33results about How to "Solve capacity fading" patented technology

The invention relates to use of a crosslinking type polybenzimidazole porous separating membrane in a liquid flow battery, and the porous membrane material is a crosslinking type polybenzimidazole polymer material. The porous membrane prepared by the invention is used in the liquid flow battery, by use of a cross-linking method and controlling of the crosslinking reaction, the membrane material oxidation stability and ion selectivity can be improved, the function of an ion exchange membrane in the liquid flow battery can be realized, the problem of capacity attenuation of a porous diaphragm can be effectively solved, the aperture of the porous membrane can be further regulated by change of variety of the polymer and the crosslinking agent of the composite membrane, ion selectivity of the porous membrane can be effectively improved, and the membrane material has the advantages of simple preparation method, controllable pore size, low cost, and easy implementation of large batch production.

The invention provides a flow battery system and a capacity re-balance method for a flow battery. The flow battery system comprises a flow battery unit, a positive electrode electrolyte storage tank and a negative electrode electrolyte storage tank; the flow battery system also comprises a co-mixing equipartition module; the co-mixing equipartition module comprises an electrolyte co-mixing unit and an electrolyte equipartition unit, wherein the electrolyte co-mixing unit is connected with a positive electrode outlet, a negative electrode outlet, the inlet of the positive electrode electrolyte storage tank and the inlet of the negative electrode electrolyte storage tank separately for co-mixing the electrolyte in the positive electrode electrolyte storage tank and the negative electrode electrolyte storage tank; and the electrolyte equipartition unit is connected with the outlet of the positive electrode electrolyte storage tank, the outlet of the negative electrode electrolyte storage tank, a positive electrode inlet and a negative electrode inlet for performing equipartition on the electrolyte in the positive electrode electrolyte storage tank and the negative electrode electrolyte storage tank. By performing co-mixing and equipartition treatment on the positive and negative electrode electrolyte, the problem of capacity fading caused by imbalance of vanadium ion total quantity in the positive and negative electrode electrolyte and the problem of electrolyte volume imbalance caused by water migration are solved.

A system for evaluating a redox flow battery according to an embodiment of the present disclosure includes: a control unit configured to control the path of a flow channel connected between a detection cell and the redox flow battery or a flow channel connected between the detection cell and an agitator; and an evaluation unit configured to evaluate any one of the state of charge, capacity fade and oxidation number balance of an electrolyte, which is used in the redox flow battery, by measuring a current or voltage of the detection cell based on the controlling of the path by the control unit. According to the present disclosure, the capacity fade problem of a redox flow battery can be quickly coped with by evaluating the information of the positive and negative electrode electrolytes on battery capacity fade and information about the valence balance of the electrolytes in situ.

The invention belongs to the field of large-scale electrical energy storage of liquid metal batteries, and discloses a temperature regulation method for reducing battery capacity attenuation and lowering energy consumption by reducing the temperature of an electric pile in a suspend mode of a liquid metal battery in energy storage application. The temperature regulation method comprises the following steps: (a), detecting the temperature of the liquid metal battery by using temperature detecting equipment to obtain the current temperature thereof; (b), reducing the current temperature of the liquid metal battery and monitoring the current temperature in real time, and converting electrodes and an electrolyte in the liquid metal battery from a liquid phase to a colloidal state or solid phase so as to reduce the solubility of the electrodes in the electrolyte and lower the energy consumption of the liquid metal battery; (c), when the current operating temperature is reduced to 25 DEG C to the operating working temperature range, stopping reduction in the current operating temperature, and meanwhile maintaining the final temperature of the liquid metal battery at the current operatingtemperature. By the temperature regulation method, the battery capacity attenuation in the suspend mode of the liquid metal battery is reduced and additional electrical energy loss is reduced.

The invention belongs to the field of large-scale electrical energy storage of liquid metal batteries, and discloses a temperature regulation method for reducing battery capacity attenuation and lowering energy consumption by reducing the temperature of an electric pile in a suspend mode of a liquid metal battery in energy storage application. The temperature regulation method comprises the following steps: (a), detecting the temperature of the liquid metal battery by using temperature detecting equipment to obtain the current temperature thereof; (b), reducing the current temperature of the liquid metal battery and monitoring the current temperature in real time, and converting electrodes and an electrolyte in the liquid metal battery from a liquid phase to a colloidal state or solid phase so as to reduce the solubility of the electrodes in the electrolyte and lower the energy consumption of the liquid metal battery; (c), when the current operating temperature is reduced to 25 DEG C to the operating working temperature range, stopping reduction in the current operating temperature, and meanwhile maintaining the final temperature of the liquid metal battery at the current operatingtemperature. By the temperature regulation method, the battery capacity attenuation in the suspend mode of the liquid metal battery is reduced and additional electrical energy loss is reduced.

The invention discloses an electrolyte for a flow battery and a polyhalide-chromium flow battery. The electrolyte for the flow battery is prepared by reacting cheap and easily available chromium hydroxide with hydrochloric acid and hydrobromic acid. Before charging (the state of charge is 0%), the components of the positive and negative electrolyte are consistent, and include trivalent chromium ions, chloride ions, bromide ions and hydrogen ions. The electrolyte has the beneficial effects that: the electrolyte for the flow battery has the advantages of high energy density, low cost, high charging and discharging performance, long cycle life, wide operating temperature interval and the like, and has a wide application prospect in the field of fixed large-scale power storage.

The invention discloses a preparation method of a flexible lithium ion battery and a network lithium titanate electrode structure. The preparation method of the flexible lithium-ion battery includes: growing a network lithium titanate on a titanium sheet as a negative electrode material; making a coated lithium manganate nanorod as a positive electrode material; The sandwich shape is stacked together and placed in the middle of two layers of polydimethylsiloxane PDMS films for packaging to complete the preparation of flexible lithium-ion batteries. The flexible lithium-ion battery disclosed in the present invention adopts network-structured lithium titanate, which can make full use of the advantages of the one-dimensional structure and the three-dimensional network structure, and increase the contact area between the active material and the electrolyte. The flexible lithium-ion battery disclosed by the invention can maintain high stability in a bent state, and realize dozens of charging and discharging cycles.

The invention discloses a charge-discharge control method and system of a redox flow battery and the redox flow battery. The method comprises the following steps of 1, detecting SOC of the redox flow battery; 2, judging whether the SOC of the redox flow battery is between an SOC lower limit and an SOC upper limit or not, if yes, executing the step 3, otherwise executing the step 4; 3, maintaining a voltage of the redox flow battery unchanged; and 4, adjusting the voltage of the redox flow battery to be lower than a first preset voltage when the SOC of the redox flow battery is larger than or equal to the SOC upper limit, and adjusting the voltage of the redox flow battery to be between the first preset voltage and a second preset voltage when the SOC of the redox flow battery is smaller than or equal to the SOC lower limit, wherein the second preset voltage is higher than the first preset voltage. By the method, the problems of side reaction is easy to generate in the redox flow battery under a high SOC condition and capacity attenuation of the redox flow battery caused by high SOC charge for a long time are prevented, and meanwhile, the upper limit of a charging voltage can be increased under a low SOC condition so as to improve charging quantity.

The invention discloses a silicon-carbon negative electrode material for lithium-ion batteries, which has a ring structure with an outer diameter of 2-15 μm and an inner diameter of 0.5-5 μm; Agglomerated silicon particles. The invention also discloses a preparation method of the material, comprising: step 1: preparing a polymer solution; step 2: adding an organic carbon source to the polymer solution; step 3: adding silicon powder to the polymer solution to prepare a suspension; Step 4: transfer the suspension to a sand mill for sand grinding; Step 5: add a dispersant to the sand-milled suspension and stir evenly; spray dry to obtain a black powder; Step 6: dry the black powder in an argon atmosphere heat treatment. The hollow ring structure of the lithium ion negative electrode silicon carbon material with a ring structure of the present invention solves the problem of capacity attenuation caused by volume expansion in the cycle process, and has high initial charge and discharge efficiency, high specific capacity, and stable cycle performance.

The invention discloses a preparation of a composite porous membrane for a flow battery and its application in a flow battery, which is prepared from one or more than two kinds of organic polymer resin or sulfonated polymer resin as raw materials The porous membrane is used as a matrix, and cationic and anionic organic resins are respectively compounded on both sides of the matrix to form a composite porous membrane. The preparation method of this type of composite membrane is simple, the process is environmentally friendly, the thickness of the assembled layer is controllable, and the ion selectivity is adjustable. Compared with the original porous diaphragm membrane, the composite membrane has better ion conductivity and vanadium ion barrier ability, and the ion selectivity is greatly improved. In addition, the composite membrane can effectively inhibit the migration of electrolyte solution and solve the problem of capacity fading.

An embodiment of the present invention provides a positive electrode active material, including secondary particles formed by densely packing a plurality of primary particles, the interior of the primary particles includes closed pores, the size of the closed pores is in the range of 1nm-300nm, and the primary particles contain the compound Li c Ni a co b m 1‑a‑ b o 2‑d x d , wherein, M is selected from one or more of Mn, Al, Na, Mg, Ca, Zr, Sr, Ti, Cr, V, W, Si, Ga, Sn, lanthanides and actinides, and X is selected from From one or more of B, F, Cl and S, 0≤a≤1, 0≤b≤1, 0.8≤c≤1.5, 0≤d≤0.5. The closed pores inside the primary particles of the positive electrode active material can effectively release the internal stress caused by the volume change of the material during the lithium intercalation and deintercalation process, and improve the cycle stability of the positive electrode active material. The embodiment of the present invention also provides a preparation method of the positive electrode active material and a lithium secondary battery.

The invention discloses an electrolyte storage tank, a redox flow battery, a box-type redox flow battery system and a charge-discharge control method of redox flow battery. A ring tube I and a ring tube II are arranged in the electrolyte storage tank, wherein the ring tube II communicates with an electrolyte return hole, the ring tube I communicates with an electrolyte output, the annular perimeter of the ring tube I is not equal to the annular perimeter of the ring tube II, and a plurality of liquid holes are formed in tube walls of both of the annular tube I and the annular tube II. By a multi-layer ring tube structure in the storage tank, an electrolyte flowing dead zone of an electrolyte in the storage tank is greatly reduced, the flowing of the electrolyte is more uniform, and the utilization of the electrolyte is effectively improved; and moreover, since the longitudinal distance between the electrolyte output and the electrolyte return hole is reduced, the problem of SOC lag is effectively solved, and the SOC monitoring accuracy of the redox flow battery is improved.

The invention provides non-aqueous electrolyte for a lithium ion battery and a lithium ion secondary battery prepared from the non-aqueous electrolyte. The non-aqueous electrolyte for the lithium ion battery comprises cyclic carboxylic ester and / or cyclic carbonate ester, cyclic sulfate, an electrolyte salt, fluoroether with the following structural formula: Rf1-O-Rf2, and a fluorocarbon surfactant, wherein the Rf1 is a fluorine-containing alkyl group of which the carbon atom number is 3 to 4; the Rf2 is a fluorine-containing alkyl group of which the carbon atom number is 2 to 5; the mass percentage of the fluoroether in the electrolyte is 10 to 50 percent; and the fluorocarbon surfactant is used for further improving the performances of the battery. The high temperature performance and the safety of the lithium ion secondary battery prepared from the non-aqueous electrolyte can be kept at a higher level as a whole, and the cycling performance is improved.

The invention provides a charging control method for a battery pack, and the method comprises the steps: determining a first charging voltage Un of a target battery in the battery pack in the nth charging and discharging cycle, the target battery being a single battery with the highest voltage in the charging process of the nth charging and discharging cycle of the battery pack; determining a second charging voltage UF of the target battery in the nth charge-discharge cycle; in the (n + m) th charging and discharging cycle, the smaller one of the first charging voltage Un and the second charging voltage UF is used as the charging cut-off voltage of each single battery in the battery pack in the charging process, and m is a preset integer larger than or equal to 1. According to the charging control method of the battery pack, the electronic device and the storage medium, the cycle performance of the battery pack can be improved.

The present disclosure relates to a method for pretreating a nano-hollow silicon / carbon electrode material of an electrochemical energy storage device with a solvent and solvent-in-silicon particles. Nano-scale silicon-in-solvent particles pretreated by the method of the present disclosure, a method for preparing an electrode using the nano-scale silicon-in-solvent particles, an electrode prepared by the electrode preparation method, and an electrochemical device comprising the electrode. energy storage device. The method according to the present disclosure solves the delamination phenomenon caused by the low density of hollow silicon in the conventional mixing process. Therefore, in further charge and discharge tests, the conductivity of the pole piece is significantly improved, and the performance of the battery is significantly improved. In the disclosed method, the solvent is used as the filler of the hollow structure, and no additional impurities and by-products will be introduced. When water is used as the filling agent, the source of water is extensive, the cost is low, and the operation process is simple. Therefore, the pretreatment process is very suitable for industrial production.

The invention belongs to the technical field of inorganic material preparation and battery materials, and relates to a carbon-oxygen double-doped porous hollow bowl-shaped carbon material and a preparation method thereof. The material is a carbonaceous bowl-shaped structure particle with high dispersibility and narrow particle size distribution , the particle size is controllable, there is a hollow structure inside the particle, the shape is a concave bowl, the wall thickness is controllable, there are many holes on the wall of the bowl, the holes include micropores and mesopores, and the specific surface area is high; it has nitrogen and oxygen double doping characteristics. Potassium ion battery anode for high volume specific capacity and cycle stability. Potassium-ion batteries are considered to be one of the candidates to replace traditional high-priced lithium-ion batteries due to their abundant global reserves of potassium and low redox voltage values. However, the large size of potassium ions results in a lack of specific capacity for potassium-ion batteries. High electrode material with good cycle stability and rate performance. The material of the invention is used for the electrode of the potassium ion battery, and achieves the purpose of enhancing the stability of the potassium ion battery, improving the rate performance, and simultaneously improving the volume specific capacity of the battery.