JP2002260745A - Battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery which can warm up speedily and evenly the inside of a power-generating element 3 by heating a terminal block 9 or a connection can 15. SOLUTION: It is so constructed that a screw fastened resistor 10 or a metal- clad resistor 16 is fixed to a terminal block 9 connected and fixed to a terminal rod 5 protruding outside of a lid plate 2b of a battery case 2 of a nonaqueous electrolyte secondary battery 1 or a connection can 15 connected and fixed to the terminal block 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery such as a non-aqueous electrolyte secondary battery, whose output characteristics rapidly decrease as the temperature decreases.

[0002]

2. Description of the Related Art FIG. 7 shows an example of the configuration of a large non-aqueous electrolyte secondary battery 1 used for electric vehicles and the like. The non-aqueous electrolyte secondary battery 1 has four winding-type power generation elements 3 wound in a long cylindrical shape inside a rectangular box-shaped battery can 2 a of a metal battery case 2. . The positive and negative electrodes of each power generating element 3 are protruded from both end surfaces of the long cylindrical shape of the power generating element 3 by being wound while being shifted in opposite directions along the winding axis. Then, the positive and negative electrodes of each of the power generating elements 3 are sandwiched and connected by ultrasonic welding or the like to the concave portions of the current collecting connection plate 4 formed of a corrugated metal plate disposed at both ends of the four power generating elements 3. It is fixed. The current collecting connection plate 4 is connected to a metal terminal rod 5 fixedly connected to the upper end of the center.
The positive and negative terminals of the nonaqueous electrolyte secondary battery 1 are respectively connected. Therefore, the upper ends of these terminal rods 5
The battery can 2a protrudes to the outside through a cover plate 2b sealed at an upper end opening.

[0003]

However, when the temperature of the non-aqueous electrolyte secondary battery 1 falls, the output characteristics of the non-aqueous electrolyte secondary battery 1 suddenly decrease, and a large current cannot be discharged. For this reason, when the non-aqueous electrolyte secondary battery 1 is used in an electric vehicle, the starting performance deteriorates when the vehicle is driven on a cold winter morning where the temperature has dropped to below freezing point. Until the battery is warmed by heat generated by the motor or the driving of the motor, there has been a problem that high speed cannot be achieved.

In order to solve the above problem, a non-aqueous electrolyte secondary battery 1 is installed on a heater plate 6 as shown in FIG. A method of heating the nonaqueous electrolyte secondary battery 1 by winding a sheet-like heater material 7 around the side surface of the battery case 2 of the secondary battery 1 and energizing these heater plates 6 and the heater material 7 is also known. Proposed. However, since the heater plate 6 and the heater material 7 heat the nonaqueous electrolyte secondary battery 1 from the outside of the battery case 2, it takes a long time until the inside of the power generating element 3 housed through the insulating material warms. There is a problem that requires. In addition, since the power generating element 3 is formed by winding the positive and negative electrodes in multiple layers with the separator interposed therebetween, heat conduction in the radial direction of the winding deteriorates. For this reason, when the battery is heated from the outside of the battery case 2, the electrode arranged on the outer peripheral side of the power generating element 3 warms first, so that only the current density of the electrode on the outer peripheral side is increased and the deterioration is accelerated. There is also a problem that the life of the water electrolyte secondary battery 1 is shortened.

[0005] The above problem is not limited to the wound-type power generating element 3, but also occurs when a stacked-type power generating element is used.
In addition, not only the nonaqueous electrolyte secondary battery 1 but also other types of batteries such as lead-acid batteries generally have lower output characteristics as the temperature decreases, and in particular, the aqueous electrolyte may be frozen. Problems occur.

The present invention has been made in order to cope with such a situation, and an object of the present invention is to provide a battery capable of quickly and uniformly heating the inside of a power generating element by heating a terminal or a connection can. And

[0007]

The battery according to the present invention is characterized in that a heating element is attached to a terminal protruding outside the battery case or a connection can of the terminal.

According to the first aspect of the present invention, since the terminals and the connection can are heated by the heat generated by the heating element, the heat is smoothly applied to the electrodes of the power generating element directly or via a metal current collector. And the inside of the power generation element can be quickly and uniformly heated. Therefore, even when the outside air temperature is low, the output characteristics of the battery can be promptly improved, and there is no possibility that only a part of the electrode is deteriorated due to a variation in the temperature inside the power generation element.

[0009] The battery according to claim 2 is characterized in that the heating element generates heat by electric heating when power is supplied from the battery.

According to the second aspect of the present invention, since the heating element receives the power supply from the battery itself for heating, it is not necessary to prepare another battery for the heating element or to connect to an external power supply. . For example, in the case of a running electric car,
Since power cannot be supplied from outside, power is generally supplied from the battery itself to be heated.

The battery according to a third aspect is characterized in that the heating element generates heat by electric heating when power is supplied from the outside.

According to the third aspect of the present invention, since the heating element is supplied with power from the outside, not from the battery for heating, the heating element does not need to consider the power consumption of the battery itself. Warm will be able to do. For example, even in the case of an electric vehicle or the like, power can be externally supplied to the heating element when the vehicle is parked in the garage.

The battery according to a fourth aspect is characterized in that the heat generation of the heating element is controlled by a timer.

According to the fourth aspect of the present invention, the battery can be heated at the time designated by the timer or the battery can be heated at the designated time interval. , The starting characteristics can be improved from the beginning.

According to a fifth aspect of the present invention, there is provided a battery comprising: a temperature sensor for measuring the temperature of the battery or the environmental temperature of the battery; and a heating control device for controlling heat generation of the heating element based on the temperature measured by the temperature sensor. It is characterized by having.

Here, “battery temperature” means the surface temperature of the battery case or the internal temperature of the battery, and “battery environmental temperature” means the ambient temperature of the compartment or space in which the battery is installed. Means temperature.

According to the fifth aspect of the present invention, the battery is heated by heating the heating element only when the temperature actually decreases, so that the battery is heated when the outside air temperature is high or when the battery is discharged. There is no need to wastefully heat itself or the surroundings when it is getting warm. Further, the amount of heat generated by the heating element can be controlled depending on how much the temperature has dropped. Note that such heating control is performed only when the main switch is turned on by an operation, or combined with the control by the timer according to claim 4, so that heating is performed even when the battery is not used at all. The waste of heating can be eliminated.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 6 show an embodiment of the present invention. FIG. 1 is a perspective view of a non-aqueous electrolyte secondary battery in which a screw-fixed resistor is attached to a terminal block, and FIG. FIG. 3 is a circuit block diagram showing an example in which a photocoupler is used for a control circuit of a screw-fixed resistor attached to a terminal block of a water electrolyte secondary battery. FIG. 3 is a diagram showing a screw attached to a terminal block of a non-aqueous electrolyte secondary battery. FIG. 4 is a circuit block diagram showing an example in which a photo MOSFET is used as a control circuit of a fixed resistor. FIG. 4 is an example in which a relay is used in a control circuit of a screw fixed resistor attached to a terminal block of a nonaqueous electrolyte secondary battery. FIG. 5 is a circuit block diagram showing an example in which a transistor is used in a control circuit of a screw-fixed resistor attached to a terminal block of a non-aqueous electrolyte secondary battery, and FIG. 6 is a screw fixed to a connection can. Non-mounted type resistor It is a perspective view of the assembled battery electrolyte secondary battery. Components having the same functions as those of the conventional example shown in FIGS. 7 to 9 are denoted by the same reference numerals.

In this embodiment, a large non-aqueous electrolyte secondary battery 1 used for an electric vehicle or the like will be described as in the conventional example. As shown in FIG. 1, a battery case 2 of the non-aqueous electrolyte secondary battery 1 includes a battery can 2a and a lid plate 2b similar to those of the conventional example, and includes four power generating elements shown in FIG. 3 are stored. From both ends of the cover plate 2b, the upper ends of the terminal rods 5 connected to the positive and negative electrodes of these power generating elements 3 via the current collecting connection plate 4 respectively protrude. The upper ends of these terminal rods 5 protrude from the inside of the battery case 2 through through holes formed in the cover plate 2b, and are insulated and fixed between the terminal plates 5 and the cover plate 2b. The upper ends of the terminal rods 5 protruding above the cover plate 2b penetrate the terminal block 9 via the insulating plate 8, and are connected and fixed to the terminal block 9 by caulking. The terminal block 9 has a through-hole formed at one end of the metal plate to penetrate the upper end of the terminal rod 5 and caulked.
At the other end, a bolt 9a projecting upward is attached to a nut 9
The connection is fixed at b. The combination of the upper end of the terminal rod 5, the terminal block 9, the bolt 9a and the nut 9b is a terminal of the nonaqueous electrolyte secondary battery 1 protruding outside the battery case 2.

Screw-fixed resistors 10 are fixed to the metal plates of the positive and negative terminal blocks 9 by screws. The screw-fixed resistor 10 is a resistor that can flow a large current by attaching a screw to a heat sink and radiating heat. In this case, the resistor 10 is attached to the terminal block 9 in place of the heat sink to flow the current. It is used as a small heating element by electric heating. When the terminal block 9 is heated by the heat generated by the screw fixed type resistor 10, this heat is immediately transmitted to the electrodes of the power generating element 3 via the terminal rod 5 and the current collecting connecting plate 4. That is, the terminal block 9, the terminal rod 5, the current collecting connection plate 4, and the metal foil that is the current collecting base material of the electrode of the power generating element 3 are all made of a metal having good heat conductivity, and are used to reduce the electric resistance. Since they are connected and fixed to each other over a large area by caulking or welding, heat conduction between them is also performed smoothly. In order to increase the current collection efficiency, the electrodes of the power generation element 3 are formed by connecting the metal foils on the inner and outer circumferences of the winding together with the current collection connection plate 4.
And the heat transmitted to these metal foils can evenly warm the inside of the power generating element 3. On the other hand, when the nonaqueous electrolyte secondary battery 1 is heated from the outside of the battery case 2 as in the related art, heat conduction is hindered by the insulating material disposed between the battery case 2 and the power generation element 3. Not only that, even if the heat reaching the power generating element 3 is transmitted to the electrode at the outer peripheral portion of the winding, it takes a long time to reach the center portion because the separator is layered and overlapped. 3 cannot be heated evenly.

The screw-fixed resistor 10 is connected to a power supply 12 through a photocoupler 11, as shown in FIG. In the present embodiment, the non-aqueous electrolyte secondary battery 1 itself is used as the power supply 12. The photocoupler 11 is a switching element in which a light emitting diode and a phototransistor are combined, and turns on / off the energization of the screw-fixed resistor 10 from the power supply 12 by a control signal from the heating control circuit 13.
It switches off. However, a control element other than the photocoupler 11 can be used for controlling the energization of the screw-fixed resistor 10. As an example, the photo MOSFET 17 shown in FIG.
And a relay 18 that is mechanically turned on / off. Further, when it is not necessary to insulate the power supply 12 and the heating control circuit 13, it is possible to directly turn on / off using the transistor 19 as shown in FIG. Although not shown, the power supply of the heating control circuit 13 also uses the nonaqueous electrolyte secondary battery 1 here.

In the present embodiment, the heating control circuit 13 controls ON / OFF of energization to the screw-fixed resistor 10 according to the temperature detected by the thermistor 14. The thermistor 14, as shown in FIG.
By being attached to the outer surface of the screw-type resistor 10 without being affected by the heat generated by the screw-fixed resistor 10 as much as possible.
The temperature of the non-aqueous electrolyte secondary battery 1 is measured. That is, when the temperature of the nonaqueous electrolyte secondary battery 1 measured by the thermistor 14 is lower than a predetermined value, the heating control circuit 13 turns on the photocoupler 11 and The vessel 10 is energized to generate heat. When the non-aqueous electrolyte secondary battery 1 is heated by the heat generated by the screw fixed type resistor 10 and the temperature measured by the thermistor 14 exceeds a predetermined value, the photocoupler 11 is turned off.
The heat generation of the screw-fixed resistor 10 is stopped by setting it to FF.
Therefore, when the non-aqueous electrolyte secondary battery 1 is used in an electric vehicle, for example, when the ignition of the vehicle is turned on when the temperature drops below freezing, the heating control circuit 13 sends the non-aqueous electrolyte secondary battery 1 Is turned on, the temperature is measured by the thermistor 14, and since this temperature is equal to or lower than the predetermined value, the screw-fixed resistor 10 is energized to generate heat. For this reason, the non-aqueous electrolyte secondary battery 1
Since the temperature is raised at the same time as the ignition is turned on, the temperature immediately rises and returns to the original output characteristics, so that the starting performance can be improved. The heating control circuit 1
When the heating control is performed by the closed loop in this way, it is necessary to measure the temperature change inside the non-aqueous electrolyte secondary battery 1 as accurately as possible. Is more preferable. In addition, other temperature sensing elements such as a thermocouple can be used in place of the thermistor 14 for measuring the temperature.

According to the above configuration, when a main switch such as an ignition of an electric vehicle is turned on, if the temperature of the nonaqueous electrolyte secondary battery 1 at that time is low, the screw fixed type resistor 10 is energized. Since the inside of the power generating element 3 of the nonaqueous electrolyte secondary battery 1 can be quickly heated, it is possible to prevent the starting performance of the electric vehicle or the like from being deteriorated. In addition, since the power generating element 3 of the nonaqueous electrolyte secondary battery 1 is uniformly heated from the inside, there is no danger that only a part of the electrode is deteriorated due to temperature variation and the life is shortened.

In the above embodiment, the heating control circuit 13 is controlled so that the temperature of the non-aqueous electrolyte secondary battery 1 becomes higher than a predetermined temperature.
Has described the case where the heating control is performed by the closed loop, but the heating control by the open loop may be performed. Also in the case of the open loop heating control, when the temperature measured by the thermistor 14 is equal to or lower than a predetermined value, the screw-fixed resistor 10
However, regardless of the actual temperature rise of the non-aqueous electrolyte secondary battery 1, the current supply is stopped after a predetermined time has elapsed by the timer, or the ambient temperature around the non-aqueous electrolyte secondary battery 1 is changed. Can be stopped by being raised by driving a motor or the like. Therefore, in such open loop heating control, the thermistor 14
It is not always necessary to measure the temperature of the nonaqueous electrolyte secondary battery 1, and the ambient temperature around the nonaqueous electrolyte secondary battery 1 may be measured.

In the above embodiment, the heating control circuit 1
3 is a photocoupler for supplying current to the screw fixed type resistor 10.
Has been described, the amount of heat generated is controlled by controlling the amount of power supplied to the screw-fixed resistor 10 according to the temperature measured by the thermistor 14 or by changing the power supply time. Control may be performed stepwise or steplessly.

In the above embodiment, the heating control circuit 1
3 has described the case where the energization to the screw-fixed resistor 10 is controlled in accordance with the temperature measured by the thermistor 14, but regardless of the temperature, the energization to the screw-fixed resistor 10 is controlled by the time setting of the timer. It can also be controlled.
For example, in the case of a driver who commutes by electric vehicle, if a timer is set so that the screw fixed type resistor 10 is energized for a certain period of time just before commuting time during the winter season, the vehicle can be used for this vehicle. The nonaqueous electrolyte secondary battery 1 can be pre-warmed before boarding. When the timer is set so that the screw-fixed resistor 10 is energized at predetermined time intervals while the electric vehicle is stopped, the non-aqueous electrolyte secondary battery can be used even when the time of using the vehicle is undefined. 1 can be prevented from being too cold.

The thermistor 1 as in the above embodiment
The energization of the screw fixed type resistor 10 can be controlled by an operation without using the heating control circuit 4 or the heating control circuit 13. For example, in the case of an electric vehicle, the driver sets a switch for energizing the screw-fixed resistor 10 according to the temperature at that time before starting the vehicle or according to the operating state of the vehicle after starting. If it is manually turned on, the starting characteristics can be promptly improved. In this case, the energization switch of the screw-fixed resistor 10 may be manually turned off, or automatically turned off by a timer or the like.

In the above embodiment, the case where the power supply 12 of the screw-fixed resistor 10 is supplied from the non-aqueous electrolyte secondary battery 1 itself has been described. Power supply can also be used. When an external power supply is used, it is not necessary to consider the power consumption of the nonaqueous electrolyte secondary battery 1 due to heating.
Optimal heating control according to the application can be performed. For example, in the case of an electric vehicle, when the vehicle is parked in a garage, it is necessary to always control the heating so that the non-aqueous electrolyte secondary battery 1 does not drop below a predetermined temperature. Also, the starting characteristics can be maintained in a good state.

In the above embodiment, the case where the screw fixed type resistors 10 are attached to the respective terminal blocks 9 of the non-aqueous electrolyte secondary battery 1 has been described. In general, a plurality of nonaqueous electrolyte secondary batteries 1 are arranged side by side as shown in
A connection can 1 between the bolts 9a of the positive and negative terminal blocks 9
Since the wires are connected to each other by the connection at 5, the screw-fixed resistor 10 can also be attached to such a connection can 15. However, in FIG. 6, the metal clad resistor 1 is connected to the connection can 15 instead of the screw-fixed resistor 10.
6 is shown. Metal clad resistor 16
Is a resistor that allows a large current to flow by attaching a heat sink and radiating heat.
By attaching to the connection can 15 instead of the heat sink and passing an electric current, it is used as an electric heating element. Since the connection space of the connection can 15 is larger than that of the terminal block 9, the metal clad resistor 16 having a larger capacity and a larger size than the screw-fixed resistor 10 is used. Also in this case, the heat generated by the metal clad resistor 16 is quickly transmitted through the connection can 15 to the terminal blocks 9 at both ends.
Therefore, the inside of the non-aqueous electrolyte secondary battery 1 can be quickly and uniformly heated. However, even when the metal clad resistor 16 is attached to the connection can 15 in this manner, as shown in FIG. 6, the positive and negative terminal blocks 9 at both ends to which these connection cans 15 are not connected are screw-fixed resistances. It is preferable to attach a heating element such as the vessel 10. Further, a heating element such as a screw-fixed resistor 10 may be attached to the terminal block 9 to which the connection can 15 is connected.

In FIG. 6, the connection canister 15 is used, which is connected and fixed to the bolt 9a of the terminal block 9 serving as the terminal of the nonaqueous electrolyte secondary battery 1 with the nut 9b. Any connection can be used.
Further, the heating element such as the screw-fixed resistor 10 is not limited to the connection canister for connecting the terminals, but can be attached to a connection can such as a nut 9b for connecting and fixing the same.

In the above-described embodiment, the case where a resistor such as the screw-fixed resistor 10 or the metal clad resistor 16 is used as the heating element has been described. However, as a matter of course, the resistor is originally used as a heat source by electric heating. A heating element such as a heater can also be used. Further, a heating element that generates heat by means other than electric heating, a heating element that generates heat with energy other than electricity, or a heating element that generates heat by supplying a heated heat medium can also be used.

Further, in the above embodiment, the case where the terminal block 9 constituting the terminal of the non-aqueous electrolyte secondary battery 1 is connected to the electrode of the power generating element 3 via the terminal rod 5 and the current collecting connecting plate 4 will be described. However, the connection may be made via a lead material or the like, or the terminal may be directly connected to the electrode. further,
In the above embodiment, the non-aqueous electrolyte secondary battery 1 in which four wound power generating elements 3 are housed in the box-shaped battery case 2 has been described. However, in the present invention, the shape of the battery case 2 is not particularly limited. The number of the power generating elements 3 to be stored is not limited. Furthermore, this power generating element 3 is not limited to the wound type, and the same effect can be obtained by implementing the present invention because the situation in which heat is difficult to be transmitted in the electrode laminating direction is the same even in the case of a laminated type. Obtainable. Further, in the above-described embodiment, the non-aqueous electrolyte secondary battery 1 has been described. However, the present invention can be similarly applied to other types of batteries, such as a lead storage battery, whose output characteristics decrease as the temperature decreases.

[0034]

As is apparent from the above description, according to the battery of the present invention, the inside of the power generating element can be quickly and uniformly heated by the heat generated by the heating element attached to the terminal or the connection can. Even when the temperature is low, the output characteristics of the battery can be quickly improved. Further, since only a part of the inside of the power generating element is heated, there is no danger that a part of the electrode is deteriorated quickly and the life of the battery is shortened.

[Brief description of the drawings]

FIG. 1, showing an embodiment of the present invention, is a perspective view of a non-aqueous electrolyte secondary battery in which a screw-fixed resistor is attached to a terminal block.

FIG. 2 is a circuit block diagram illustrating an embodiment of the present invention, in which a photocoupler is used in a control circuit of a screw-fixed resistor attached to a terminal block of a nonaqueous electrolyte secondary battery. It is.

FIG. 3, showing an embodiment of the present invention, is a circuit block diagram illustrating an example in which a photo MOSFET is used as a control circuit of a screw-fixed resistor attached to a terminal block of a nonaqueous electrolyte secondary battery. It is.

FIG. 4 is a circuit block diagram showing one embodiment of the present invention and showing an example in which a relay is used in a control circuit of a screw-fixed resistor attached to a terminal block of a non-aqueous electrolyte secondary battery. is there.

FIG. 5 is a circuit block diagram illustrating an embodiment of the present invention, in which a transistor is used in a control circuit of a screw-fixed resistor attached to a terminal block of a nonaqueous electrolyte secondary battery. is there.

FIG. 6, showing one embodiment of the present invention, is a perspective view of a battery pack of a non-aqueous electrolyte secondary battery in which a screw-fixed resistor is attached to a connection can.

FIG. 7 is an exploded perspective view showing a conventional example and showing a structure of a non-aqueous electrolyte secondary battery.

FIG. 8 shows a conventional example, and is a perspective view of a nonaqueous electrolyte secondary battery installed on a heater plate.

FIG. 9 shows a conventional example, and is a perspective view of a non-aqueous electrolyte secondary battery in which a heater material is wound around a side surface.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Non-aqueous electrolyte secondary battery 2 Battery case 3 Power generation element 4 Current collection connection plate 5 Terminal rod 9 Terminal block 9a Bolt 9b Nut 10 Screw fixed resistor 13 Heating control circuit 14 Thermistor 15 Connection can 16 Metal clad resistor

Claims (5)

[Claims] 1. A battery, wherein a heating element is attached to a terminal or a connecting rod protruding outside the battery case. 2. The battery according to claim 1, wherein the heating element generates heat by electric heating when power is supplied from the battery. 3. The battery according to claim 1, wherein the heating element generates heat by electric heating when power is supplied from the outside. 4. The battery according to claim 1, wherein the heat generation of the heating element is controlled by a timer. 5. A temperature sensor for measuring a temperature of the battery or an environmental temperature of the battery, and a heating control device for controlling heat generation of the heating element based on the temperature measured by the temperature sensor. The battery according to claim 1, 2, 3, or 4.