JP2007141493A - Charging method for secondary battery and charging device thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a charging method and a charging device capable of improving charging and discharging cycle characteristics and reducing charging time in a secondary battery utilizing deposition and dissolution of Li in a negative electrode. <P>SOLUTION: In a current control charge process charging by controlling a charging current value, the charging current value is divided into five or more steps and increased in order and the quantity of charged electricity in each step is set 67.6% or less of the capacity of the secondary battery. The charging current value may be increased continuously. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a secondary battery charging method using precipitation and dissolution of a negative electrode active material, and a charging device used therefor.

  Conventionally, nickel-cadmium batteries, nickel-metal hydride batteries, lead batteries, and the like have been used as secondary batteries for electronic devices. However, in recent years, with the advancement of electronic technology, electronic devices have become more sophisticated, smaller, and more portable, and the demand for higher energy density of secondary batteries for electronic devices has increased. Therefore, as a secondary battery with a high discharge voltage, low self-discharge, and a long cycle life, a so-called lithium battery using a carbon material capable of occluding and releasing lithium ions for the negative electrode and a lithium cobalt composite oxide or the like for the positive electrode. Ion secondary batteries are being researched and developed.

  However, when a carbon material such as graphite is used for the negative electrode, there is a theoretical capacity of 372 mAh / g, and it is difficult to improve the energy density. Therefore, research and development of a so-called metal lithium secondary battery using metal lithium or a lithium alloy for the negative electrode and utilizing precipitation (dissolution) of lithium (Li) is underway. However, the metal lithium secondary battery has a problem that the charge / discharge cycle efficiency is low and the discharge capacity cannot be obtained when repeated charging is performed.

Therefore, it has been studied to improve the charge / discharge cycle efficiency by changing the charging method. For example, in Patent Document 1, the charging process is divided into a plurality of stages having different charging current values, the current value in the charging stage at the start of charging is relatively small, and the current value in each subsequent charging stage is charged. A charging method for making the current value larger than the current value is described. In Patent Literature 1, a coin-type secondary battery is used and the charging current value is changed in two stages, and the amount of charge at the start of charging is set to 17% to 80% of the battery capacity. Further, the charging current value at the start of charging is set to 0.4 mA (0.05 C) or less, and the charging current value thereafter is set to 2 to 5 times the charging current value at the start of charging.
International Publication No. WO00 / 42673 Pamphlet

  However, in the charging method described in Patent Document 1, for example, when a secondary battery having a charge / discharge capacity of 1000 mAh is charged at a constant current in two stages, the charge current value at the start of charging is 50 mA (0.05 C). Then, at least 3.4 hours are required for the charging time of the first stage, and even if the charging current value of the next stage is 250 mA, which is five times that at the start of charging, the charging time of the next stage is 3.3. I need time. That is, there is a problem that constant current charging requires about 6.7 hours at the minimum, and charging takes time.

  The present invention has been made in view of such problems, and its purpose is to improve the charge / discharge cycle characteristics of a secondary battery that uses precipitation and dissolution of the negative electrode active material in the negative electrode and to reduce the charging time. An object of the present invention is to provide a charging method and a charging device that can be shortened.

  A first secondary battery charging method according to the present invention is a method of charging a secondary battery using deposition and dissolution of a negative electrode active material in a negative electrode, and charging by controlling a charging current value. The current control charging process includes five or more stages having different charging current values, and the amount of charge in each stage is set to 67.6% or less of the battery capacity of the secondary battery. .

  A second secondary battery charging method according to the present invention charges a secondary battery that utilizes precipitation and dissolution of a negative electrode active material in a negative electrode, and controls the charging current value to perform charging. The current control charging process includes a process of continuously increasing the charging current value.

  A charging device for a first secondary battery according to the present invention charges a secondary battery using precipitation and dissolution of a negative electrode active material in a negative electrode, and controls a charging current value for the secondary battery. The current control charging unit controls the charging current so as to include five or more stages having different charging current values, and the amount of charge in each stage is determined by the secondary battery. It has a charging current control part which controls the amount of charge electricity so that it may become 67.6% or less of battery capacity.

  A charging device for a second secondary battery according to the present invention charges a secondary battery that uses precipitation and dissolution of a negative electrode active material in a negative electrode, and controls a charging current value for the secondary battery. The current control charging unit includes a charging current control unit that performs control so as to include a process in which the charging current value continuously increases.

  According to the charging method and the charging device of the secondary battery of the present invention, the charging electric quantity in each stage is set to 67.6% or less of the battery capacity of the secondary battery including five or more stages having different charging current values. Since the process includes a process of continuously increasing the charging current value, the charge / discharge cycle characteristics can be improved and the charging time can be shortened.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 shows an exploded configuration example of a secondary battery 10 suitable for using the charging method and the charging device according to the first embodiment of the present invention. The secondary battery 10 uses lithium as a negative electrode active material, and has a configuration in which a wound electrode body 10A is enclosed in a film-shaped exterior member 10B. A positive electrode lead 11 and a negative electrode lead 12 are attached to the wound electrode body 10A, and are led out of the exterior member 10B. The exterior member 10B is made of, for example, a laminate film in which an aluminum foil is sandwiched between synthetic resin films. In addition, although not shown in figure, the exterior member is not restricted to a film-like thing, You may be comprised by cans, such as cylindrical shape or square shape.

  FIG. 2 shows an enlarged part of the cross-sectional structure of the spirally wound electrode body 10A shown in FIG. The wound electrode body 10A is formed by laminating a positive electrode 13 and a negative electrode 14 via a separator 15 impregnated with an electrolytic solution and winding a plurality of times, and a protective tape 16 is wound around the outermost periphery. That is, a plurality of positive electrodes 13 and negative electrodes 14 are laminated from the winding center side toward the winding outer peripheral side. For example, the positive electrode 13 has a structure in which a positive electrode active material layer 13B is provided on both surfaces of a positive electrode current collector 13A. The positive electrode active material layer 13B includes, for example, a positive electrode material capable of inserting and extracting lithium as a positive electrode active material, and includes other materials such as a conductive material and a binder as necessary. May be. Examples of the positive electrode material capable of inserting and extracting lithium include lithium-containing compounds such as lithium oxide, lithium phosphorus oxide, and lithium sulfide. Specifically, lithium and at least one of cobalt (Co), nickel (Ni), manganese (Mn), iron (Fe), aluminum (Al), vanadium (V), and titanium (Ti) are used. The complex oxide containing or the phosphoric acid compound containing these is preferable.

  The negative electrode 14 has, for example, a configuration in which a negative electrode active material layer 14B is provided on both surfaces of a negative electrode current collector 14A. The negative electrode active material layer 14B is made of metallic lithium or a lithium alloy, and the metallic lithium is repeatedly deposited and dissolved by charging and discharging. Note that the negative electrode active material layer 14B is deposited and present only at the time of charging, and may not be dissolved and present at the time of discharging.

  The electrolytic solution contains, for example, a solvent and an electrolyte salt. Examples of the solvent include cyclic carbonates such as ethylene carbonate (1,3-dioxolan-2-one), propylene carbonate (4-methyl-1,3-dioxolan-2-one), butylene carbonate, or 4 -Fluoro-1,3-dioxolan-2-one, 4-trifluoromethyl-1,3-dioxolan-2-one, 4,4-difluoro-1,3-dioxolan-2-one, 4,5-difluoro -1,3-dioxolan-2-one, 4,4,5-trifluoro-1,3-dioxolan-2-one, 4,4,5,5-tetrafluoro-1,3-dioxolan-2-one Cyclic carbonate derivatives having halogen atoms such as 4-fluoromethyl-1,3-dioxolan-2-one or 4-difluoromethyl-1,3-dioxolan-2-one Or a chain carbonate such as dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, di (i-propyl) carbonate, di (n-propyl) carbonate, di (n-butyl) carbonate or di (tert-butyl) carbonate, Or a lactone such as γ-butyrolactone or γ-valerolactone, or a chain carboxylic acid ester such as methyl acetate, ethyl acetate, propyl acetate, methyl trimethyl acetate, ethyl trimethyl acetate, methyl propionate or ethyl propionate, or tetrahydrofuran, 2 -Rings such as methyltetrahydrofuran, tetrahydropyran, 1,3-dioxolane, 4-methyl-1,3-dioxolane, 1,3-dioxane, 4-methyl-1,3-dioxane or 1,3-benzodioxole Formula ether or 1,2-dimethoxy Chain ethers such as ethane, 1,2-diethoxyethane, diglyme, triglyme or diethyl ether, or sulfur compounds such as ethylene sulfite, propane sultone, propene sultone, sulfolane, methyl sulfolane or diethyl sulfine, or acetonitrile or propio Nitriles such as nitriles, chain carbamates such as methyl N, N-dimethylcarbamate, methyl N, N-diethylcarbamate, or 1,3-dioxol-2-one, 4,5-diphenyl-1 , 3-dioxol-2-one, 4-vinyl-1,3-dioxolan-2-one, carbonates having an unsaturated bond, such as allylmethyl carbonate or diallyl carbonate.

As the electrolyte salt, _{e.g., LiPF 6, LiBF 4, LiClO} 4, LiAsF 6, LiSbF 6, CF 3 SO 3 Li, (CF 3 SO 2) 3 CLi, LiCl, LiBr, LiI, LiPF 4 (CF 3) 2 LiPF ₃ (C ₂ F ₅ ) ₃ , LiPF ₃ (CF ₃ ) ₃ , LiPF ₃ (iso-C ₃ F ₇ ) ₃ , LiPF ₅ (iso-C ₃ F ₇ ), lithium bisoxalatoborate (LiB ( Examples thereof include lithium salts such as C ₂ O ₄ ) ₂ ), lithium oxalate difluoroborate, LiB (C ₆ H ₅ ) ₄ , LiN (CF ₃ SO ₂ ) _2, or LiN (C ₂ F ₅ SO ₂ ) ₂ .

  The separator 15 may be impregnated with the electrolytic solution as it is, or the electrolytic solution may be held in a polymer compound and used. Examples of the polymer compound include polymers and copolymers such as acrylonitrile, vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene, chlorotrifluoroethylene, ethylene oxide, and propylene oxide.

  FIG. 3 shows a schematic configuration of the charging device 20 according to the first embodiment of the present invention, and FIG. 4 shows a control state of the charging current value in the charging device 20. The charging device 20 controls, for example, a power supply circuit unit 21, a current control charging unit 22 that performs charging while controlling a charging current value for the secondary battery 10, and a charging voltage for the secondary battery 10. A voltage-controlled charging unit 23 that performs charging is provided. The power supply circuit unit 21 converts, for example, a power supply voltage supplied from the power supply 30 into a predetermined DC voltage, and supplies the voltage to the current control charging unit 22 or the voltage control charging unit 23 stably. An AC-DC converter is used.

  For example, as shown in FIG. 4, the current control charging unit 22 divides the secondary battery 10 into constant current charging from the charging start voltage to the charging end voltage in five or more n stages having different charging current values. For example, a charging current control unit 221, a timer 222, and a battery voltage detection unit 223 are provided. The charging current control unit 221 is connected to the power supply circuit unit 21, the timer 222, and the battery voltage detection unit 223, and controls the charging current value based on information from the timer 222 and the battery voltage detection unit 223. Yes. For example, the charging current control unit 221 sets a charging current value and a charging electricity amount at each stage, calculates a charging electricity amount at each stage based on information from the timer 222, and sets the charging electricity amount. When the value is reached, the next stage is entered. At that time, the amount of charged electricity at each stage is set within a range of 67.6% or less of the battery capacity of the secondary battery 10. Thereby, the charge / discharge cycle characteristics can be improved and the charging time by the current control charging unit 22 can be shortened to within 5.1 hours, for example.

  In addition, the charging current value is preferably set to be larger than the charging current value in the previous stage for at least a part of the second and subsequent stages in each stage, and the charging current value in each stage increases in order. It is more preferable if it is set to be. This is because a higher effect can be obtained. However, a stage where the charging current value is smaller than the previous stage may be inserted in part.

  Note that the charging current control unit 221 calculates a charging electricity amount based on information from the timer 222, and does not compare the calculated charging electricity amount with a set value, but the charging electricity amount at each stage is within the above range. Thus, the time is set based on the relationship with the charging current value, and when the time reaches the set value, the process may proceed to the next stage.

  The voltage control charging unit 23 performs constant voltage charging on the secondary battery 10, and includes a charging voltage control unit 231 and a current value detection unit 232. The charging voltage control unit 231 is connected to the power supply circuit unit 21, the battery voltage detection unit 223, and the current value detection unit 232, and determines the charging voltage value based on information from the battery voltage detection unit 223 and the current value detection unit 232. It comes to control. For example, in the charging voltage control unit 231, when the battery voltage detection unit 223 detects that the battery voltage has reached a predetermined charging end voltage, the charging voltage is controlled to the charging end voltage value and charging is started. When the current value detection unit 232 detects that the charging current value is equal to or lower than a predetermined end value, the charging is ended. The voltage control charging unit 23 may include a timer instead of the current value detection unit 232, and may end the charging when the charging time reaches a predetermined set value.

  FIG. 5 shows a method of charging the secondary battery 10 using the charging device 20 shown in FIG. First, the charging current control unit 221 controls the charging current value to the set value of the first stage, and performs the current control charging process of the first stage (step S101). Also, for example, the time is measured by the timer 222, and the charge electricity amount is calculated by the charge current control unit 221 based on the measured time. The charging current control unit 221, for example, when the calculated charge electricity amount reaches a set value of 67.6% or less of the battery capacity of the secondary battery 10 (step S102; Y, N), the first stage The current control charging process in the second stage is performed (step S103).

  Similarly to the first stage, the second-stage current-controlled charging process is also controlled until the set charging current value reaches the set value. Next, similarly, the current control charging process in which the charging current values are set separately in the third stage, the fourth stage, and the fifth stage or more is sequentially performed. In that case, it is preferable to set the charging current value of at least a part of the stage to be larger than the charging current value of the previous stage, and it is more preferable to set the charging current value of each stage to be sequentially larger. The last n-th stage current-controlled charging process set in this way is performed (step S104), and when the amount of charge reaches a set value (step S105; Y, N), a secondary is performed as necessary. When the battery voltage of the battery 10 is detected by the battery voltage detection unit 223 and the battery voltage has reached a predetermined charging end voltage value such as 4.2 V (step S106; Y, N), the charging current control unit 221 Terminate the control charging process.

  Subsequently, the charging voltage controller 231 controls the charging voltage to the charging end voltage value to perform a voltage controlled charging process (step S107). At this time, for example, when the charging current value is detected by the current value detection unit 232 and the charging current value becomes equal to or less than a predetermined end value (step S108; Y, N), the charging voltage control unit 231 performs the voltage controlled charging process. End.

  Although not shown in FIGS. 4 and 5, in addition to the above-described current-controlled charging process and voltage-controlled charging process, other charging processes may be performed, or discharging may be performed. In addition, as described above, in the current control charging process, the process proceeds to the next stage when the charging time reaches the set value, instead of proceeding to the next stage when the charge electricity amount reaches the set value. In the voltage-controlled charging process, charging is not terminated when the charging current value becomes equal to or lower than the end value, but charging is terminated when the charging time reaches the set value. Good.

  As described above, the present embodiment has a current control charging process including five or more stages having different charging current values, and the amount of charge in each stage is set to 67.6% or less of the battery capacity of the secondary battery 10. As a result, the charge / discharge cycle characteristics can be improved, and the current controlled charging process can be shortened to 5.1 hours or less.

  In particular, if the charging current value is set to be larger than the charging current value of the previous stage for at least a part of the second and subsequent stages of each stage, the charging current value of each stage is further increased in order. Therefore, a higher effect can be obtained.

(Second Embodiment)
FIG. 6 shows a schematic configuration of the charging device 40 according to the second embodiment of the present invention, and FIG. 7 shows a control state of the charging current value in the charging device 40. The charging device 40 is for charging the secondary battery 10 as in the first embodiment, for example, except that the configuration of the current control charging unit 42 is different from that of the first embodiment. It has the same configuration as the form. Therefore, in the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The current control charging unit 42 charges the secondary battery 10 from the charging start voltage to the charging end voltage while continuously increasing the charging current value as shown in FIG. 7, for example. For example, a charging current control unit 421 and a battery voltage detection unit 223 similar to the first embodiment are provided. The charging current control unit 421 is connected to the power supply circuit unit 21 and the battery voltage detection unit 223, and the charging current is detected until the battery voltage detection unit 223 detects that the battery voltage has reached a predetermined charging end voltage. Charging is performed by controlling the value. Thereby, the charge / discharge cycle characteristics can be improved, and the charging time by the current control charging unit 22 can be shortened to within 5.1 hours, for example. The charging current value may be changed linearly as shown in FIG. 7, for example, but may be changed in a curved line.

  FIG. 8 shows a method of charging the secondary battery 10 using the charging device 40 shown in FIG. First, the charging current control unit 421 performs a current control charging process while continuously increasing the charging current value (step S201). At that time, the battery voltage of the secondary battery 10 is detected by the battery voltage detection unit 223, and when the battery voltage reaches a predetermined charging end voltage value such as 4.2V (step S202; Y, N), the charging current The controller 421 ends the current control charging process. Next, in the same manner as in the first embodiment, the voltage control charging process is performed by the charging voltage control unit 231 (step S203), and the voltage control charging process is terminated when the charging current value becomes equal to or less than a predetermined end value. (Step S204; Y, N).

  Also in this embodiment, in addition to the current controlled charging process and the voltage controlled charging process, other charging processes may be performed, or discharging may be performed. Moreover, you may combine with the electric current control charging process demonstrated in 1st Embodiment. In other words, a part of the current control charging process may include a process of continuously increasing the charging current value.

  As described above, in the present embodiment, the process of continuously increasing the charging current value is provided, so that the charge / discharge cycle characteristics can be improved and the current control charging process is shortened to within 5.1 hours. can do.

  Further, specific embodiments of the present invention will be described in detail.

(Examples 1-17)
The secondary battery 10 shown in FIGS. First, lithium cobalt composite oxide (LiCoO ₂ ) is used as a positive electrode active material, 91% by weight of a mixture of 95% by weight of this lithium cobalt composite oxide powder and 5% by weight of lithium carbonate powder, and flaky graphite as a conductive material. 6% by mass and 3 parts by mass of polyvinylidene fluoride as a binder were mixed and then dispersed in N-methyl-2-pyrrolidone to obtain a slurry. Next, this slurry was uniformly applied to both surfaces of a positive electrode current collector 13A made of an aluminum foil having a thickness of 12 μm, dried, and compression molded to form a positive electrode active material layer 13B, whereby a positive electrode 13 was produced. Subsequently, the positive electrode lead 11 made of aluminum was welded to the positive electrode current collector 13A.

  Further, a negative electrode active material layer 14B was formed by pressing a metal lithium foil having a thickness of 30 μm on both surfaces of a negative electrode current collector 14A made of a copper foil having a thickness of 8 μm, and the negative electrode 14 was produced. Next, the negative electrode lead 12 made of nickel was welded to the negative electrode current collector 12A.

After that, the produced positive electrode 13 and negative electrode 14 are laminated through a separator 15 made of a microporous polyethylene film, wound many times, and the outermost periphery is fixed with a protective tape 16 to produce a wound electrode body 10A. did. Next, the wound electrode body 10A is sandwiched between exterior members 10B made of an aluminum laminate film, and the outer edge except for one side is heat-sealed to form a bag, and then the electrolyte is injected, and the remaining one side is heat-fused. Wear and seal. The electrolyte solution was prepared by dissolving LiPF ₆ at a concentration of 1 mol / l in a solvent in which 4-fluoro-1,3-dioxolan-2-one and dimethyl carbonate were mixed at a mass ratio of 1: 1. Using. Thereby, the secondary battery 10 having a charging capacity of 1000 mAh was obtained.

  Next, with respect to the produced secondary battery 10, a charge / discharge cycle test is performed by changing the charging conditions in an environment of 23 ° C., and the number of cycles until the discharge capacity becomes 70% or less of the discharge capacity of the first cycle is investigated. It was. Charging is performed until the battery voltage reaches 4.2 V, and then the voltage control charging process is performed until the current value reaches 1.5 mA. The discharging is performed at a constant current of 165 mA and the battery voltage is 3. This was done until 0V was reached.

  At that time, in Examples 1 to 10, the current-controlled charging process was divided into 10 stages, and the charging current value, the charging time, and the charge electricity amount at each stage were changed as shown in Table 1. In Examples 11 to 14, the current-controlled charging process was divided into five stages, and the charging current value, the charging time, and the charge electricity amount at each stage were changed as shown in Table 2. In Examples 15 and 16, the current-controlled charging process was divided into 30 stages, and the charging current value, the charging time, and the amount of charged electricity at each stage were changed as shown in Table 2. In Example 17, the current control charging process was performed while continuously increasing the charging current value. In each of Examples 1 to 17, the current control charging process was set to be within 5.1 hours. In each of Examples 1 to 16, the charging current value at each stage was increased in order, and the amount of charge at each stage was set to 67.6% or less of the battery capacity of the secondary battery 10.

  As Comparative Examples 1 to 8 with respect to Examples 1 to 17, except that the conditions of the current control charging process were changed as shown in Table 3, other than that, the discharge capacity was 1 cycle. The number of cycles until 70% or less of the eye discharge capacity was examined. In Comparative Example 1, the current control charging process is one stage, and the charging current value is set so that the current control charging process is 5 hours. In Comparative Example 2, the current control charging process is set to two stages, the charging current value is set so that the current control charging process is 5 hours, and the amount of charge in the second stage is set to be larger than 67.6% of the battery capacity. Is. In Comparative Examples 3 and 4, the current control charging process has two stages, the amount of charge in each stage is 67.6% or less of the battery capacity, and the current control charging process exceeds 5.1 hours. In Comparative Example 5, the current control charging process is set to two stages, the amount of charge in each stage is set to 67.6% or less of the battery capacity, and the current control charging process is set to 5 hours. In Comparative Examples 6 to 8, the current control charging process is set to 10 steps, 5 steps, or 30 steps, the charging current value is set so that the current control charging process is 5 hours, and the amount of charge in the last step is set to the battery capacity. It is larger than 67.6%.

  Table 4 summarizes the conditions of the current control charging process and the results of the number of charge / discharge cycles in Examples 1 to 17 and Comparative Examples 1 to 8.

  As shown in Table 4, Examples 1 to 16 were divided into 5 or more stages with different charging current values, and the amount of charge at each stage was 67.6% or less of the battery capacity, and the charging current values were continuously According to Example 17, which was greatly increased, the number of charge / discharge cycles could be improved to 150 times or more. On the other hand, in Comparative Example 1 in which the current-controlled charging process is one stage, and Comparative Examples 2, 5 to 8 in which each stage has a charge electricity amount exceeding 67.6% of the battery capacity, Only the number of charge / discharge cycles of 125 times or less was obtained. In addition, in Comparative Examples 3 and 4 in which the current control charging process is divided into two stages and the amount of charge at each stage is 67.6% or less of the battery capacity, the current control charging process exceeds 5.1 hours, It took a long time to charge. Further, the current-controlled charging process is divided into two stages, the amount of charge in each stage is 67.6% or less of the battery capacity, and the charging current value in the first stage is made larger than those in Comparative Examples 3 and 4, thereby charging time. In Comparative Example 5 in which the length was shortened, the number of charge / discharge cycles was as small as 121 times.

  That is, if the current-controlled charging process is divided into five or more stages having different charging current values, and the amount of charge in each stage is 67.6% or less of the battery capacity, or the charging current value is continuous in the current-controlled charging process. It was found that the charging / discharging cycle characteristics can be improved and the current-controlled charging process can be shortened to 5.1 hours or less by making it larger.

  Although the present invention has been described with reference to the embodiments and examples, the present invention is not limited to the embodiments and examples, and various modifications can be made. For example, in the above-described embodiments and examples, the case where an electrolytic solution is used as the electrolyte is described. In the above-described embodiment, the case where a gel electrolyte in which the electrolytic solution is held in a polymer compound is used is also described. Other electrolytes may be used. Other electrolytes include, for example, a mixture of an ion conductive inorganic compound such as ion conductive ceramics, ion conductive glass or ionic crystal and an electrolytic solution, or a mixture of another inorganic compound and an electrolytic solution. Or a mixture of these inorganic compounds and a gel electrolyte.

  Moreover, although the said embodiment and Example demonstrated the case where 10 A of winding electrode bodies which laminated | stacked and wound the positive electrode 13 and the negative electrode 14 were provided, the electrode body which laminated | stacked a pair of positive electrode and negative electrode is provided. The present invention can be similarly applied to the case where the electrode body including a plurality of positive electrodes and negative electrodes is provided. Furthermore, in the above-described embodiments and examples, the case where the film-like exterior member 10B is used has been described. However, the present invention can be similarly applied to a case where a can is used as the exterior member, and the shape is also cylindrical. Any shape such as a square shape, a coin shape, a button shape or a sheet shape may be used.

  In addition, in the above embodiments and examples, a battery using lithium as a negative electrode active material has been described. However, other alkali metals such as sodium (Na) or potassium (K), magnesium or calcium (Ca), or the like are used. The present invention can also be applied to the case of using an alkaline earth metal or another light metal such as aluminum.

It is a partial exploded perspective view showing the structure of the secondary battery using the charging method and charging device which concern on embodiment of this invention. It is sectional drawing along the II line of the winding electrode body in the secondary battery shown in FIG. It is a schematic block diagram of the charging device which concerns on the 1st Embodiment of this invention. It is a figure showing the control state of the charging current value in the charging device shown in FIG. It is a flowchart showing the charging method which concerns on the 1st Embodiment of this invention. It is a schematic block diagram of the charging device which concerns on the 2nd Embodiment of this invention. It is a figure showing the control state of the charging current value in the charging device shown in FIG. It is a flowchart showing the charge method which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Secondary battery, 10A ... Winding electrode body, 10B ... Exterior member, 11 ... Positive electrode lead, 12 ... Negative electrode lead, 13 ... Positive electrode, 13A ... Positive electrode collector, 13B ... Positive electrode active material layer, 14 ... Negative electrode, DESCRIPTION OF SYMBOLS 14A ... Negative electrode collector, 14B ... Negative electrode active material layer, 15 ... Separator, 16 ... Protection tape, 20, 40 ... Charging device, 21 ... Power supply circuit part, 22, 42 ... Current control charging part, 221, 421 ... Charging Current control unit, 222 ... timer, 223 ... battery voltage detection unit, 23 ... voltage control charging unit, 231 ... charging voltage control unit, 232 ... current value detection unit.

Claims (16)

A method for charging a secondary battery using precipitation and dissolution of a negative electrode active material in a negative electrode,
It has a current control charging process that controls charging current value to perform charging,
The current-controlled charging process includes five or more stages with different charging current values, and the amount of charge in each stage is 67.6% or less of the battery capacity of the secondary battery. How to charge the battery. The charging method of the secondary battery according to claim 1, wherein the charging current value is set to be larger than the charging current value of the previous stage for at least a part of the second and subsequent stages. The charging method of the secondary battery according to claim 1, wherein the charging current value at each stage is increased in order. The method of charging a secondary battery according to claim 1, wherein a time of the current control charging process is within 5.1 hours. The method for charging a secondary battery according to claim 1, wherein the negative electrode active material is lithium. A method for charging a secondary battery using precipitation and dissolution of a negative electrode active material in a negative electrode,
It has a current control charging process that controls charging current value to perform charging,
The current control charging process includes a process of continuously increasing a charging current value. The method of charging a secondary battery according to claim 6, wherein a time of the current control charging process is within 5.1 hours. The method for charging a secondary battery according to claim 6, wherein the negative electrode active material is lithium. A charging device for a secondary battery that utilizes precipitation and dissolution of a negative electrode active material in a negative electrode,
For the secondary battery, comprising a current control charging unit that performs charging by controlling the charging current value,
The current control charging unit controls the charging current so as to include five or more stages having different charging current values, and the amount of charge in each stage is 67.6% or less of the battery capacity of the secondary battery. A charging device for a secondary battery, comprising: a charging current control unit that controls the amount of charged electricity. The charging of the secondary battery according to claim 9, wherein the charging current control unit controls the charging current value to be larger than the charging current value of the previous stage for at least a part of the second stage and thereafter. apparatus. The charging device for a secondary battery according to claim 9, wherein the charging current control unit controls the charging current value at each stage to increase in order. The charging device for a secondary battery according to claim 9, wherein a time for charging performed by the current control charging unit is within 5.1 hours. The secondary battery charging device according to claim 9, wherein the negative electrode active material is lithium. A charging device for a secondary battery that utilizes precipitation and dissolution of a negative electrode active material in a negative electrode,
For the secondary battery, comprising a current control charging unit that performs charging by controlling the charging current value,
The current control charging unit includes a charging current control unit that performs control so as to include a process in which a charging current value is continuously increased. The charging device for a secondary battery according to claim 14, wherein a time for charging performed by the current control charging unit is within 5.1 hours. The secondary battery charging device according to claim 14, wherein the negative electrode active material is lithium.

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