JP4215538B2 - Secondary battery - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a secondary battery having a signal terminal for outputting battery information.
[0002]
[Prior art]
Secondary batteries have the property that the temperature rises abruptly when charged and discharged with a large current. For example, when the battery is charged, if the temperature becomes abnormally high, the battery performance may be reduced. In order to prevent the battery temperature from becoming abnormally high during charging, a charger for charging while detecting the battery temperature with a temperature sensor such as a thermistor has been developed. When the battery temperature becomes higher than the set temperature, the charger cuts off the charging current to prevent the battery temperature from rising. A charger that rapidly charges a battery with a large current has a strong tendency to increase the temperature of the battery during charging. Therefore, the battery is charged while detecting the battery temperature. However, the method of detecting the temperature of the battery with the temperature sensor provided in the charger is difficult to quickly detect the temperature rise of the battery. This is because there is a gap between the temperature sensor and the battery to be charged, or a plastic case is interposed.
[0003]
A secondary battery that eliminates this drawback is described in Japanese Patent Application Laid-Open No. 2005-26830. The secondary battery of this publication has a PTC fixed to the bottom surface. The PTC is connected in series with the bottom electrode. In this secondary battery, since the PTC is always connected in series, when the battery temperature rises or an excessive current flows, the resistance of the PTC increases rapidly and the current of the battery is substantially cut off.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-340192
[Problems to be solved by the invention]
The secondary battery in which the PTC is connected to the battery can cut off an excessive current and can be safely used because the current can be cut off at a high temperature. However, in the secondary battery having this structure, when the PTC is laminated on the bottom surface of the standard battery, the positive and negative electrode intervals are increased. For this reason, for example, if PTCs are stacked on the bottom surface of an AA battery and connected in series, the AA battery charger cannot be charged. In order to be able to charge with an AA charger, it is necessary to shorten the battery corresponding to the thickness of the stacked PTC. However, if the battery is shortened, the charge capacity is reduced.
[0006]
Furthermore, since the secondary battery in which the PTCs are connected in series charges the secondary battery via the PTC, it is difficult to accurately detect only the battery temperature because the PTC is heated by the charging current. . In particular, if the charging current is increased in order to shorten the charging time, the heat generation of the PTC increases and the battery temperature cannot be accurately detected. Further, when PTCs are connected in series and charged, it becomes difficult to accurately detect the battery voltage. This is because the voltage drop of the PTC derails the battery voltage. For this reason, it is difficult to accurately detect full charge in the method of detecting battery voltage and detecting full charge.
[0007]
The present invention has been developed for the purpose of solving such drawbacks. An important object of the present invention is to provide a secondary battery that can accurately detect information such as battery temperature without reducing the charge capacity.
[0008]
[Means for Solving the Problems]
In the secondary battery of the present invention, the opening of the outer can 1 is closed with the sealing plate 4, and the convex electrode 2 that is one of the positive and negative electrodes is provided on the sealing plate 4, and the other electrode is also used as the outer can 1. The battery 10 includes an insulating plate 6 disposed on the sealing plate 4 and around the outside of the convex electrode 2, and a signal terminal 5 fixed to the insulating plate 6. The signal terminal 5 is electrically insulated from the convex electrode 2, is electrically connected to the other electrode, and outputs battery information from the signal terminal 5. Around the outer periphery of the convex electrode 2, the signal terminal 5 is arranged in the range of the protruding width of the protruding portion of the protruding electrode 2 in the protruding direction.
[0009]
The signal terminal 5 can be connected to a protection element 7. The protective element 7 can be a thermistor or a PTC. The signal terminal 5 and the insulating plate 6 may be formed in a ring shape having through holes 5A and 14 through which the convex electrode 2 is inserted. Further, the signal terminal 5 can be disposed at a position lower than the protruding surface of the convex electrode 2. Furthermore, the signal terminal 5 can be fixed to the battery 10 with a heat shrink film.
The signal terminal 5 is connected to an IC chip or a resistor. Around the outside of the convex electrode 2, the protective element 7, the IC chip, or the resistor is disposed in the range of the protruding width of the protruding portion of the convex electrode 2 in the protruding direction.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. However, the following examples illustrate secondary batteries for embodying the technical idea of the present invention, and the present invention does not specify secondary batteries as the following.
[0011]
Further, in this specification, in order to facilitate understanding of the scope of claims, the numbers corresponding to the members shown in the examples are referred to as “the scope of claims” and “the means for solving the problems”. It is added to the member shown by. However, the members shown in the claims are not limited to the members in the embodiments.
[0012]
In the secondary battery shown in FIGS. 1 and 2, an electrode (not shown) and an electrolytic solution (not shown) are put in an outer can 1 and hermetically closed. The electrode is formed by laminating a positive electrode and a negative electrode via a separator, and one of the positive electrode and the negative electrode is connected to the convex electrode 2 and the other is connected to the outer can 1. The secondary battery is a rechargeable battery such as a nickel-hydrogen battery, a nickel-cadmium battery, or a lithium ion battery. The external shape of the secondary battery is AA size. However, the outer shape of the secondary battery can be a single size, a single size, a single size, or other shapes.
[0013]
In the illustrated secondary battery, the convex electrode 2 is provided on the sealing plate 4. Therefore, the battery end surface 3 provided with the convex electrode 2 is used as the sealing plate 4. The sealing plate 4 is a metal plate and has the same polarity as the convex electrode.
[0014]
In the secondary battery, the signal terminal 5 is fixed to the battery end surface 3 on which the convex electrode 2 is provided. The signal terminal 5 is a metal plate, and has a through hole 5A through which the convex electrode 2 penetrates in an insulated state. The signal terminal 5 is disposed in a ring shape around the convex electrode 2 by inserting the convex electrode 2 through the through hole 5 </ b> A. The signal terminal 5 is disposed on the battery end surface 3 via the insulating plate 6. That is, the insulating plate 6 is disposed between the signal terminal 5 and the battery end surface 3 to insulate the signal terminal 5 from the battery end surface 3.
[0015]
In the illustrated secondary battery, the signal terminal 5 is connected to the electrode of the battery 10 via the protective element 7. The protective element 7 has a first terminal that is one terminal connected to the electrode of the battery 10 and a second terminal that is the other terminal connected to the signal terminal 5. The protective element 7 is a temperature sensor such as a thermistor or PTC. A secondary battery in which the protection element 7 is used as a temperature sensor and connected to the signal terminal 5 can detect the battery temperature at the signal terminal 5. FIG. 3 shows a circuit diagram of a secondary battery in which the protective element 7 is connected in series with the electrode of the battery 10. As shown in the circuit diagram, the secondary battery can be charged while the signal terminal 5 is connected to the input terminal of the charger and the temperature of the secondary battery is detected by the charger. The charger detects the battery temperature from the electrical resistance between the input terminal connected to the signal terminal 5 and one of the electrodes, and controls the charging current based on the detected battery temperature. This structure can be charged while accurately detecting the battery temperature with a temperature sensor fixed directly to the battery 10.
[0016]
However, the secondary battery of the present invention does not necessarily connect the protective element 7 such as a temperature sensor to the signal terminal 5. This is because the signal terminal 5 can be used not only as a battery temperature but also as a terminal for determining the authenticity of the battery 10. The signal terminal 5 is used not only for battery temperature and authentication, but also for outputting battery information. The secondary battery that determines the authenticity of the battery 10 connects a resistor between the signal terminal 5 and the electrode of the battery 10. A charger for charging the secondary battery or an electric device to which the secondary battery is attached determines the authenticity of the battery 10 based on the electric resistance between the signal terminal 5 and the electrode. Further, instead of the resistor, an IC chip that stores battery information may be connected, and the authenticity may be determined by reading the signal of the IC chip.
[0017]
In the secondary battery shown in the figure, a sealing plate 4 having a convex electrode 2 is airtightly fixed to an opening of an outer can 1 with a caulking structure. A packing 8 is sandwiched between the sealing plate 4 and the outer can 1. The packing 8 hermetically closes the space between the sealing plate 4 and the outer can 1, and insulates the sealing plate 4 from the outer can 1. This secondary battery has caulking ridges 9 having a caulking structure around the battery end surface 3. In the illustrated secondary battery, an insulating plate 6 is disposed on a crimping ridge 9. In the secondary battery of FIG. 2, the insulating plate 6 is fixed on the crimping ridge 9, and the protective element 7 is disposed in a recess formed between the crimping ridge 9 and the projection electrode 2. In this structure, the protective element 7 can be arranged by effectively using the concave portion formed around the convex electrode 2. However, the insulating plate can be disposed not on the upper surface of the crimping ridge but on the inside of the crimping ridge.
[0018]
The insulating plate 6 is bonded and fixed to the battery end surface 3. However, the insulating plate 6 can be fixed to the battery end surface 3 via the lead 11 of the protective element 7 and further fixed with the outer skin 12 covering the surface of the secondary battery. The outer skin 12 is a cylindrical heat shrink film, and a secondary battery can be inserted and heat shrunk to fix the insulating plate 6 to the secondary battery. The secondary battery in which the insulating plate 6 is bonded and fixed can also more reliably fix the insulating plate 6 with the outer skin 12. As shown in FIGS. 1 and 2, the outer skin 12 covers the outer can 1 so as to cover a part of the outer periphery of the insulating plate 6 and fixes the insulating plate 6. The secondary battery shown in the figure also covers the outer periphery of the signal terminal 5 with the outer skin 12. This structure can also prevent the signal terminal 5 from being separated from the insulating plate 6 by the outer skin 12.
[0019]
In the secondary battery of FIG. 1, the insulating plate 6 is used as a spacer 13 formed by molding plastic. The spacer 13 which is the insulating plate 6 fixes the signal terminal 5 on the upper surface. The spacer 13 as the insulating plate 6 is formed to be slightly smaller than the outer shape of the battery end surface 3 so as to be substantially equal to the outer shape of the battery end surface 3 with the convex electrode 2 and not to protrude from the battery end surface 3. The spacer 13 which is the insulating plate 6 is provided with a through hole 14 through which the convex electrode 2 is inserted, and the convex electrode 2 is inserted into the through hole 14. Furthermore, the spacer 13 which is the insulating plate 6 in the figure is provided with a peripheral wall 15 protruding upward around the through hole 14 in an integrated manner. A ring-shaped signal terminal 5 is fixed to the outside of the peripheral wall 15. In other words, the peripheral wall 15 of the spacer 13 that is the insulating plate 6 is fitted into the through hole 14 of the ring-shaped signal terminal 5. This structure has an advantage that the signal terminal 5 and the convex electrode 2 are insulated in an ideal state, and the signal terminal 5 can be fixed in a fixed position.
[0020]
As shown in the exploded perspective view of FIG. 4, the spacer 13 which is the insulating plate 6 is provided with a notched portion 16 formed on a part of the outer periphery or cut away, and the protective element 7 is provided here. ing. The spacer 13 which is the insulating plate 6 is provided with a notch 16 so as to penetrate vertically, and the protective element 7 is disposed here. The protective element 7 has an upper surface connected to the signal terminal 5 and a lead 11 connected to the lower surface. The lead 11 is connected to the side surface of the outer can 1 which is one electrode of the battery 10 by a method such as welding. The spacer 13 which is the insulating plate 6 shown in FIG. 4 is provided with an outer peripheral wall 17 integrally formed on the outer periphery. The spacer 13 can be fixed so as not to be displaced by inserting the spacer 13 between the outer peripheral wall 17 and the peripheral wall 15.
[0021]
The secondary battery of FIG. 2 uses the insulating plate 6 as a circuit board 18. The circuit board 18 which is the insulating plate 6 has the signal terminal 5 bonded and fixed to the surface. The circuit board 18 which is the insulating plate 6 is an insulating substrate such as a glass epoxy resin substrate reinforced with glass fibers. As shown in the exploded perspective view of FIG. 5, the circuit board 18 that is the insulating plate 6 is provided with a through hole 14 through which the convex electrode 2 is inserted, and the convex electrode 2 is inserted into the through hole 14. The ring-shaped signal terminal 5 has an inner shape larger than the outer shape of the convex electrode 2 so as not to contact the convex electrode 2. That is, a gap is provided between the convex electrode 2 and the signal terminal 5.
[0022]
The circuit board 18 which is the insulating plate 6 has the protective element 7 fixed to the back surface. The protective element 7 is disposed inside the caulking ridge 9 and in a concave portion formed between the caulking ridge 9 and the convex electrode 2. In order to insulate the protective element 7 disposed here from the sealing plate 4, an insulating sheet 19 is disposed between the protective plate 7 and the sealing plate 4. The upper surface of the protection element 7 is connected to the signal terminal 5 fixed to the upper surface of the circuit board 18 that is the insulating plate 6, and the lead 11 is connected to the lower surface of the protection element 7. The upper surface of the protection element 7 is connected to the signal terminal 5 through a through hole (not shown) provided in the circuit board 18. The lead 11 is fixed to the side surface of the outer can 1 by welding.
[0023]
【The invention's effect】
The secondary battery of the present invention has an advantage that information such as battery temperature can be accurately detected without reducing the charging capacity. The secondary battery of the present invention includes an insulating plate arranged around the convex electrode and a signal terminal 5 fixed to the insulating plate, and electrically insulates the signal terminal from the convex electrode. This is because the battery information is output from the signal terminal by being electrically connected to the other electrode. This secondary battery can output battery information such as battery temperature from a signal terminal connected to the electrode of the battery. Therefore, the battery can be charged while accurately detecting the battery temperature when rapidly charging with a large current.
[0024]
In particular, since the secondary battery of the present invention can have the same overall length as a conventional battery without a signal terminal without reducing the battery capacity, it is compatible with the equipment used.
[0025]
Further, the signal terminal provided on the battery end face is a dedicated terminal from which the secondary battery is not charged or discharged. For this reason, there is also a feature that the battery voltage can be accurately detected while rapidly charging with a large current and the full charge can be accurately detected.
[Brief description of the drawings]
FIG. 1 is an enlarged cross-sectional view of a convex electrode side of a secondary battery according to one embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view of a secondary battery according to another embodiment of the present invention on the convex electrode side. 3 is a circuit diagram of a secondary battery according to an embodiment of the present invention. FIG. 4 is an exploded perspective view of a signal terminal, an insulating plate, a protection element, and a lead of the secondary battery shown in FIG. Exploded perspective view of signal terminals, insulating plate, protection element and lead of secondary battery shown
DESCRIPTION OF SYMBOLS 1 ... Exterior can 2 ... Convex part electrode 3 ... Battery end surface 4 ... Sealing plate 5 ... Signal terminal 5A ... Through-hole 6 ... Insulating plate 7 ... Protection element 8 ... Packing 9 ... Caulking protrusion 10 ... Battery 11 ... Lead 12 ... Outer skin DESCRIPTION OF SYMBOLS 13 ... Spacer 14 ... Through-hole 15 ... Perimeter wall 16 ... Notch part 17 ... Outer peripheral wall 18 ... Circuit board 19 ... Insulation sheet

Claims (4)

The opening of the outer can (1) is closed with the sealing plate (4), and the convex electrode (2), which is one of the positive and negative electrodes, is provided on the sealing plate (4), and the other electrode is attached to the outer can (1). Combined battery (10), insulating plate (6) disposed on the outer periphery of the convex electrode (2) on the sealing plate (4), and a signal terminal fixed to the insulating plate (6) ( 5), the signal terminal (5) is electrically insulated from the convex electrode (2) and electrically connected to the other electrode so that battery information is output from the signal terminal (5). And
Around the outside of the convex electrode (2), the signal terminal (5) is arranged in the range of the protruding width in the protruding direction at the protruding portion of the convex electrode (2),
The signal terminal (5) is connected to an element that is one of a protective element, a resistor, and an IC chip, and the protective element (7) is a thermistor or a PTC,
Further, the outer periphery of the protruding electrode (2), the range of the width that protrudes in the protruding direction of the protruding portion of the protruding electrode (2), the element is either of the protective device (7) resistor and the IC chip Secondary battery arranged .   The signal terminal (5) and the insulating plate (6) are formed in a ring shape having through holes (5A) and (14) through which the convex electrode (2) is inserted, respectively. Secondary battery.   The secondary battery according to claim 1, wherein the signal terminal (5) is disposed at a position lower than a protruding surface of the convex electrode (2).   The secondary battery according to claim 1, wherein the signal terminal (5) is fixed to the battery (10) with a heat shrink film.

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