度为2mol/L、硫酸锂浓度为1mol/L的电解液。
将正极、负极以及隔膜组装成电芯,装入壳体内,然后注入电解液,封口,组装成容量为7mAh电池,记作C1。
实施例3-6
实施例3-6中采用实施例3-2中复合正极材料,电池其余结构和制备方法同实施例3-5,组装成容量为7mAh电池,记作C2。
实施例3-7
实施例3-7中采用实施例3-3中复合正极材料,电池其余结构和制备方法同实施例3-5,组装成容量为7mAh电池,记作C3。
实施例3-8
实施例3-8中采用实施例3-4中复合正极材料,电池其余结构和制备方法同实施例3-5,组装成容量为7mAh电池,记作C4。
对比例3-2
对比例3-2中采用对比例3-1中复合正极材料,电池其余结构和制备方法同实施例3-5,组装成容量为7mAh电池,记作E1。
性能测试
循环性能测试
将实施例3-5至3-8和对比例3-2中电池在常温下,以1C倍率在1.4V~2.1V电压范围内进行充放电循环测试。
表4为电池C1-C4及E1分别以1C循环100次、200次和300次时相对于首次放电容量的容量保持率。
表4
Figure PCTCN2016075706-appb-000003
由表4可见,电池正极采用复合正极材料之后,电池的循环性能得到提高。
高温浮充试验
室温下,以0.2C对实施例3-5至3-8和对比例3-2中电池进行恒流充电,充至2.0V后再将电池在60℃下、2.0V浮充168h(一周),测试电池的浮充电流和浮充容量。
表5为电池C1-C4及E1在60℃下浮充168h的浮充电流和浮充容量。
表5
电池 浮充电流/mA 浮充容量/mAh
C1 0.047 9.8
C2 0.049 9.9
C3 0.050 10.0
C4 0.065 13.0
E1 0.070 13.5
由表5可见,电池正极采用复合正极材料之后,电池浮充电流和浮充容量分别降低了7-33%和4-27%,这一结果进一步表明电池的自放电得到改善。
实施例3-9
实施例3-9中采用实施例3-4中复合正极材料,正极其余结构和制备方法同实施例3-5。
负极包括50μm厚的负极活性物质锌箔,锌箔表面有镀铅层,镀铅层的质量与锌箔的质量比为700ppm。
AGM薄膜作为隔膜。
称取一定质量的硫酸锌、硫酸锂,加入水中溶解,配置成硫酸锌浓度为2mol/L、硫酸锂浓度为1mol/L的电解液。
将正极、负极以及隔膜组装成电芯,装入壳体内,然后注入电解液,封口,组装成容量为7mAh电池,记作C5。
实施例3-10
在实施例3-10中,负极锌箔表面有镀铅层,镀铅层的质量与锌箔的质量比为300ppm。电池其余构成和制备方法同实施例3-9,组装成容量为7mAh电池,记作C6。
实施例3-11
在实施例3-11中,负极锌箔表面有镀铅层,镀铅层的质量与锌箔的质量比为100ppm。电池其余构成和制备方法同实施例3-9,组装成容量为7mAh电池,记作C7。
实施例3-12
在实施例3-12中,电解液中添加有硫酸铅,硫酸铅的浓度为150ppm。电池其余构成和制备方法同实施例3-9,组装成容量为7mAh电池,记作C8。
实施例3-13
在本实施例的复合正极材料中,正极活性物质为锰酸锂LiMn2O4,包覆层为铅,复合正极材料为一氧化铅包覆的锰酸锂,其中,一氧化铅中的铅与锰酸锂的质量百分比为0.1%。
本实施例的锰酸锂改性材料采用如下方法制备:
原料:将一氧化铅、锰酸锂按照质量比0.1∶100称重,并在去离子水中混合,搅拌。使包覆材料均匀包覆在正极活性物质锰酸锂颗粒表面,将混合均匀后的产物进行干燥,将干燥后的固体材料在400-650℃下烧结15-30h。
将制备的复合正极材料、导电剂石墨、粘结剂CMC和SBR按照质量比复合正极材料∶石墨∶CMC∶SBR=84.5∶12∶1∶2.5在水中混合,形成均匀的正极浆料。将正极浆料涂覆在正极集流体石墨箔上形成活性物质层,正极活性物质的面密度为20mg/cm2
负极包括50μm厚的负极活性物质锌箔和20μm厚的负极集流体黄铜箔。
AGM薄膜作为隔膜。
称取一定质量的硫酸锌、硫酸锂,加入水中溶解,配置成硫酸锌浓度为2mol/L、硫酸锂浓度为1mol/L的电解液。
将正极、负极以及隔膜组装成电芯,装入壳体内,然后注入电解液,封口,组装成容量为7mAh电池,记作C9。
性能测试
循环性能测试
将实施例3-9至3-13中电池C5-C9在常温下,以1C倍率在1.4V~2.1V电压范围内进行充放电循环测试。
电池C5-C8循环100次具有高于电池C4的容量保持率。这一结果说明:当负极活性物质表面或电解液中有含铅物质时,负极活性物质的枝晶得到有效抑制,电池的循环性能得到进一步的提高。
电池C9循环100次的容量保持率略低于电池C4的容量保持率, 高于电池E1的容量保持率,这一结果说明电池正极采用复合正极材料一氧化铅包覆的锰酸锂,电池的循环性能也得到了改善。
尽管发明人已经对本发明的技术方案做了较详细的阐述和列举,应当理解,对于本领域技术人员来说,对上述实施例作出修改和/或变通或者采用等同的替代方案是显然的,都不能脱离本发明精神的实质,本发明中出现的术语用于对本发明技术方案的阐述和理解,并不能构成对本发明的限制。

Claims (15)

  1. 一种电池,包括正极、负极及电解液,所述正极包括正极活性物质和正极集流体;所述电解液包括第一金属离子和第二金属离子,充放电过程中,所述第一金属离子能够在所述正极可逆脱出-嵌入,所述第二金属离子在所述负极能够还原沉积为第二金属且第二金属能可逆氧化溶解为第二金属离子;所述负极包括负极活性物质和负极集流体;其特征在于:所述负极活性物质表面或/和电解液中有含铅物质,且所述含铅物质中的铅与所述电池的质量比不大于1000ppm。
  2. 根据权利要求1所述的电池,其特征在于:所述负极活性物质表面中含铅物质包括铅金属。
  3. 根据权利要求1所述的电池,其特征在于:所述电解液中含铅物质包括铅离子。
  4. 根据权利要求1或3所述的电池,其特征在于:所述电解液中含铅物质中的铅与电解液的质量比不小于10ppm。
  5. 根据权利要求1所述的电池,其特征在于:所述含铅物质包括金属铅、硫酸铅和氧化铅中的至少一种。
  6. 根据权利要求1所述的电池,其特征在于:所述电池包括添加剂铋化合物,所述铋化合物添加在所述负极和/或所述电解液中。
  7. 根据权利要求1所述的电池,其特征在于:所述负极活性物质包括锌,所述负极集流体包括黄铜箔。
  8. 根据权利要求1所述的电池,其特征在于:所述正极集流体包括尼龙网载体和包覆在所述尼龙网载体上的石墨箔。
  9. 根据权利要求1所述的电池,其特征在于:所述第一金属离子包括锂离子、钠离子或镁离子,所述第二金属离子包括锌离子。
  10. 根据权利要求1所述的电池,其特征在于:所述正极活性物质包括锰酸锂改性材料,所述锰酸锂改性材料符合通式Li1+xMnyMzOk,其中,M选自Pb,-1≤x≤0.5,1≤y≤2.5,0<z≤0.1,3≤k≤6。
  11. 根据权利要求10所述的电池,其特征在于:所述锰酸锂改性材料表面还包覆有金属铅和/或氧化铅。
  12. 根据权利要求1所述的电池,其特征在于:所述正极活性物质表面具有包覆层,所述包覆层为金属铅和/或氧化铅。
  13. 根据权利要求12所述的电池,其特征在于:所述金属铅和/或氧化铅中的铅与所述正极活性物质的质量百分比范围为0.001%-10%。
  14. 一种电池组,包括若干个如权利要求1-13中任意一项所述的电池。
  15. 一种不间断电源,包括如权利要求1-13中任意一项所述的电池。
PCT/CN2016/075706 2015-03-06 2016-03-04 电池、电池组和不间断电源 WO2016141861A1 (zh)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US15/556,277 US10522869B2 (en) 2015-03-06 2016-03-04 Battery, battery pack, and uninterruptible power supply
EP16761088.0A EP3267518B1 (en) 2015-03-06 2016-03-04 Battery, battery pack and uninterruptible power supply
US16/680,286 US11211635B2 (en) 2015-03-06 2019-11-11 Battery, battery pack, and uninterruptible power supply

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201510100127.5A CN105990582A (zh) 2015-03-06 2015-03-06 电池
CN201510100127.5 2015-03-06

Related Child Applications (2)

Application Number Title Priority Date Filing Date
US15/556,277 A-371-Of-International US10522869B2 (en) 2015-03-06 2016-03-04 Battery, battery pack, and uninterruptible power supply
US16/680,286 Continuation US11211635B2 (en) 2015-03-06 2019-11-11 Battery, battery pack, and uninterruptible power supply

Publications (1)

Publication Number Publication Date
WO2016141861A1 true WO2016141861A1 (zh) 2016-09-15

Family

ID=56880010

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2016/075706 WO2016141861A1 (zh) 2015-03-06 2016-03-04 电池、电池组和不间断电源

Country Status (4)

Country Link
US (2) US10522869B2 (zh)
EP (1) EP3267518B1 (zh)
CN (1) CN105990582A (zh)
WO (1) WO2016141861A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11211635B2 (en) 2015-03-06 2021-12-28 Positec Power Tools (Suzhou) Co., Ltd. Battery, battery pack, and uninterruptible power supply

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3033328A1 (fr) * 2015-03-05 2016-09-09 Arkema France Composition liquide de nanocharges carbonees pour les formulations utilisees dans les batteries au plomb.
KR102564469B1 (ko) * 2016-04-14 2023-08-08 삼성전자주식회사 배터리 보호 방법 및 장치
US20210367229A1 (en) * 2020-05-19 2021-11-25 Global Graphene Group, Inc. Conducting polymer network/expanded graphite-enabled negative electrode for a lithium-ion battery
JPWO2022254975A1 (zh) * 2021-06-03 2022-12-08
JPWO2022254974A1 (zh) * 2021-06-03 2022-12-08

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1501539A (zh) * 2002-11-16 2004-06-02 ����Sdi��ʽ���� 非水电解液及使用它的锂电池
CN1744352A (zh) * 2004-08-30 2006-03-08 新神户电机株式会社 正极活性材料、非水电解质二次电池和正极活性材料的制造方法
CN101373829A (zh) * 2008-10-07 2009-02-25 深圳市贝特瑞新能源材料股份有限公司 钛系负极活性物质及其制备方法、钛系锂离子动力电池
CN101877407A (zh) * 2009-04-30 2010-11-03 比亚迪股份有限公司 一种负极活性物质以及制备方法及电池
CN103094627A (zh) * 2011-11-03 2013-05-08 苏州宝时得电动工具有限公司 电池

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5582935A (en) * 1995-09-28 1996-12-10 Dasgupta; Sankar Composite electrode for a lithium battery
US6303250B1 (en) * 1999-04-09 2001-10-16 Matsushita Electric Industrial Co., Ltd. Secondary battery including an electrolytic solution with an organic additive
US8518603B2 (en) * 2005-12-05 2013-08-27 Nanotek Instruments, Inc. Sheet molding compound flow field plate, bipolar plate and fuel cell
EP2419952B1 (en) * 2009-04-15 2014-06-04 Suren Martirosyan Electrically rechargeable battery with zn electrode, and method for manufacturing said battery
WO2011079482A1 (zh) 2009-12-29 2011-07-07 万向电动汽车有限公司 一种电池
WO2012061449A1 (en) * 2010-11-03 2012-05-10 Zpower, Llc Novel electrodes and rechargeable batteries
CN102479968B (zh) * 2010-11-29 2014-06-11 中国科学院大连化学物理研究所 一种锌/多卤化物储能电池
KR101758967B1 (ko) 2011-06-03 2017-07-17 포시텍 파워 툴스(소주) 컴퍼니. 리미티드. 전지
US10873090B2 (en) * 2011-07-06 2020-12-22 Research Foundation Of The City University Of New York Reduced-area current collectors for rechargeable batteries
EP2953190B1 (en) * 2013-02-01 2019-05-22 Nippon Shokubai Co., Ltd. Electrode precursor, electrode, and battery
CN103060846B (zh) * 2013-02-15 2015-05-20 桂林理工大学 脉冲电沉积制备Zn-Pb-Bi-La合金电极材料的方法
EP3016199B1 (en) * 2013-06-28 2019-01-09 Positec Power Tools (Suzhou) Co., Ltd Electrolytic solution and battery
CN104282910A (zh) * 2013-07-12 2015-01-14 苏州宝时得电动工具有限公司 电池
CN105990582A (zh) 2015-03-06 2016-10-05 苏州宝时得电动工具有限公司 电池

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1501539A (zh) * 2002-11-16 2004-06-02 ����Sdi��ʽ���� 非水电解液及使用它的锂电池
CN1744352A (zh) * 2004-08-30 2006-03-08 新神户电机株式会社 正极活性材料、非水电解质二次电池和正极活性材料的制造方法
CN101373829A (zh) * 2008-10-07 2009-02-25 深圳市贝特瑞新能源材料股份有限公司 钛系负极活性物质及其制备方法、钛系锂离子动力电池
CN101877407A (zh) * 2009-04-30 2010-11-03 比亚迪股份有限公司 一种负极活性物质以及制备方法及电池
CN103094627A (zh) * 2011-11-03 2013-05-08 苏州宝时得电动工具有限公司 电池

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3267518A4 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11211635B2 (en) 2015-03-06 2021-12-28 Positec Power Tools (Suzhou) Co., Ltd. Battery, battery pack, and uninterruptible power supply

Also Published As

Publication number Publication date
EP3267518A4 (en) 2018-10-03
US11211635B2 (en) 2021-12-28
US20200083556A1 (en) 2020-03-12
EP3267518B1 (en) 2020-11-18
CN105990582A (zh) 2016-10-05
US20180048016A1 (en) 2018-02-15
EP3267518A1 (en) 2018-01-10
US10522869B2 (en) 2019-12-31

Similar Documents

Publication Publication Date Title
US11211635B2 (en) Battery, battery pack, and uninterruptible power supply
WO2017020860A1 (zh) 电池、电池组以及不间断电源
CN111463403A (zh) 复合人工固态电解质界面膜修饰的负极材料及其电池应用
CN103107373B (zh) 电池
CN104882637B (zh) 电解液和电化学储能装置
CN105336993A (zh) 电解液和电池
CN106328950A (zh) 正极材料及电池
CN104766994A (zh) 电池
CN104752681A (zh) 电池
CN104766971A (zh) 正极材料,含有正极材料的水系电池
CN105742637A (zh) 正极材料、含有该正极材料的电池
CN109119635B (zh) 电池
CN108963241B (zh) 电池、电池组以及不间断电源
WO2016045622A1 (zh) 电池、电池组和不间断电源
CN104282952B (zh) 电解液及电池
CN104733787B (zh) 电池
WO2017177960A1 (zh) 电解液、电池和电池组
CN105449294A (zh) 电池
CN109273670A (zh) 一种具有高比表面介孔保护膜的金属锂负极及其制备方法
CN108666575A (zh) 复合导电剂及其制备方法、正极和电池
WO2016202276A1 (zh) 正极材料及电池
WO2023134234A1 (zh) 正极复合材料、其制备方法、正极以及锂离子二次电池
CN105336956A (zh) 电池
CN213150817U (zh) 一种铜集流体
CN104934634B (zh) 电池

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 16761088

Country of ref document: EP

Kind code of ref document: A1

REEP Request for entry into the european phase

Ref document number: 2016761088

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 15556277

Country of ref document: US

NENP Non-entry into the national phase

Ref country code: DE