JP2016177941A - Battery state detection device, electronic apparatus, and method for detecting battery state - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a battery state detection device detecting a battery state to safely use a battery; an electronic apparatus; and a method for detecting a battery state.SOLUTION: A battery state detection device includes: sensors 11, 12 in contact with a battery 20 to detect a shape change of a surface of the battery 20; and a determination circuit 111 performing arithmetic processing of outputs of the sensors 11, 12 and measuring a state of a shape change of a surface of the battery 20 and an internal resistance of the battery 20 to determine a battery state.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a battery state detection device for a battery, an electronic device including the battery state detection device, and a battery state detection method.

Generally, battery abnormalities include battery swelling. This swelling is caused by the generation of gas or the like due to deterioration inside the battery.
In addition, since the conventional battery package is made hard, it has been generally recognized that the above-mentioned battery swelling has occurred in the battery.
In Patent Document 1, a strain sensor is attached to the surface of a film outer casing in which a power generation element including a positive electrode and a negative electrode is housed in an internal sealed chamber, and the internal pressure of the film outer casing is accurately detected. Is disclosed.

JP 2000-340264 A

However, in the technique disclosed in Patent Document 1, it is impossible to determine whether the output of the sensor is changed due to swelling due to an abnormality in the internal state of the battery, or whether the output is changed due to bending, twisting, or the like of the battery package. It has been proposed to stop charging and discharging the battery when it is detected that the battery has increased.
On the other hand, in recent years, development of a battery having a flexible package has been promoted in order to cope with various uses of the battery. For example, a film laminate is used for the battery package to cope with the deformation. If the battery package is deformed within an allowable range, even when the battery is deformed, if the battery is normal, charging and discharging can be performed in the deformed state. In such a flexible battery, when the stop function in Patent Document 1 is provided, there is a problem in that charge / discharge is stopped even if the battery can be normally charged / discharged.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a battery state detection device, an electronic device, and a battery state for detecting the state of the battery in order to use the battery safely. It is to provide a detection method.

In order to solve the above-described problems and achieve the object of the present invention, the present invention is configured as follows.
That is, the battery state detection device according to the present invention includes a sensor that contacts a battery package and detects a change in shape of the surface of the battery package, a battery internal resistance measurement circuit that measures the internal resistance of the battery, and the sensor. A determination circuit that determines a state of the battery based on a change in shape of the battery and an internal resistance of the battery by the battery internal resistance measurement circuit.
Other means will be described in the embodiment for carrying out the invention.

  ADVANTAGE OF THE INVENTION According to this invention, in order to use a battery safely, the battery state detection apparatus, electronic device, and battery state detection method which detect the state of a battery can be provided.

(A) is a figure which shows the state which attached the battery state detection apparatus which concerns on 1st Embodiment of this invention, and the sensor with which this battery state detection apparatus is equipped to the battery. (B) is a figure which shows the state which the local swelling produced in the battery. (A) is a figure which shows the state which has received the deformation | transformation by bending. (B) is a figure which shows both the state in which the battery produced the local swelling, and the state which has received the deformation | transformation by the state bending which has flexibility. It is a flowchart which detects abnormality of the flexible battery of the battery state detection apparatus which concerns on 1st Embodiment of this invention, and determines whether it is normal. It is a figure which shows an example of an internal resistance measurement circuit. It is a figure which shows the equivalent circuit of a battery. It is a characteristic view which shows the relationship of the voltage, electric current, and internal resistance of a battery. It is a figure which shows the structural example of the battery built-in apparatus which concerns on 2nd Embodiment of this invention. It is a figure which shows the process of bonding the sensor of the battery built-in apparatus which concerns on 2nd Embodiment of this invention, and a battery, and a relationship. (A) is a figure which shows a mode at the time of receiving a bending pressure in the state which the sensor and battery of the battery built-in apparatus which concern on 2nd Embodiment of this invention bonded together. (B) is a figure which shows the mode at the time of receiving pulling force. (C) is a figure which shows a mode when the force of twist is added.

  Hereinafter, modes for carrying out the present invention (hereinafter referred to as “embodiments”) will be described with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof will be omitted as appropriate.

«First embodiment: battery state detection device»
The battery state detection device according to the first embodiment of the present invention, the sensors included in the battery state detection device, various battery states, and a battery state detection flowchart will be described in order.
In the following description, the description will mainly be made as a “battery state detection device”, but it also serves as a “battery state detection method”.

<Battery state detection device>
FIGS. 1A and 1B are views showing a state in which a battery state detection device according to a first embodiment of the present invention and a sensor included in the battery state detection device are attached to a battery.
In FIG. 1A, a battery state detection device 100 according to the first embodiment of the present invention detects a deformation of the surface of a package of a battery 20 as, for example, a change in pressure (pressure sensor, shape change detection means). 11 and 12 and a detection block 101 for detecting a change in the output of the sensors 11 and 12.

The sensor 11 is placed in contact with one (upper surface) of the surface of the battery 20 package. Further, the sensor 12 is placed in contact with the other surface (lower surface) of the surface of the battery 20. The sensor 11 and the sensor 12 are independent from each other and are two sensors.
In order for the sensors 11 and 12 to detect deformation of the surface of the battery 20 package, it is desirable that the surfaces of the sensors 11 and 12 and the surface of the battery 20 package be in close contact with each other. However, the sensors 11 and 12 and the battery 20 are not necessarily fixed or bonded. For example, you may make it contact with the battery 20 closely using the elasticity of the sensors 11 and 12.
Further, a sensor output signal line 15 for transmitting the output of the sensor 11 and a sensor output signal line 16 for transmitting the output of the sensor 12 are connected to the detection block 101, respectively.

  The battery 20 has flexibility (flexibility). Further, the two power lines 21 and 22 (+, GND: FIG. 4) of the power source of the battery 20 are connected to the detection block 101. The battery 20 is preferably a secondary battery such as a lithium ion battery, but is not limited thereto.

The detection block 101 includes a determination circuit 111 that is a CPU (Central Processing Unit). The detection block 101 is comprehensively processed by the determination circuit 111.
The determination circuit 111 includes a core (CPU core) 121 and a peripheral (peripheral device, input device) 122.
The peripheral 122 includes a sensor output calculation determination circuit (shape change determination means) 131 and a battery internal resistance measurement circuit (battery internal resistance measurement means) 132.

The sensor output change of the sensors 11 and 12 is detected by the sensor output calculation determination circuit 131 of the determination circuit 111.
Further, the change in the battery internal resistance of the battery 20 is detected by the battery internal resistance measurement circuit 132 of the determination circuit 111.
The operations of the sensor output calculation determination circuit 131 and the battery internal resistance measurement circuit 132 are executed by calculation processing in the determination circuit 111.

  In FIG. 1A, the battery 20 does not swell in a normal state. Therefore, the sensors 11 and 12 are also in the normal value range, and no abnormal value is detected.

<Various sensor and battery status>
Next, various states of the sensor and the battery will be described. As described above, FIG. 1A shows a state where the battery does not bulge locally and the battery as a whole is not deformed.

<When the battery expands>
FIG. 1B is a diagram showing a state in which a local bulge (201) has occurred in the battery 20. As described above, this local swelling (201) is caused by the generation of gas or the like in the battery 20 due to the deterioration of the battery or the like.
As shown in FIG. 1B, when one surface of the package of the battery 20 provided with the sensor 11 transitions from a normal state to a state where a local bulge (201) occurs, the output of the sensor 11 is Change. The change in the output of the sensor 11 is input to the determination circuit 111 via the sensor output signal line 15. If the amount of change in the output of the sensor 11 is equal to or greater than a first threshold described later, the sensor output calculation determination circuit 131 of the determination circuit 111 determines that there is a possibility that an abnormality has occurred in the battery 20. If the change amount of the output of the sensor 11 is an expansion that is less than the first threshold value, the process proceeds to step S54 described later. The process proceeds to step S53. Thereafter, after step S53, the battery internal resistance measurement circuit 132 measures the internal resistance value of the battery 20 in step S56, and in step S57, the determination circuit 111 determines that the internal resistance value of the battery 20 is abnormal. In other words, if the determination circuit 111 determines that the internal resistance value of the battery 20 is abnormal in step S57, it means that the possibility that the battery 20 is abnormal has expanded to some extent.
If the battery has expanded, before it becomes equal to or greater than the second threshold value greater than the first threshold value, it is determined that the internal resistance value of the battery 20 is an abnormal value in step S57 described later, and the process proceeds to step S58. Therefore, the expansion does not reach the second threshold value or more.
The expansion of the battery due to the generation of gas inside is not necessarily limited to the local expansion as shown in FIG. 1B, and the entire package of the battery 20 may expand.

<When the battery is deformed by external stress>
FIG. 2A is a diagram illustrating a state in which the battery 20 is deformed by stress from the outside.
In FIG. 2A, the sensors 11 and 12 both detect deformation and output it to the sensor output calculation determination circuit 131 of the determination circuit 111.
Output signals of the sensors 11 and 12 are input to the determination circuit 111 via the sensor output signal lines 15 and 16. If the amount of change in the output of any one of the sensors 11 and 12 is less than the first threshold value, no abnormality will occur immediately. Therefore, the process proceeds to step S54, and the change in the output from the sensors 11 and 12 occurs. If the amount is about the first threshold value or more, the process proceeds to step S53 described later. Thereafter, after step S53, the battery internal resistance measurement circuit 132 measures the internal resistance value of the battery 20 in step S56. If the determination circuit 111 determines that the internal resistance value of the battery 20 is not abnormal in step S57, the battery 20 This means that the battery 20 has been deformed by external stress to such an extent that there is no possibility of causing an abnormality.
If the amount of change in the output of the sensors 11 and 12 is about the second threshold value or more in step S53, it is considered that the possibility that the battery 20 will be abnormally generated due to external stress is bent to some extent, and the process proceeds to step S58. To do.
Note that the battery internal resistance slightly increases due to deformation, and the battery internal resistance measurement circuit 132 of the determination circuit 111 may detect a slight change.

<< When battery deformation and local expansion of the battery occur simultaneously due to external stress >>
FIG. 2B is a diagram showing both the state in which the battery 20 is locally swollen (202) and the state in which the battery 20 is deformed by stress from the outside.
In the state shown in FIG. 2B, changes in the outputs of the sensors 11 and 12 are input to the determination circuit 111 via the sensor output signal lines 15 and 16. If the amount of change in the output of any of the sensors 11 and 12 is greater than or equal to the second threshold, the sensor output calculation determination circuit 131 of the determination circuit 111 determines that there is an abnormality, and the process proceeds to step S58.
Even if both of the output variations of the sensors 11 and 12 are less than the second threshold, if the state is equal to or greater than the first threshold described later, the process proceeds to step S56.
If the amount of change in the output of the sensors 11 and 12 is less than the first threshold value, no abnormality will occur immediately, and the process proceeds to step S54.

<Battery state detection flowchart>
Next, sensors 11 and 12 (shape change detection means) for detecting a change in shape of the surface of the battery 20, a sensor output calculation determination circuit 131 (shape change determination means) for calculating and determining the outputs of the sensors 11 and 12, A flow for detecting the state of a flexible battery by the battery internal resistance measurement circuit 132 (battery internal resistance measurement means) and the determination circuit 111 that controls these will be described.
FIG. 3 is a flowchart for detecting abnormality of the flexible battery 20 and determining whether it is normal.

<< Step S51 >>
In FIG. 3, a flow for determining whether or not the flexible battery is normal (abnormal) is started from step (process) S51 expressed as “preliminary setting”.
The battery state detection device 100 determines various determination values based on the characteristics of the sensors 11 and 12 and various parameters of the battery 20 during normal use (internal resistance, temperature, current, voltage, load current) at the start of “preliminary setting”. Acquire the appropriate voltage drop etc.) in advance and set it. Specifically, sensor output data in an initial state in which the sensors 11 and 12 are not deformed is stored in the storage circuit of the detection block 101. If it is unknown whether the sensors 11 and 12 are in an initial state where they are not deformed, the sensor output data in the initial state when assembled as the battery state detection device 100 may be stored in the storage circuit. Good.
Further, the internal resistance value under each condition (battery remaining value, that is, the state of charge, temperature, load current) is acquired and accumulated as data.
That is, at this “preliminary setting” stage (step, process), the remaining battery level, the internal resistance value at each remaining battery level, the reference value of the sensor output, and the “first” used in the determination in step S52 described later. ”Threshold”, “second threshold” used in the determination in step S53, and a range determined as abnormal compared to the initial internal resistance value of the battery 20 used in the determination in step S57, that is, “third threshold”. Keep it.
When the “preliminary setting” in step S51 ends, the process proceeds to step S52.

<< Step S52 >>
In step S52, the sensor output calculation determination circuit 131 of the determination circuit 111 receives the deformation of the output data output from the sensors 11 and 12 at a predetermined timing and the sensors 11 and 12 stored in the storage circuit of the detection block 101. The sensor output data in the initial state that is not yet compared are compared, and the sensor output change amount that is the difference is obtained.
Then, it is determined whether or not the sensor output change amount is greater than or equal to the “first threshold” serving as a first reference for determining the abnormality of the sensors 11 and 12 prepared in the “preliminary setting” in step S51. The circuit 131 compares and determines. Although the sensor output change amount and the first threshold value are compared twice, the sensor output data and the first threshold value in the initial state not subjected to the deformation are set in advance. When the threshold value of 1 is a positive value, | (output data value output from measured sensor) − (initial sensor output data) | ≧ (first threshold value), (output from measured sensor) Output data value) ≧ (first threshold) + (initial sensor output data) = m, (measured output data value output from sensor) ≦ − (first threshold) − (initial If m and n of n are obtained in advance and stored, it is possible to determine the transition to the step of further verifying the presence or absence of abnormality by one comparison.
If the sensor output change amount (sensor output change amount) is greater than or equal to the first threshold (YES), the process proceeds to step S53.
When the sensor output change amount is less than the first threshold (NO), the process proceeds to step S54.
In step S52, it is determined whether the deformation of the battery package is relatively large or slight based on the sensor output change amount. If it is relatively large, the process proceeds to step S53, and if it is slight, the process proceeds to step S54.

<< Step S53 >>
In step S53, the sensor output change amount measured in step S52 bulges stored in the memory circuit in the “preliminary setting” in step S51, and a serious abnormality that may cause battery destruction due to deformation due to external stress is detected. The sensor output calculation determination circuit 131 determines whether or not the output change of the sensor to be determined is larger than the “second threshold”. Note that from | (output data value output from measured sensor) − (sensor output data in initial state) | ≧ (second threshold), (output data value output from measured sensor) ≧ (Second threshold) + (sensor output data in the initial state) = M, (output data value output from the measured sensor) ≦ − (second threshold) − (sensor output data in the initial state) If M and N of = N are obtained in advance and stored, the transition to the next step can be determined by a single comparison.
If the sensor output change amount is greater than or equal to the second threshold (YES), the process proceeds to step S58.
If the sensor output change amount is less than the second threshold (NO), the process proceeds to step S56.
Steps S58 and S56 will be described later.
In this step S53, if the sensor output change amount, that is, the deformation of the battery 20 package is large and there is a possibility of battery destruction, the process immediately proceeds to step S58 of the battery protection operation, and the deformation of the battery 20 package is performed. If it cannot be determined that there is a possibility of battery destruction uniquely from the amount, but it cannot be determined whether there is a possibility of battery destruction inside, the process proceeds to step S56 of measuring the internal resistance of the battery.

<< Step S54 >>
Step S54, which is advanced when the answer is (NO) in step S52, will be described.
In step S54, “multiple times of sensor output measurement and calculation of average value of sensor outputs” are performed.
That is, in step S54, the sensor output calculation determination circuit 131 of the determination circuit 111 calculates the average value of the output detected multiple times at different timings by the sensor 11 and the average value of the output detected multiple times at different timings by the sensor 12. The process proceeds to step S55.
In this step S54, although the sensor output change amount in step S52 is less than the first threshold value, there is a possibility that an erroneous output change amount due to the detection error of the sensors 11 and 12 may occur. A more reliable sensor output change amount is obtained by repeating and averaging.

<< Step S55 >>
In step S55, the sensor output change amount in step S52 continues to be less than the first threshold value, but time is measured to confirm at a predetermined interval an abnormality that cannot be detected by deformation.
If the output change time of the sensors 11 and 12 is less than the set value (NO) in step S55, the process returns to step S52, and the output change time reaches the set value as long as the sensor output change amount is less than the first threshold. Steps S52, S54, and S55 are repeated until.
If it is determined in step S55 that the output change time of the sensors 11 and 12 is longer than the set value (YES), the process proceeds to step S56.

<< Step S56 >>
Step S56 is a “battery internal resistance measurement” step.
In the case of (NO) in step S53, the battery 20 does not show any abnormal shape change to some extent, but the battery internal resistance measurement circuit 132 measures (measures) whether there is any abnormality in the internal resistance of the battery 20 or not. To do.
In the case of (YES) in step S55, there is a possibility that the battery 20 may be abnormal due to expansion. Therefore, in step S56, the battery internal resistance measurement circuit 132 measures (measures) the internal resistance of the battery 20.
Then, the process proceeds to step S57.
The internal resistance measuring circuit and the internal resistance measuring method of the battery 20 will be described later.

<< Step S57 >>
In step S57, the determination circuit 111 compares whether or not the internal resistance value measured in step S56 is an abnormally high value compared to the initial internal resistance value that should be taken if normal. Whether or not it is abnormally high is determined based on the “third threshold value” prepared in the “preliminary setting” in step S51.
If the internal resistance value measured in step S56 is an abnormally high value (YES), the process proceeds to step S58.
Moreover, when the value compared with the internal resistance value measured in step S56 is small, the battery 20 is deformed by an external stress. However, since the battery 20 is flexible, the internal resistance value is an abnormal value. Since the battery 20 can be used continuously since it is not shown, it is determined that there is no abnormality, the process returns to step S52, and the above flow is repeated.
Here, since the internal resistance of the battery 20 varies depending on the storage amount (storage state) of the battery 20, temperature, load current, and the like, the storage amount of the battery 20 set in the “preliminary setting” in step S51, Compare the initial internal resistance value (determination value, threshold value) under the same conditions as much as possible, such as temperature and load current.
Instead of the above, step S57 compares the internal resistance value measured in step S56 with the initial internal resistance upper limit value that should be taken if it is normal, taking into account the “third threshold value” and the initial internal resistance value. If the initial internal resistance upper limit value is exceeded (YES), the process proceeds to step S58. If the initial internal resistance upper limit value is not more than (NO), the process may return to step S52.

<< Step S58 >>
Step S58 is a step of performing "alert, charging prohibition, battery protection operation" on the assumption that the battery 20 is abnormal.
In the case of (YES) in step S53 and in the case of (YES) in step S57, the process proceeds to step S58. That is, the process proceeds to step S58 when it is determined that the battery 20 may be abnormal.
In step S58, assuming that there is an abnormality in battery 20, the following is performed.
<1>"Alert"
Assuming that there is an abnormality in the battery, an alert signal for the use of the battery is transmitted to a load that supplies power, or an alert sound is emitted to a user who uses this load.
<2> `` No charging ''
Charging is prohibited because there is an abnormality in the battery.
<3> Battery protection operation
For example, an operation in which a large current flows is prohibited in addition to the above-described “alert” and “charge prohibition” treatments, assuming that the battery is abnormal.
Although “alert”, “charge prohibition”, and “battery protection operation” are described, these countermeasures are collectively described as “battery protection operation” as appropriate.
In step S58, the supply of power to the load is stopped after a certain period of time after "alert, charging prohibition, battery protection operation". Based on the alert, the load stores the data of the application in use in the memory before shutting down the power supply of the battery 20 and then shuts down the application.

In addition, this flowchart is a flowchart which considered that the battery which has flexibility receives a deformation | transformation in the range which does not have a trouble. That is, it is an example of a flowchart in a battery state without urgency in terms of battery protection. If the urgency of battery protection or product protection is more important, other flows can be taken.
In this flowchart, step S54 and step S55 are described separately, but these may be collectively regarded as one step. Similarly, step S56 and step S57 are described separately, but these may be collectively regarded as one step.
Conversely, steps S51 to S58 may be further divided into detailed operation steps.
There is also a method in which some of steps S51 to S58 are omitted depending on the application.

<Internal resistance measurement circuit>
FIG. 4 is a diagram illustrating an example of an internal resistance measurement circuit.
In FIG. 4, a region surrounded by a two-dot chain line 110 is an internal resistance measurement circuit of the battery 20.
In a region surrounded by a two-dot chain line 110, there are a determination circuit 111 and a load (circuit device) 601.
The internal resistance measurement of the battery 20 is performed by the determination circuit 111. However, since the internal resistance value of the battery 20 varies depending on the current (load current) flowing through the battery 20 as described later, the load 601 is included in the measurement circuit. Yes.
When measuring the internal resistance of the battery 20, the determination circuit 111 controls the load current (power consumption control 611), sets the current flowing through the battery 20 to a predetermined value, and performs the measurement.
Further, when the battery 20 has a load other than the load 601 and a current may flow through the load, the internal resistance of the battery 20 is measured by supplying a current that can be ignored. .

The power supply line 21 (+ potential) and the power supply line 22 (GND) of the battery 20 are input to the determination circuit 111. As shown in FIG. 1, the determination circuit 111 includes a battery internal resistance measurement circuit 132 in the CPU peripheral 122. The power supply lines 21 and 22 are input to the battery internal resistance measuring circuit 132.
In FIG. 4, it is also described that the output line (sensor output) 15 of the sensor 11 in contact with the battery 20 is input to the determination circuit 111. This is because the internal resistance measurement of the battery 20 may be started depending on the output state of the sensor 11.

<Outline of internal resistance measurement method>
An outline of a method for measuring the internal resistance will be described with reference to FIGS.

<Equivalent circuit of battery>
FIG. 5 is a diagram showing an equivalent circuit of the battery 711 (20: FIG. 1).
In FIG. 5, a battery 711 includes terminals 701 and 702, an internal resistance RINT of the battery, and a voltage (charge) generation source 710 that is an open-circuit voltage OCV and has no internal resistance.
The internal resistance RINT of the battery 711 has a fixed component resistance RF and a variable component resistance RV.
The resistance RF of the fixed component is a component that does not depend on the operating conditions of the battery 711 (20: FIG. 1). That is, the electrical resistance and contact resistance of the electrode metal.
The variable component resistance RV is a resistance that depends on the temperature, load current, and state of charge of the battery.
The fluctuation component resistance RV can also be expressed as the sum of the fluctuation component resistance RI based on the transient response of the current and the temperature-dependent fluctuation component resistance RT.

《Battery characteristics》
FIG. 6 is a characteristic diagram showing the relationship between the voltage, current, and internal resistance of the battery 711 (20: FIG. 1).
In FIG. 6, the horizontal axis is the time course (time chart, transient response), the vertical axis of each graph is the voltage value, current value, and resistance value, respectively, and the items are the battery voltage VBAT and the current flowing through the battery. IBAT, the resistance RI of the fluctuation component based on the transient response of the current, and V _{DROP corresponding} to the voltage drop due to the internal resistance are shown. Also denoted the time begins to conduct current IBAT and _{t 0.}

<Battery internal resistance measurement>
The internal resistance RINT of the battery is obtained by measuring the open circuit voltage OCV (current IBAT = 0) of the battery, the current IBAT flowing through the battery, and the voltage V _{DROP corresponding} to the voltage drop due to the internal resistance, that is, (OCV−VBAT). Calculated.

<Variation factors of battery internal resistance>
In the above, the internal resistance (RINT) of the battery depends on the temperature of the battery, the load current, and the state of charge of the battery (storage state, remaining battery level).
Since these elements change from moment to moment, the initial internal resistance value used in step S57 of the above-described <battery state detection flowchart> also needs to be considered.
That is, in the preset step S51 for determining the initial internal resistance value, it is necessary to grasp the temperature of the battery, the load current, and the state of charge (power storage state) of the battery and acquire data.

As described above, in the first embodiment of the present invention, even if the battery having flexibility is bent or twisted, it is determined whether there is an abnormality in the internal state of the battery even if it is used to change the shape. The product can be charged and discharged as a product.
In addition, by detecting separately the expansion caused by internal factors such as gas generation due to chemical changes inside the battery and the deformation caused by external factors to the battery, safe operation appropriate for each situation (including alerts) ) Is possible.
In addition, when measuring the internal resistance of a battery, even if the connection between the battery and the lead wire, or the connection between the lead wire and the circuit board is about to break and the resistance rises, there is a change in comparison with the initial value of the internal resistance. Therefore, not only the protection of the battery but also the security of the entire product is ensured.

«Second embodiment: battery built-in device (electronic device)»
Next, as a second embodiment of the present invention, a battery built-in device (electronic device) which is a product model incorporating a battery will be described.
With reference to FIGS. 7-9 (c), the example which attaches the sensor of the battery condition detection apparatus of 1st Embodiment of this invention to the battery built-in apparatus which is a product model with a built-in battery is demonstrated.

FIG. 7 is a diagram illustrating a configuration example of the battery built-in device according to the second embodiment of the present invention.
In FIG. 7, the battery built-in device 900 includes a display unit 901, a sensor 911, and a battery 920. Note that a circuit corresponding to the detection block (101: FIG. 1) or the determination circuit (111: FIG. 1) of the battery state detection device (100: FIG. 1) that detects the outputs of the sensor 911 and the battery 920 is shown in FIG. Since it also serves as the CPU of the display unit 901, it is not specifically shown.
The battery built-in device 900 in FIG. 7 is assumed to be mounted on, for example, an arm, and the battery 920 has flexibility and is bent in an initial state. The sensor 911 is provided in contact with the surface on one side of the battery 920. Further, part or all of the display portion 901 may have flexibility.
Further, the positional relationship between the sensor 911 and the battery 920 may be interchanged.

FIG. 8 is a diagram showing a process of bonding the sensor 11 (911: FIG. 7) and the battery 20 (920: FIG. 7) of the battery built-in apparatus 900 (FIG. 7) and the relationship according to the second embodiment of the present invention. It is.
FIG. 8 is a diagram showing the relationship between the sensor 11 (911: FIG. 7) and the battery 20 (920: FIG. 7) of the battery built-in apparatus 900 (FIG. 7) of FIG.
FIG. 8 is a diagram illustrating a state in which the sensor 11 is attached to the left end, the battery 20 is attached to the center, and the sensor 11 and the battery 20 are attached (contacted) to the right end.
As described above, the positional relationship between the sensor 11 and the battery 20 may be interchanged.

9A and 9B show the sensor 11 (911: FIG. 7, 11: FIG. 8) and the battery 20 (920: 920) of the battery built-in device 900 (FIG. 7) according to the second embodiment of the present invention. FIGS. 7 and 20 are views showing a state in which bending pressure (931) or pulling force (932) is applied in a state of being bonded (contacted) with FIG.
Regardless of the direction in which the force is applied, the sensor 11 and the surface of the battery 20 are deformed in contact with each other. That is, the deformation state of the sensor 11 reflects the deformation state of the surface of the battery 20.
When the battery is deformed, the output of the sensor changes. Further, when the battery is deformed, the resistance value as the battery also changes to some extent.

FIG. 9C is a diagram illustrating a state in which a twisting force (933) is applied to the sensor 11 and the battery 20 of the battery built-in device according to the second embodiment of the present invention.
The output change of the sensor 11 is different between the case of bending and the case of twisting. Also, the threshold for destruction is different.
Therefore, the threshold value determined by the sensor 11 is individually set according to a place where twisting is likely to occur or a place where bending is likely to occur.

In the example of the battery built-in device (product model) of the second embodiment, the display device and the battery are integrated with each other, and the sensor of this embodiment is attached to the battery side.
At this time, the battery built-in device in which the display device and the battery are integrated on the front and back sides can be continuously used when the battery is not abnormal due to simple deformation even when subjected to bending or twisting.
Therefore, the battery built-in device according to the second embodiment as a product model has flexibility, product safety is ensured, and product applications are freely and greatly expanded.

<< Other Embodiments, Modifications >>
Although the present invention has been specifically described above based on the above-described embodiment, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.
Other embodiments and modifications will be further described below.

<< Other product models of battery built-in devices (electronic equipment) >>
In the example of the battery built-in device (electronic device) of the second embodiment, the display device and the battery are integrated with each other, and the sensor of the present embodiment is attached to the battery side. However, the present invention is not limited to this.
For example, a wristwatch may be provided with a battery at the position of a belt to be worn on the arm, and the sensor used in this embodiment may be provided so as to come into contact with the battery.
Further, the detection block of the sensor used in the present embodiment may be included in or integrated with the wristwatch. Further, the CPU of the wristwatch may also be used as the CPU of the detection block of the sensor of this embodiment.
Moreover, it is not limited to a wristwatch, and may be a battery built-in device that is worn on a body other than an arm. Since the battery built-in device to be worn on the body is highly likely to be deformed, it is generally desired to be flexible.
The display device may be a battery built-in device having a video display function, a communication function, a GPS function, an Internet search function, and the like.

<Number of sensors>
In the embodiment of the present invention, the case where there are two sensors is shown, and in the modification, the case where there is one sensor is shown, but three or more sensors may be used. And you may install in the more important location where each tends to have influence on a battery.
Thus, by dividing the plurality of sensors and arranging them appropriately, there is an effect that the characteristics of the battery can be detected more effectively while reducing the area where the sensors are installed.

<Sensor type>
In 1st Embodiment of this invention, although the sensors 11 and 12 (FIG. 1) were demonstrated as a pressure sensor, it is not limited to a pressure sensor. An elastic strain sensor that detects expansion and contraction due to deformation of the sensor portion may be used. Further, the deformation may be detected by a sensor that captures a change in capacitance or a change in resistance value accompanying the deformation of the sensor portion.

<< Characteristics and thresholds of multiple sensors >>
Also, the sensor output changes differently when the sensor is bent and twisted. Also, the threshold at which the sensor breaks is different.
Therefore, the threshold value determined by the sensor may be set individually according to a place where bending is likely or a place where twisting is likely to occur. That is, the characteristic or threshold value of at least one sensor may be different from the characteristics or threshold values of other sensors due to differences in locations where a plurality of sensors are installed.
In this case, there is an effect that detection according to the characteristics of each location of the battery or the product is possible.

<Continuity of measurement flow>
As a rule, the loop of the measurement flow is turned endlessly. However, when power consumption is a concern, there may be a non-measurement time zone as detection by sampling.

<Measurement of battery internal resistance>
In the flowchart of the first embodiment, the measurement of the internal resistance of the battery is sequentially performed when there is a sensor output accompanying the deformation of the sensor, or periodically at predetermined intervals when there is no or small deformation of the sensor. However, it is not limited to this method.
For example, a method may be used in which the internal resistance value of the battery is constantly measured and the internal resistance value of the battery is compared with the initial internal resistance value when the sensor output changes.
In general, the swelling of the battery gradually increases. However, the method of constantly measuring the internal resistance of the battery described above is that even if the swelling of the battery suddenly increases, Since the internal resistance value is always known, it is possible to cope with it.
Moreover, although the flowchart of FIG. 3 described that it is a flowchart in the battery state without urgency, the method of always measuring the internal resistance of the battery described above is a countermeasure when there is urgency. It is an example of the flow of.

The invention described in the scope of claims attached to the application of this application will be added below.
The item numbers of the claims described in the appendix are as set forth in the claims attached to the application of this application.
[Appendix]
<Claim 1>
A sensor that contacts a battery package and detects a change in shape of the surface of the battery package;
A battery internal resistance measurement circuit for measuring the internal resistance of the battery;
A determination circuit for determining a state of the battery based on a change in shape of the battery by the sensor and an internal resistance of the battery by the battery internal resistance measurement circuit;
A battery state detection device comprising:
<Claim 2>
In claim 1,
The determination circuit determines whether the battery has changed due to expansion or whether the battery has been deformed by external stress based on the internal resistance of the battery.
<Claim 3>
In claim 1 or 2,
The battery state detection device, wherein the determination circuit determines whether or not the battery is abnormal based on a change in shape of the battery and an internal resistance of the battery by the battery internal resistance measurement circuit.
<Claim 4>
The battery state detection device according to any one of claims 1 to 3,
The battery;
A load driven by the power of the battery;
An electronic device comprising:
<Claim 5>
By detecting a change in the shape of the surface of the battery package by a sensor in contact with the battery package,
The battery internal resistance measurement circuit measures the internal resistance of the battery,
A battery state detection method, wherein a battery state is determined by a determination circuit based on a change in shape of the battery by the sensor and an internal resistance of the battery by the battery internal resistance measurement circuit.
<Claim 6>
In claim 5,
A battery state detection method, wherein the determination circuit determines whether the battery has changed due to expansion or whether the battery has been deformed by an external stress based on an internal resistance of the battery.
<Claim 7>
In claim 5 or 6,
A battery state detection method, wherein the determination circuit determines whether or not the battery is abnormal based on a change in shape of the battery and an internal resistance of the battery by the battery internal resistance measurement circuit.

DESCRIPTION OF SYMBOLS 11, 12 Sensor (pressure sensor, elastic strain sensor), shape change detection means 20, 711 Battery 100 Battery state detection device 101 Detection block 111 Determination circuit 121 Core 122 Peripheral 131 Sensor output calculation determination circuit, Shape change determination means 132 Battery Internal resistance measurement circuit, battery internal resistance measurement means 601 Load (circuit device)
900 Built-in battery (electronic equipment)
901 Display unit 911 Sensor (battery)
920 battery (sensor)

Claims (7)

A sensor that contacts a battery package and detects a change in shape of the surface of the battery package;
A battery internal resistance measurement circuit for measuring the internal resistance of the battery;
A determination circuit for determining a state of the battery based on a change in shape of the battery by the sensor and an internal resistance of the battery by the battery internal resistance measurement circuit;
A battery state detection device comprising: In claim 1,
The determination circuit determines whether the battery has changed due to expansion or whether the battery has been deformed by external stress based on the internal resistance of the battery. In claim 1 or 2,
The battery state detection device, wherein the determination circuit determines whether or not the battery is abnormal based on a change in shape of the battery and an internal resistance of the battery by the battery internal resistance measurement circuit. The battery state detection device according to any one of claims 1 to 3,
The battery;
A load driven by the power of the battery;
An electronic device comprising: By detecting a change in the shape of the surface of the battery package by a sensor in contact with the battery package,
The battery internal resistance measurement circuit measures the internal resistance of the battery,
A battery state detection method, wherein a battery state is determined by a determination circuit based on a change in shape of the battery by the sensor and an internal resistance of the battery by the battery internal resistance measurement circuit. In claim 5,
A battery state detection method, wherein the determination circuit determines whether the battery has changed due to expansion or whether the battery has been deformed by an external stress based on an internal resistance of the battery. In claim 5 or 6,
A battery state detection method, wherein the determination circuit determines whether or not the battery is abnormal based on a change in shape of the battery and an internal resistance of the battery by the battery internal resistance measurement circuit.

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