Nickel-based Prussian blue battery positive electrode material, preparation method thereof and battery

Abstract

The invention discloses a nickel-based Prussian blue battery positive electrode material, a preparation method of the nickel-based Prussian blue battery positive electrode material and a battery, and belongs to the technical field of batteries, and the preparation method of the nickel-based Prussian blue battery positive electrode material comprises the following steps: dissolving sodium citrate into a nickel chloride solution to obtain a reagent A; dissolving sodium ferrocyanide in water to prepare a solution to obtain a reagent B; dissolving polyvinylpyrrolidone in a sodium chloride solution to obtain a reagent C; slowly dropwise adding the reagent A and the reagent B into the reagent C at the same time to obtain a turbid liquid, and aging the turbid liquid; centrifugally separating, washing, drying and grinding the aged turbid liquid to obtain the nickel-based Prussian blue battery positive electrode material; the nickel-based Prussian blue battery positive electrode material prepared by the invention has the characteristics of high capacity, low alternating-current impedance and high long-cycle stability, and has excellent electrochemical performance.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of batteries, and particularly relates to a nickel-based Prussian blue battery positive electrode material, a preparation method thereof and a battery. BACKGROUND

[0002] Due to the depletion of traditional fossil energy and environmental problems caused by its use, humans urgently need to research and develop new clean energy to support daily life and production needs and promote the sustainable development of social energy. Lithium ion batteries are widely used in the energy storage field, but lithium resources are limited and unevenly distributed, and the mining difficulty is gradually increasing. Sodium ion batteries are considered as an ideal alternative system for lithium ion batteries because of the abundant resources and low cost, and have great potential in large-scale energy storage.

[0003] As a highly potential energy source, sodium ion batteries have received extensive attention from academia and industry in recent years. With the continuous breakthroughs in material science, especially the development of new positive and negative electrode materials, the performance of sodium ion batteries has been significantly improved, and they have become a research hotspot again.

[0004] Nowadays, sodium ion batteries have been preliminarily applied in low-speed electric vehicles, energy storage systems and other fields, showing good development potential. However, there is still a certain gap between sodium ion batteries and lithium ion batteries in terms of energy density, cycle life and other performance, and there are still many challenges in the optimization of electrode materials, improvement of battery manufacturing process and integration of battery systems, which need further research and technological breakthroughs. SUMMARY

[0005] An object of the present application is to solve at least the above problems and / or drawbacks, and to provide at least the advantages set out hereinafter.

[0006] To achieve these objects and other advantages and in view of prior art, a preparation method of a nickel-based Prussian blue battery positive electrode material is provided, which comprises the following steps: Step one, dissolve sodium citrate into a nickel chloride solution to obtain reagent A, dissolve sodium ferrocyanide in water to prepare a solution to obtain reagent B, and dissolve polyvinylpyrrolidone (PVP) in a sodium chloride solution to obtain reagent C; Step two, reagent A and reagent B are simultaneously and slowly added to reagent C at room temperature, and reagent C is continuously stirred until reagent A and reagent B are completely added to reagent C, to obtain a suspension, and the obtained suspension is aged; Step three, the suspension after aging is centrifuged to obtain a precipitate, which is washed with deionized water and ethanol, and then dried and ground to obtain a nickel-based Prussian blue battery positive electrode material.

[0007] Preferably, in the step one, the amount ratio of sodium citrate to nickel chloride solution is 4.4-8.8 g:25-50 mL, the concentration of nickel chloride solution is 0.1-0.2 mol / L, the concentration of sodium ferrocyanide solution is 0.1-0.2 mol / L, the amount ratio of polyvinylpyrrolidone to sodium chloride solution is 8 g:100-200 mL, and the concentration of sodium chloride solution is 0.25-0.5 mol / L.

[0008] Preferably, in the step two, the amount ratio of reagent A, reagent B and reagent C is 12.5-25 mL:25 mL:100 mL, the dropping time is 1-2 h, and the aging time of the suspension is 8-10 h.

[0009] Preferably, in the step three, the washing is performed for 3-5 times with deionized water and ethanol respectively, and the drying condition is vacuum drying at 70-80 ℃ for 24-36 h; the grinding is performed for 0.5-1 h by using a mortar.

[0010] Preferably, the nickel-based Prussian blue battery positive electrode material prepared in the step three is subjected to post-treatment modification, and the method is as follows: S31, dispersing the nickel-based Prussian blue battery positive electrode material powder into water, adding manganese chloride, adding potassium permanganate into the solution after the manganese chloride is completely dissolved, heating the solution in a water bath for a period of time, then performing suction filtration, and washing the obtained solid to obtain the treated nickel-based Prussian blue battery positive electrode material; S32, dispersing the treated nickel-based Prussian blue battery positive electrode material into water again, then adding trichloroacetic acid and pyrrole, stirring for a period of time, performing suction filtration, washing and drying to obtain the modified nickel-based Prussian blue battery positive electrode material.

[0011] Preferably, in the S31, the amount ratio of the nickel-based Prussian blue battery positive electrode material powder, manganese chloride, potassium permanganate and water is 10-20 g:2-2.5 g:1 g:100-150 mL.

[0012] Preferably, in the S31, the water bath heating temperature is 85-90 ℃, and the heating time is 1-2 h.

[0013] Preferably, in the S32, the amount ratio of the treated nickel-based Prussian blue battery positive electrode material, trichloroacetic acid, pyrrole and water is 10 g:0.01-0.02 mol:0.03-0.05 mol:100-200 mL, and the stirring time is 12-24 h.

[0014] A nickel-based Prussian blue battery positive electrode material is prepared by the above-mentioned method for preparing a nickel-based Prussian blue battery positive electrode material.

[0015] A battery, wherein the positive electrode material of the battery is the above-mentioned nickel-based Prussian blue battery positive electrode material.

[0016] The nickel-based Prussian blue battery positive electrode material prepared by the application has the characteristics of high capacity, low alternating current impedance and high long cycle stability, and has excellent electrochemical performance when used as a sodium ion battery positive electrode material. In addition, the nickel-based Prussian blue battery positive electrode material prepared by the application is modified. First, potassium permanganate is used to oxidize manganese chloride to generate Mn3O4 loaded on the surface of the nickel-based Prussian blue battery positive electrode material. Then, polypyrrole is coated on the nickel-based Prussian blue battery positive electrode material loaded with Mn3O4 in trichloroacetic acid, and trichloroacetic acid is used to remove the crystal water that may exist in the nickel-based Prussian blue battery positive electrode material during the reaction. The loaded Mn3O4 and the coated polypyrrole both have good conductivity, which can improve the conductivity of the nickel-based Prussian blue battery positive electrode material. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 SEM image of the material prepared in Example 1; Figure 2 SEM image of the material prepared in Example 2; Figure 3 SEM image of the material prepared in Comparative Example 1; Figure 4 SEM image of the material prepared in Comparative Example 2; Figure 5 XRD pattern of the material prepared in Example 1; Figure 6 CV diagram of the materials prepared in Examples 1-2 and Comparative Examples 1-2; Figure 7 Variation diagram of specific capacity of the materials prepared in Examples 1-2 and Comparative Examples 1-2 at different rates; Figure 8 Variation diagram of specific capacity of the materials prepared in Examples 3-5 and Example 1 at different rates; Figure 9 Charging and discharging curve diagram of the battery prepared by the material prepared in Example 1 under 2C cycle test; Figure 10 Charging and discharging curve diagram of the battery prepared by the material prepared in Example 2 under 2C cycle test; Figure 11 Long cycle test diagram of the battery prepared by the material prepared in Example 1 under 2C; Figure 12 Long cycle test diagram of the battery prepared by the material prepared in Example 2 under 2C. DETAILED DESCRIPTION

[0018] The application will be further described in detail below in combination with the embodiments and the drawings, so that those skilled in the art can implement it according to the description.

[0019] Example 1 A preparation method of a nickel-based Prussian blue battery positive electrode material, comprising the following steps: Step one, 8.8g of sodium citrate is dissolved into a 25mL nickel chloride solution with a concentration of 0.2mol / L to obtain reagent A, 0.02mol of sodium ferrocyanide is dissolved in 100mL of water to prepare a solution with a concentration of 0.2mol / L to obtain reagent B, and 8g of polyvinylpyrrolidone PVP (K30) is dissolved in 100mL of a sodium chloride solution with a concentration of 0.5mol / L to obtain reagent C; Step two, 25mL of reagent A and 25mL of reagent B are simultaneously and slowly added to 100mL of reagent C at room temperature, the dropping time is 1h, and reagent C is continuously stirred until reagent A and reagent B are completely added to reagent C, to obtain a suspension, and the obtained suspension is aged for 8h; Step three, the suspension after aging is centrifuged and separated, the obtained precipitate is washed with deionized water and ethanol for 3 times respectively, and then vacuum dried at 70℃ for 24h, the dried powder is fully ground in a mortar for 0.5h to obtain a nickel-based Prussian blue battery positive electrode material, which is recorded as NiHCF-3.2%.

[0020] Example 2 The difference between this example and example 1 is that the amount of sodium citrate in step one is 4.4g, and the other steps are consistent with example 1, to obtain a nickel-based Prussian blue battery positive electrode material, which is recorded as NiHCF-1.6%.

[0021] Example 3 The steps one to three of this example are consistent with example 1, and the difference is that the nickel-based Prussian blue battery positive electrode material prepared in step three is modified by post-treatment, and the method is: S31, 10g of nickel-based Prussian blue battery positive electrode material powder is dispersed into 100mL of water, 2g of manganese chloride is added, after the manganese chloride is completely dissolved, 1g of potassium permanganate is added to the solution, and the solution is heated in a water bath at 85℃ for 2h, and then filtered, and the obtained solid is washed to obtain a treated nickel-based Prussian blue battery positive electrode material; S32, 10g of the treated nickel-based Prussian blue battery positive electrode material is dispersed into 100mL of water again, and then 1.63g of trichloroacetic acid and 2.01g of pyrrole are added, and stirred for 12h, and then filtered, washed and dried to obtain a modified nickel-based Prussian blue battery positive electrode material, which is recorded as G-NiHCF-3.2%.

[0022] Example 4 The steps 1 to 3 of the present example are consistent with those of Example 1, except that the nickel-based Prussian blue battery positive electrode material prepared in step 3 is modified by post-treatment, and the method is as follows: S31, 10 g of the nickel-based Prussian blue battery positive electrode material powder is dispersed in 100 mL of water, and then 2 g of manganese chloride is added. After the manganese chloride is completely dissolved, 1 g of potassium permanganate is added to the solution, and the solution is heated in a water bath at 85°C for 2 h. Then, the obtained solid is washed by filtration to obtain the treated nickel-based Prussian blue battery positive electrode material, which is denoted as M-NiHCF-3.2%.

[0023] Example 5 The steps 1 to 3 of the present example are consistent with those of Example 1, except that the nickel-based Prussian blue battery positive electrode material prepared in step 3 is modified by post-treatment, and the method is as follows: S31, 10 g of the nickel-based Prussian blue battery positive electrode material powder is dispersed in 100 mL of water, and then 2 g of manganese chloride is added. After the manganese chloride is completely dissolved, 1 g of potassium permanganate is added to the solution, and the solution is heated in a water bath at 85°C for 2 h. Then, the obtained solid is washed by filtration to obtain the treated nickel-based Prussian blue battery positive electrode material, which is denoted as M-NiHCF-3.2%.

[0024] Comparative Example 1 Step 1, 8.8 g of sodium citrate is dissolved in 25 mL of 0.2 mol / L FeSO4 solution to obtain reagent A, 0.02 mol of sodium ferrocyanide is dissolved in 100 mL of water to obtain a 0.2 mol / L solution to obtain reagent B, and 8 g of polyvinylpyrrolidone PVP (K30) is dissolved in 100 mL of 0.5 mol / L sodium chloride solution to obtain reagent C; Step 2, 25 mL of reagent A and 25 mL of reagent B are simultaneously and slowly added to 100 mL of reagent C at room temperature, and the stirring of reagent C is continuously performed until reagent A and reagent B are completely added to reagent C, to obtain a suspension, and the obtained suspension is aged for 8 h; Step 3, the suspension after aging is centrifuged to obtain a precipitate, which is washed with deionized water and ethanol for 3 times, and then dried in a vacuum at 70°C for 24 h. The dried powder is ground in a mortar for 0.5 h to obtain the battery positive electrode material, which is denoted as NiHCF-Fe.

[0025] Comparative Example 2 The present comparative example is different from Example 1 in that, in step 1, the polyvinylpyrrolidone PVP (K30) is not added when preparing reagent C, and a 0.5 mol / L sodium chloride solution is directly used; other steps are consistent with those of Example 1, and the obtained battery positive electrode material is denoted as NiHCF-PVP-free.

[0026] The materials prepared in Examples 1-2 and Comparative Examples 1-2 were subjected to scanning electron microscopy, and the SEM images (with a scale length of 2 μm) are shown in FIGS. 1-4, respectively. Figures 1-4 Figure 1 FIG. 1 is an SEM image of the material prepared in Example 1, Figure 2 FIG. 2 is an SEM image of the material prepared in Example 2, Figure 3 FIG. 3 is an SEM image of the material prepared in Comparative Example 1, and Figure 4 FIG. 4 is an SEM image of the material prepared in Comparative Example 2. Figures 1-4 As can be seen from FIGS. 1-4, the surfaces of the NiHCF-3.2% and NiHCF-1.6% prepared in the Examples are rough and have a porous structure, which increases the specific surface area of the material and is beneficial to the surface reaction process; the NiHCF-Fe prepared in Comparative Example 1 has a relatively uniform size and exhibits a nearly cubic structure; and the particles of the NiHCF-PVP-free prepared in Comparative Example 2 are small and have a wide size distribution, which affects the reactivity and mass transfer process of the material.

[0027] Figure 5 FIG. 5 is an XRD pattern of the material prepared in Example 1; as can be seen, the diffraction peaks of the NiHCF-3.2% are split into two peaks with similar intensities at 24.5°, 34.5° and 47.8°, indicating that they are both rhombohedral structures, and the peaks at (200), (420), (440), (620) and other positions are split, changing from a single peak to a double peak. According to the splitting phenomenon, it is concluded that it is a rhombohedral phase, and the peaks at (111), (202), (404) and other positions are consistent with the standard, indicating that the NiHCF-3.2% material has the expected crystal structure characteristics; the (202) and (404) peaks have high intensities, indicating that the corresponding crystal faces are prominent in the NiHCF-3.2% material. According to the diffraction peak position and intensity, combined with the standard card, it can be determined that the main phase in the material is the target NiHCF-3.2% phase.

[0028] The nickel-based Prussian blue battery cathode material prepared in Example 1 was made into an electrode sheet, and the electrode sheet, an electrode shell, four drops of electrolyte and a 16 mm diameter glass were assembled into a CR2025 type button cell, and the battery was subjected to electrochemical performance testing; the electrode sheet was prepared by the following method: S1, 5 g of PVDF was dispersed in 95 g of NMP to prepare a 5 wt% PVDF solution as a binder; S2, 8 g of the nickel-based Prussian blue battery cathode material powder prepared in Example 1, 1 g of conductive carbon black (SuperP) and 1 g of the binder were mixed, NMP solvent was added dropwise to adjust the viscosity, and a slurry was obtained after stirring; ​S3. The slurry was coated on the cleaned aluminum foil with a coater, and the aluminum foil was dried at 120°C under vacuum for 12h. After drying, the aluminum foil was cut into a circular electrode sheet with a diameter of 14mm.

[0029] The positive electrode materials of the nickel-based Prussian blue batteries prepared in Examples 2-5 and the positive electrode material prepared in Comparative Example 1-2 were also made into electrode sheets and assembled into button batteries according to the above method, and electrochemical performance tests were carried out.

[0030] Figure 6 The CV curves of the materials prepared in Examples 1-2 and Comparative Example 1-2 are shown in the figure. It can be seen from the figure that the redox peaks of NiHCF-1.6% and NiHCF-3.2% are more obvious. The oxidation peak potential of NiHCF is 3.399 V, and the reduction peak potential is 3.045 V, and the difference between the two peak potentials is 354 mV. The oxidation peak potential of NiHCF-3.2% is 3.569 V, and the reduction peak potential is 3.29 V, and the difference between the two peak potentials is 278 mV. The peak potential difference of NiHCF-3.2% is obviously smaller than that of NiHCF-1.6%, indicating that the polarization degree of NiHCF-3.2% is small, and it has better kinetic performance. The area surrounded by the curve and the potential axis represents the charge transfer. Compared with NiHCF-1.6%, NiHCF-Fe and NiHCF-PVP-free materials, the area of NiHCF-3.2% is larger, indicating that more charge is transferred during the redox reaction in this potential range.

[0031] Figure 7 The figure shows the specific capacity change of the materials prepared in Examples 1-2 and Comparative Example 1-2 at different rates. It can be seen from the figure that the specific capacity values of the four materials gradually decrease when the rate increases from 0.1C to 3C. The specific capacity of NiHCF-PVP-free decreases from 23.22 mAh / g to 10.72 mAh / g, the specific capacity of NiHCF-Fe decreases from 28.60 mAh / g to 17.19 mAh / g, the specific capacity of NiHCF-1.6% decreases from 58.22 mAh / g to 32.72 mAh / g, and the specific capacity of NiHCF-3.2% decreases from 65.60 mAh / g to 36.19 mAh / g. At a low rate of 0.1C, NiHCF-1.6% and NiHCF-3.2% have relatively high specific capacities, but at a high rate of 3C, the specific capacity decreases significantly. This is because at a high rate, the polarization effect inside the battery is enhanced, and the ion diffusion and charge transfer process is limited. By comparing the specific capacities of the four materials at the same rate, it can be seen that the specific capacity of NiHCF-3.2% is the highest, indicating that the material NiHCF-3.2% has better electrochemical performance at the same rate.

[0032] Figure 8The specific capacity of the materials prepared in Examples 3-5 and Example 1 at different rates is shown in the graph. As can be seen from the graph, Example 3 is a post-treatment modification of the prepared nickel-based Prussian blue battery positive electrode material. First, manganese chloride is generated by potassium permanganate oxidation, and Mn304 is loaded on the surface of the nickel-based Prussian blue battery positive electrode material. Then, polypyrrole is coated on the nickel-based Prussian blue battery positive electrode material loaded with Mn304 in trichloroacetic acid, and trichloroacetic acid is used to remove the crystal water that may exist in the nickel-based Prussian blue battery positive electrode material during the reaction. The loaded Mn304 and the coated polypyrrole both have good conductivity, which can improve the conductivity of the nickel-based Prussian blue battery positive electrode material. When the rate increases from 0.1C to 3C, the specific capacity of G-NiHCF-3.2% decreases from 72.42 mAh / g to 41.21 mAh / g, and the specific capacity at different rates is improved. In Example 4, only Mn304 is loaded on the nickel-based Prussian blue to obtain M-NiHCF-3.2% material. When the rate increases from 0.1C to 3C, the specific capacity decreases from 68.34 mAh / g to 37.15 mAh / g. Although the specific capacity is also improved, it is not as good as Example 3. In Example 5, polypyrrole is coated on the nickel-based Prussian blue to obtain B-NiHCF-3.2% material. When the rate increases from 0.1C to 3C, the specific capacity decreases from 70.12 mAh / g to 38.28 mAh / g. Although the specific capacity is also improved, it is not as good as Example 3.

[0033] Figures 9-10 The charge-discharge curve of the battery prepared from the material prepared in Example 1 and Example 2 is tested at 2C (1C = 75 mAhg -1 ) under cyclic test; wherein Figure 9 corresponding to Example 1, Figure 10 corresponding to Example 2, the first discharge capacity of NiHCF-3.2% is 58.43 mAh / g, and the 30th discharge capacity is 51.66 mAh / g, so the capacity retention rate is 88.42%; the first discharge capacity of NiHCF-1.6% is 58.00 mAh / g, and the 30th discharge capacity is 50.01 mAh / g, so the capacity retention rate is 86.23%; it can be seen that the potential platform of NiHCF-3.2% is more stable and decays more slowly, indicating that the structure is more stable, and the cycle performance of NiHCF-3.2% is better, showing better cycle stability.

[0034] Figures 11-12 The long cycle test graph of the battery prepared from the material prepared in Example 1 and Example 2 is shown in the graph; wherein Figure 11 corresponding to Example 1, Figure 12Corresponding to Example 2, at 2C rate, the initial charge capacity of NiHCF-1.6% is higher than that of NiHCF-3.2%, indicating that NiHCF-1.6% has higher energy storage capacity at the initial stage, the capacity attenuation curve of NiHCF-3.2% material is relatively flat, and it performs more stable in long cycle, while the NiHCF-1.6% material has high initial capacity, but the attenuation amplitude is larger, and the stability is slightly poor; the attenuation of NiHCF-3.2% material is slower, and the stability is better, the specific capacity attenuation is slower and the efficiency is higher, and it performs better long cycle stability and higher efficiency at 2C rate.

[0035] While the embodiments of the application have been disclosed as above, it is not limited to the use listed in the specification and embodiments, and can be fully applied to various fields suitable for the application, and additional modifications can be easily realized by those skilled in the art, and therefore the application is not limited to specific details and the figures shown and described herein.

Claims

1. A method for preparing a nickel-based Prussian blue battery cathode material, characterized in that, The method comprises the following steps: Step one, dissolve sodium citrate into nickel chloride solution to obtain reagent A, dissolve sodium ferrocyanide in water to obtain reagent B, and dissolve polyvinylpyrrolidone in sodium chloride solution to obtain reagent C; Step two, reagent A and reagent B are simultaneously and slowly added into reagent C at room temperature, and reagent C is continuously stirred until reagent A and reagent B are completely added into reagent C, then a suspension is obtained, and the obtained suspension is aged; Step three, the suspension after aging is centrifugally separated, the obtained precipitate is washed with deionized water and ethanol, and then dried and ground to obtain a nickel-based Prussian blue battery positive electrode material.

2. The method for preparing the nickel-based Prussian blue battery cathode material as described in claim 1, characterized in that, In step one, the dosage ratio of sodium citrate to nickel chloride solution is 4.4-8.8 g:25-50 mL, the concentration of the nickel chloride solution is 0.1-0.2 mol / L, the concentration of the sodium ferrocyanide solution is 0.1-0.2 mol / L, the dosage ratio of polyvinylpyrrolidone to sodium chloride solution is 8 g:100-200 mL, and the concentration of the sodium chloride solution is 0.25-0.5 mol / L.

3. The method for preparing the nickel-based Prussian blue battery cathode material as described in claim 1, characterized in that, In step two, the dosage ratio of reagent A, reagent B and reagent C is 12.5-25 mL:25 mL:100 mL, the dropping time is 1-2 h, and the aging time of the suspension is 8-10 h.

4. The method for preparing the nickel-based Prussian blue battery cathode material as described in claim 1, characterized in that, In step three, the precipitate is washed with deionized water and ethanol for 3-5 times respectively, the drying condition is vacuum drying at 70-80 ℃ for 24-36 h, and the grinding time is 0.5-1 h.

5. The method for preparing the nickel-based Prussian blue battery cathode material as described in claim 1, characterized in that, The nickel-based Prussian blue battery positive electrode material prepared in step three is modified by the following method: S31, disperse the nickel-based Prussian blue battery positive electrode material powder into water, add manganese chloride, add potassium permanganate into the solution after the manganese chloride is completely dissolved, heat the solution in a water bath for a period of time, then filter, and wash the obtained solid to obtain a treated nickel-based Prussian blue battery positive electrode material; S32, disperse the treated nickel-based Prussian blue battery positive electrode material into water again, then add trichloroacetic acid and pyrrole, stir for a period of time, filter, wash and dry to obtain a modified nickel-based Prussian blue battery positive electrode material.

6. The method for preparing the nickel-based Prussian blue battery cathode material as described in claim 5, characterized in that, In S31, the dosage ratio of the nickel-based Prussian blue battery positive electrode material powder, manganese chloride, potassium permanganate and water is 10-20 g:2-2.5 g:1 g:100-150 mL.

7. The method for preparing the nickel-based Prussian blue battery cathode material as described in claim 5, characterized in that, In S31, the water bath heating temperature is 85-90 ℃, and the heating time is 1-2 h.

8. The method for preparing the nickel-based Prussian blue battery cathode material as described in claim 5, characterized in that, In S32, the dosage ratio of the treated nickel-based Prussian blue battery positive electrode material, trichloroacetic acid, pyrrole and water is 10 g:0.01-0.02 mol:0.03-0.05 mol:100-200 mL, and the stirring time is 12-24 h.

9. A nickel-based Prussian blue battery cathode material, characterized in that, The nickel-based Prussian blue battery positive electrode material is prepared by the method of any one of claims 1-5.

10. A battery, characterized by The positive electrode material of the battery is the nickel-based Prussian blue battery positive electrode material of claim 9.

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