WO2022186363A1

WO2022186363A1 - Lithium-ion battery module

Info

Publication number: WO2022186363A1
Application number: PCT/JP2022/009265
Authority: WO
Inventors: 英明堀江; 洋志川崎; 雄介水野
Original assignee: Ａｐｂ株式会社
Priority date: 2021-03-03
Filing date: 2022-03-03
Publication date: 2022-09-09
Also published as: JP2022134442A

Abstract

A lithium-ion battery module is provided which outputs an optical signal corresponding to the state of multiple laminated battery cells that configure a battery assembly. This lithium-ion battery module includes multiple optical transmitters (10) provided on multiple battery cells (30) that configure a battery assembly (50). Each optical transmitter is configured to be provided with a control circuit (40) which receives from a measurement circuit (90) a characteristic signal representing a characteristic of the corresponding battery cell and which outputs a prescribed control signal; and a light-emitting unit (20) which outputs an optical signal, corresponding to the control signal, to an optical waveguide (60) common to the multiple optical transmitters. The control circuit (40) is provided with a state determination circuit (42) which determines the state of the corresponding battery cells on the basis of the received characteristic signal, and is configured to control the light-emitting unit (20) so as to output different-pattern control signals in response to the determined state, and to output different-pattern optical signals in response to the determined state.

Description

lithium ion battery module

TECHNICAL FIELD The present disclosure relates to a lithium-ion battery module, and more specifically, a lithium-ion battery that includes a plurality of optical transmitters that output optical signals according to the states of each of the plurality of stacked single cells that make up an assembled battery. Regarding modules.

Conventionally, an assembled battery in which multiple lithium-ion cells are stacked is used as a power source for portable electronic devices such as electric vehicles and hybrid electric vehicles. When charging such an assembled battery, it is necessary to manage charging so that there is no overcharged unit cell.

In Patent Document 1, an overcharge heat generating circuit including a light emitting diode is connected in parallel to both ends of a battery module including single cells connected in series, and when overcharge occurs, the light emitted from the light emitting diode is a common optical fiber. (see, for example, paragraphs 0012, 0023-0024 of Patent Document 1 and FIG. 5).

JP-A-11-341693

However, the structure of Patent Document 1 emits light when a unit cell is overcharged and the corresponding light-emitting diode is energized. Can not do it.

The present disclosure has been made in view of such problems, and its object is to provide a lithium-ion battery module in which each light-emitting part outputs an optical signal according to the state of the corresponding single battery. to do.

In order to achieve such an object, a lithium-ion battery module according to one embodiment of the present invention includes an assembled battery configured by stacking a plurality of single cells, and a plurality of optical transmitters provided in the plurality of single cells. each of the plurality of cells includes a positive electrode active material layer, a separator, a negative electrode active material layer, and a negative current collector; and each of the plurality of optical transmitters includes each cell and is powered by the corresponding cell,
each optical transmitter of the plurality of optical transmitters,
a measuring unit configured to output a characteristic signal representing characteristics of the corresponding cell;
a controller configured to receive the characteristic signal and output a predetermined control signal;
a light emitting unit configured to output an optical signal according to the control signal;
with
The control unit
A state determination unit that determines the state of the corresponding unit cell based on the received characteristic signal,
The light emitting unit is controlled to output control signals of different patterns according to the determined states of the corresponding single cells, and to output light signals of different patterns according to the determined states of the corresponding single cells. characterized by:

A lithium-ion battery module according to another embodiment further comprises a light-receiving section that receives an optical signal and converts it into an electrical signal, and the light-receiving section and the assembled battery are electrically insulated. do.

As described above, according to the present disclosure, it is possible to provide a lithium-ion battery module in which each light-emitting portion outputs an optical signal corresponding to the state of the corresponding cell.

1 is a partially cutaway perspective view of a lithium-ion battery module according to an embodiment of the present invention; FIG. FIG. 2 is a diagram showing a schematic cross-sectional structure of the lithium-ion battery module shown in FIG. 1; FIG. 4 is a diagram showing a schematic configuration of multiple optical transmitters in the lithium ion battery module according to one embodiment of the present invention; 1 is a diagram showing a schematic configuration of a clock generation circuit of an optical transmitter in a lithium ion battery module according to one embodiment of the present invention; FIG. FIG. 4 is a functional block diagram of a measurement circuit of an optical transmitter in the lithium ion battery module of one embodiment of the present invention; 3 is a functional block diagram of a control circuit for an optical transmitter in the lithium ion battery module of one embodiment of the present invention; FIG. FIGS. 4(a) and 4(b) are diagrams for explaining optical signals transmitted by a plurality of optical transmitters in a certain time period (ideal timing within the system cycle) in the lithium-ion battery module of one embodiment of the present invention; , and (c) are diagrams showing optical signals transmitted from different optical transmitters on the time axis, and (d) is a diagram showing the optical signals of (a), (b), and (c) in a common optical waveguide. It is a figure which shows a signal on a time-axis. FIG. 4 is a diagram for explaining optical signals transmitted by a plurality of optical transmitters in another time period (timing shifted from the ideal timing within the system cycle) in the lithium ion battery module of one embodiment of the present invention; ), (b), and (c) show optical signals transmitted from different optical transmitters on the time axis, and (d) shows (a), (b), and (d) in a common optical waveguide. It is a figure which shows the optical signal of (c) on a time-axis. FIG. 4 is a diagram for explaining the timing of an optical signal transmitted by an optical transmitter in the lithium-ion battery module of one embodiment of the present invention, (a) is a diagram showing the clock of the optical transmitter, and (b) is a diagram for measurement FIG. 4 is a diagram showing a signal indicating the state of the corresponding unit cell determined based on the characteristic signal from the circuit, FIG. FIG. 4 is a diagram showing an optical signal output according to a control signal from a circuit; 1 is a functional block diagram of a lithium-ion battery module according to one embodiment of the invention; FIG. 4 is a flowchart of signal processing of the signal processing device for the lithium-ion battery module according to one embodiment of the present invention; 1 is a block diagram showing the optical transmitter of the first embodiment and its usage; FIG. 1 is a circuit diagram showing a comparison circuit of a first embodiment; FIG. 3 is a circuit diagram showing an output circuit of the first embodiment; FIG. FIG. 4 is a diagram showing an example of the correspondence between the state of the optical transmitter of the first embodiment, the input voltage, and the output signal; FIG. 4 is a diagram showing an example of an output signal of the optical transmitter of the first embodiment; FIG. FIG. 4 is a block diagram showing an optical transmitter of a second embodiment; FIG. FIG. 11 is a block diagram showing an optical transmitter of a third embodiment; FIG. FIG. 11 is a block diagram showing an optical transmitter of a fourth embodiment; FIG. FIG. 12 is a block diagram showing an optical transmitter of a fifth embodiment; FIG. FIG. 12 is a block diagram showing an optical transmitter of a sixth embodiment; FIG. FIG. 11 is a block diagram showing an optical transmitter of a seventh embodiment; FIG. FIG. 12 is a block diagram showing an optical transmitter of an eighth embodiment; FIG. FIG. 21 is a block diagram showing an optical transmitter of a ninth embodiment; FIG. FIG. 20 is a diagram showing an example of connecting the optical transmitters of the ninth embodiment; FIG. 11 is a block diagram showing an optical transmitter of a tenth embodiment; FIG. FIG. 20 is a diagram showing an example of connecting the optical transmitters of the tenth embodiment;

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The same or similar reference numerals indicate the same or similar elements, and repeated descriptions may be omitted. It should be appreciated that the numbers and materials set forth below are exemplary, and thus the present disclosure can be practiced using other numbers and materials without departing from the spirit thereof.

A lithium-ion battery module according to one embodiment of the present invention includes an assembled battery configured by stacking a plurality of single cells, and a plurality of optical transmitters provided for the plurality of single cells. Each cell has a corresponding optical transmitter. Each optical transmitter is configured to receive a characteristic signal representing the characteristics of the corresponding unit cell and output a predetermined control signal (for example, a control signal obtained by encoding the characteristic signal for each predetermined period). A control section and a light emitting section for outputting an optical signal corresponding to a control signal to an optical waveguide common to a plurality of optical transmitters are provided. A plurality of optical transmitters are configured to asynchronously transmit optical signals.

Typically, a unit cell is made by laminating a positive electrode current collector, a positive electrode active material layer, a separator, a negative electrode active material layer, and a negative electrode current collector in this order from the bottom. The unit cell has a positive electrode in which a positive electrode active material layer is formed on the surface of a substantially rectangular plate-shaped positive electrode current collector, and a negative electrode active material layer formed on the surface of a substantially rectangular flat negative electrode current collector. and a negative electrode are laminated with a substantially flat separator interposed therebetween. In the unit cell, an annular frame member is arranged between the positive electrode current collector and the negative electrode current collector, and the frame member fixes the peripheral edge portion of the separator between the positive electrode current collector and the negative electrode current collector. , the positive electrode active material layer, the separator and the negative electrode active material layer are sealed. For example, the light emitting section may be embedded in or attached to the frame member so as to be exposed on the side surface of the frame member.

FIG. 1 is a partially cutaway perspective view of a lithium-ion battery module according to an embodiment of the present invention.

As shown in FIG. 1, the lithium ion battery module 1 has a plurality of stacked single cells 30 . The lithium-ion battery module 1 also has an optical waveguide 60 arranged adjacent to or in close proximity to the light-emitting surface of the light-emitting portion 20 . Furthermore, the lithium-ion battery module 1 has an exterior body 70 that accommodates the plurality of cells 30 and the optical waveguides 60 .

A plurality of stacked single cells 30 constitute an assembled battery 50 . Although FIG. 1 shows a configuration in which five cells 30 are stacked, more or less than five cells may be stacked. In one implementation, the number of stacks of cells 30 may be 20 or more. Each unit cell 30 has a negative electrode current collector (not shown) and a positive electrode current collector (not shown) facing the negative electrode current collector. Two adjacent cells 30 in the assembled battery 50 are stacked such that the upper surface of the negative electrode current collector of one cell 30 and the lower surface of the positive electrode current collector of the other cell 30 are adjacent to each other. FIG. 1 shows an assembled battery 50 in which five cells 30 are connected in series.

The positive electrode current collector and the negative electrode current collector are made of metal materials such as copper, aluminum, titanium, stainless steel, nickel and alloys thereof, baked carbon, conductive polymer materials, conductive glass, etc. can be configured.

A conductive sheet is provided on the uppermost negative electrode current collector of the assembled battery 50 . A part of the conductive sheet is drawn out from the outer package 70 to form the lead wiring 57 . A conductive sheet is provided under the positive electrode current collector on the bottom surface of the assembled battery 50 . A part of the conductive sheet is pulled out from the exterior body 70 to form the lead wiring 59 . The conductive sheet can be constructed using any of metal materials such as copper, aluminum, titanium, stainless steel, nickel and alloys thereof, but is not limited to these materials as long as they are conductive materials. The conductive sheet may be constructed using a conductive polymeric material.

Each cell 30 has a measurement circuit 90 that measures the characteristics of the cell. Each unit cell 30 also has a light emitting unit 20 that emits light based on the measured characteristics and outputs an optical signal. The measurement circuit 90 and the light emitting section 20 are provided in the optical transmitter 10 together with the control circuit 40 . The optical transmitter 10 will be described later.

The optical waveguide 60 has an optical output portion from which the incident and propagated optical signal is emitted. In one implementation, light emitted from light emitting units 20 provided in each of 20 or more single cells 30 arranged adjacent or close to one optical waveguide 60 is optically coupled and output from the light output unit. emit. In this embodiment, a portion of the optical waveguide 60 is pulled out from the exterior body 70 to serve as an optical output section. An optical signal emitted from the optical output section is received by the light receiving section 80 . The light receiving section 80 can be configured using a photodiode, a phototransistor, or the like. The light-receiving section 80 may be configured using an LED element, which is a light-emitting element, as a light-receiving element. The entire optical waveguide 60 including the optical output section may be housed inside the exterior body 70 . When the entire optical waveguide 60 is housed inside the exterior body 70 , the optical signal emitted from the optical output section is received by the light receiving section 80 arranged inside the exterior body 70 . Even when the light receiving section 80 is arranged inside the exterior body 70 , it is desirable that the light receiving section 80 is electrically insulated from the assembled battery 50 as in the case where the light receiving section 80 is arranged inside the exterior body 70 .

The exterior body 70 can be configured using a metal can case or a polymer-metal composite film. The exterior body 70 is sealed so as to maintain the internal pressure reduction.

FIG. 2 is a diagram showing a schematic cross-sectional structure of the lithium ion battery module shown in FIG. As shown in FIG. 2 , the optical waveguide 60 extending in the stacking direction of the unit cells is arranged adjacent to or close to the light emitting surface of the light emitting section 20 . The optical waveguide 60 may be, for example, an optical fiber, or may be a light guide plate having a sufficient width (length in the direction perpendicular to the stacking direction of the cells) to receive the optical signal from the light emitting section 20 . When the optical waveguide 60 is composed of a light guide plate, the width dimension of the optical waveguide 60 should be larger than the maximum dimension of the light emitting surface of the light emitting part 20 (diameter if the light emitting surface is circular, diagonal if rectangular). FIG. 2 shows a case where the optical waveguide 60 is configured using a light guide plate.

When a light guide plate is used as the optical waveguide 60, the optical waveguide 60 can be arranged so as to cover all of the light emitting surfaces of the plurality of light emitting portions 20 (each corresponding to a plurality of stacked single cells). Further, the optical waveguide 60 can be arranged so as to cover the light emitting direction of the light emitting section 20 (including the case where it is aligned with the vertical direction of the light emitting surface and the case where it is inclined from the vertical direction of the light emitting surface).

When a light guide plate is used as the optical waveguide 60 in this manner, the optical signal output from the light emitting unit 20 is more likely to be received than when an optical fiber is used as the optical waveguide 60. An additional component such as a lens for focusing light to 60 is no longer required, the labor for positioning the optical waveguide is reduced, or the misalignment tolerance is increased. Of course, in order to increase the coupling efficiency of the optical signal from the light emitting unit 20 to the light guide plate as the optical waveguide 60, an additional component such as a lens may be used, or a light guide plate subjected to light condensing processing may be used. Even if one or both of an additional component such as a lens and a light-condensing light guide plate are used, compared to the case of using an optical fiber as the optical waveguide 60, the complexity of positioning can be reduced or the position can be reduced. The deviation allowance is increased. Although the optical waveguide 60 extending in the stacking direction of the unit cells is exemplified, it is also possible to use the optical waveguide 60 extending in a direction orthogonal to the stacking direction of the unit cells. In this case, the light guide plate as the optical waveguide 60 can cover all of the light emitting surfaces of the plurality of light emitting portions 20, and by tapering toward the light output portion, light is output from the tapered light output portion. An optical signal can be received by the light receiver 80 .

As shown in FIG. 2, the optical waveguide 60 is subjected to scattering processing 60a at the position of the back surface corresponding to the position of the surface that receives the optical signal. The scattering processing 60a is applied to a position corresponding to the light emitting surface of the adjacent or adjacent light emitting section 20. As shown in FIG. The scattering processing 60a can be, for example, uneven processing. A portion of the optical signal that enters the optical waveguide 60 and is scattered by the scattering processing 60a propagates in the direction of the optical output section.

In addition, the optical waveguide 60 is subjected to reflection processing 60b at the bent portion, so that the optical signal scattered by the bent portion can be reflected in the direction of the optical output portion. Reflection processing 60b is applied to the end opposite to the end serving as the light output portion of the optical waveguide 60 and the bent portion. The direction of the light output can be reflected.

FIG. 3 is a diagram showing a schematic configuration of a plurality of optical transmitters within a lithium ion battery module according to one embodiment of the present invention. The optical transmitters 10 correspond to the cells 30 respectively. The optical transmitter 10 includes a light emitting section 20, a control circuit 40, and a measurement circuit 90 arranged on flexible printed circuits (FPC) (not shown).

The measurement circuit 90 is configured to measure the characteristics of the corresponding unit cell 30 and output a characteristic signal representing the measured characteristics. The measurement circuit 90 can be configured using arbitrary semiconductor elements such as microcomputers, ICs, and LSIs. The measurement circuit 90 is powered by the cell 30 . Measurement circuitry 90 may be configured to measure, for example, voltage or temperature or both as characteristics of the cell. More specifically, the measurement circuit 90 is a control circuit that is electrically coupled to voltage measurement terminals (not shown) that are in contact with the positive electrode current collector and the negative electrode current collector, respectively, and is also electrically coupled to the light emitting unit 20 . 40 are electrically coupled. The measurement circuit 90 outputs a signal indicating the voltage input to the voltage measurement terminal as a characteristic signal. The measurement circuit 90 is connected to one or more temperature measurement elements (not shown) provided in contact with the surface of the positive electrode current collector and the negative electrode current collector or the surface of the cell as an alternative or in addition to the voltage measurement terminals. may be electrically coupled. The measurement circuit 90 outputs a signal corresponding to the output from the temperature measurement element as a characteristic signal.

The control circuit 40 is configured to receive a characteristic signal representing the characteristic of the corresponding unit cell from the measurement circuit 90 and output a control signal obtained by encoding the characteristic signal every predetermined period. A control signal is supplied to the light emitting unit 20 . The control circuit 40 can be configured using any semiconductor device such as a microcomputer, IC, or LSI. Power is supplied from the cell 30 . The control circuit 40 may be integrated with the measurement circuit 90 . The control circuit may be configured to encode the identifier ID unique to the corresponding cell 30 together with the characteristic signal and output the control signal. By outputting the optical signal based on the control signal in which the identifier ID of the unit cell 30 is encoded in the corresponding control signal together with the characteristic signal, it is possible to determine which unit cell the status information is on the receiving side. can be determined or estimated.

The light emitting unit 20 can be configured using light emitting elements such as LED elements and organic EL elements. The light emitting unit 20 is powered by the cell 30 and driven based on a control signal from the control circuit 40 (that is, emits light according to the control signal and outputs an optical signal according to the control signal). can be configured.

The optical transmitter 10 is provided on the cell 30 so that the light emitting section 20 is arranged on one of the short sides of the cell 30 . Preferably, in a state in which the plurality of unit cells 30 are stacked, the light emitting surfaces of the plurality of light emitting units 20 are arranged in a row on the side surface of the assembled battery 50 in the stacking direction of the plurality of unit cells 30 and adjacent to or close to the optical waveguide 60. are placed as follows.

The optical transmitter 10 is configured to operate with an internal clock. Measurement circuit 90 and control circuit 40 operate in synchronization with an internal clock. In order to suppress the power consumption of the optical transmitter 10 which is supplied with power from the cell 30, it is preferable that the clock generation circuit also consumes less power.

FIG. 4 is a diagram showing a schematic configuration of a clock generation circuit for an optical transmitter in a lithium ion battery module according to one embodiment of the present invention. This clock generation circuit produces a square wave clock when a sinusoidal voltage generated by an oscillator circuit (not shown) such as a Colpitts circuit is applied to one (Vinp) and the other (Vinn) of the two inputs of a comparator. A circuit that outputs a signal. A CR circuit including a capacitor C and a resistor R is connected to Vinp, and the sizes of the resistor R and the capacitor C are determined according to the period or frequency of the desired square wave.

FIG. 5 is a functional block diagram of the measurement circuit 90 of the optical transmitter of this embodiment. The measurement circuit 90 includes an input terminal 91a and an input terminal 91b, a comparison circuit 92, and an output terminal 95. FIG.

The input terminal 91a and the input terminal 91b are terminals for electrically connecting the voltage measurement terminal and the measurement circuit 90, which are in contact with the positive electrode current collector and the negative electrode current collector of the cell 30, respectively. Alternatively, the input terminal 91a and the input terminal 91b are connected to one or more temperature measurement elements (not shown) provided in contact with the surface of the positive electrode current collector and the negative electrode current collector of the cell 30 or the surface of the cell. It is a terminal for electrically coupling the circuit 90 . Alternatively, the input terminal 91a and the input terminal 91b are a voltage or current sensor that measures the voltage between the positive electrode current collector and the negative electrode current collector of the cell 30, a temperature sensor provided on the surface of the cell 30, or It is a terminal for inputting a voltage output by a sensor such as a magnetic sensor provided near the surface of the cell. When a signal corresponding to a predetermined reference (for example, a voltage with reference to the ground potential) is input to the measuring circuit 90, the signal corresponding to the reference may be input to one of the

input terminals

91a and 91b. (For example, the input terminal 91b in the comparison circuit 92 may be grounded in advance so that a ground potential is supplied to the comparison circuit 92, and a signal corresponding to the reference may be input to the input terminal 91a. In this case, the comparison circuit 92 may not have the input terminal 91b for inputting a reference signal from the outside.).

The comparison circuit 92 compares the potentials input to the

input terminals

91a and 91b and outputs a signal indicating the potential difference. This potential difference corresponds to the voltage of the cell 30 or the temperature of the cell. The comparison circuit 92 can be configured using, for example, one or more comparators. By increasing the number of comparators, the granularity of the meaning (for example, the voltage of the cell 30, the temperature of the cell, or the magnetic field around the cell) indicated by the potential difference output from the output terminal 95 by the comparison circuit 92 can be increased. Can be fine or precise.

The output terminal 95 is a terminal for outputting the signal output by the comparison circuit 92 as a characteristic signal corresponding to the characteristic (voltage or temperature) of the cell 30 .

FIG. 6 is a functional block diagram of the control circuit 40 of the optical transmitter 10 in the lithium ion battery module of one embodiment of the present invention. The control circuit 40 includes a state determination circuit 42 , a lookup table 44 , a selector 43 and an output terminal 45 .

The state determination circuit 42 determines the state of the corresponding cell based on the characteristic signal output by the measurement circuit 90, and outputs a control signal having a different pattern from the output terminal 45 according to the determined state of the corresponding cell. It is a circuit configured to The state determination circuit 42 is coupled to the lookup table 44 and the selector 43 and cooperates to determine the state of the corresponding unit cell based on the characteristic signal from the measurement circuit 90. It is configured to output control signals of different patterns according to the state of .

The lookup table 44 stores values of signals (characteristic signals) indicating a plurality of potential differences that can be input from the measurement circuit 90 via the state determination circuit 42, a plurality of corresponding battery states, and a plurality of control patterns with mutually different patterns. It can be a table in which signals are associated with each other. The corresponding battery status can be, for example, a corresponding battery voltage or temperature range, and the control signal can be a signal pattern representing the corresponding battery voltage range or temperature range.

The selector 43 refers to the lookup table 44 to determine the state of the battery (for example, voltage or temperature range) corresponding to the value of the signal (characteristic signal) indicating the potential difference input via the state determination circuit 42 and the relevant A control signal (signal pattern) corresponding to the state is determined. A control signal corresponding to the determined state of the corresponding battery is output from the output terminal 45 . Selector 43 and lookup table 44 may be configured by a single circuit that sets a pulse pattern representing a signal pattern representing a battery voltage range or temperature range in response to a signal from state determination circuit 32. .

With the above configuration, each of the plurality of optical transmitters 10 outputs an optical signal corresponding to the state of the corresponding cell. Each optical transmitter 10 outputs an optical signal asynchronously with other optical transmitters.

FIG. 7 is a diagram illustrating optical signals transmitted by a plurality of optical transmitters in a certain time period (at ideal transmission timings within the system period) in the lithium-ion battery module according to one embodiment of the present invention. Assume that the assembled battery 50 is configured by stacking n unit cells (n is an integer equal to or greater than 2), and the lithium-ion battery module includes n optical transmitters corresponding to the n unit cells, respectively. . Let the system period of the lithium-ion battery module be n×T, and each optical transmitter 10 transmits an optical signal in a time period T within the system period. The ideal transmission timing within the system cycle is the timing at which the n time intervals T at which the n optical transmitters 10 transmit optical signals do not overlap.

7(a), (b), and (c) show optical signals transmitted from three optical transmitters out of n optical transmitters 10 at ideal transmission timings within the system period. Fig. 3 is a view on the axis; FIG. 7(a) shows the optical signal transmitted by the first of the three optical transmitters during the time period T from t=t0 to t=t1, and FIG. 7(b) shows the three FIG. 7(c) shows the optical signal transmitted during time period T from t=t1 to t=t2 by the second one of the optical transmitters, and FIG. is transmitted by the optical transmitter in the time period T from t=t2 to t=t3. The time period during which the first, second and third optical transmitters transmit optical signals is T, and the period (repetition time period) is nT. (d) is a diagram showing the optical signal on the optical waveguide 60 common to the n optical transmitters 10 on the time axis. The optical signals shown in FIGS. 7A, 7B, and 7C are received by the light receiving section 80 without overlapping on the optical waveguide 60. FIG. FIG. 7 shows a case where each optical transmitter transmits an optical signal with the same content, but the content of the optical signal (number of pulses and pattern) is variable according to the state of the cell. Sometimes the maximum number of pulses that can be transmitted in a time period T is transmitted as an optical signal, and if a smaller number of pulses are transmitted as an optical signal (pulses are transmitted in the first half of the time period T and pulses in the second half). not sent).

As described above, the optical transmitter 10 is configured to operate with an internal clock. Therefore, the internal clocks of all the optical transmitters 10 are not the same, and a shift occurs in the transmission timing of optical signals. The deviation of the transmission timing of the optical signal increases with the lapse of time, and the ideal transmission timing within the system period is restored. Assuming that the internal clocks of all the optical transmitters 10 are the same, the optical signal transmission timings of two or more optical transmitters 10 that transmit optical signals asynchronously can be the same. In this case, since the optical signals continue to overlap on the optical waveguide 60, a mechanism for controlling the transmission timing between the plurality of optical transmitters 10 is required. need to be synchronized.

Adding a mechanism for controlling the timing of transmission increases the cost of the optical transmitter 10 due to an increase in the number of parts, an increase in the size of the optical transmitter 10, and an increase in the number of assembly processes. Therefore, in the lithium-ion battery module of this embodiment, each of the plurality of optical transmitters 10 operates with the internal clock and transmits optical signals asynchronously with other optical transmitters. More specifically, by adjusting the magnitudes of the resistance R and the capacitance C of the CR circuit described above with reference to FIG. .

The accuracy of the clock generation circuit of this embodiment described with reference to FIG. 4 is lower than that of the clock generation circuit using a crystal oscillator. The accuracy of a silicon ^oscillator or a ceramic ^oscillator that can be mounted in a microcomputer like the clock generation circuit in FIG. The accuracy of a crystal oscillator with a built-in temperature compensation circuit is about 1×10 ⁻⁹ . In addition, the accuracy of the silicon resonator and the ceramic resonator of this embodiment includes deviation from the target accuracy at the time of manufacture (there is variation in accuracy). Therefore, the internal clock of the optical transmitter 10 is adjusted so as not to be the same as the internal clocks of other optical transmitters 10 due to manufacturing variations and/or adjustment of the CR circuit.

As described above, the light-emitting unit 20 operates and emits light according to the internal clock of the optical transmitter 10 . The internal clock of the optical transmitter 10 has temperature dependency. Therefore, the width of a pulse (length of light emission time) transmitted as an optical signal also has temperature dependence. Although the width of the optical pulse varies with temperature, if the light receiving unit 80 converts the optical signal into an electrical signal at a constant sampling interval, there is a possibility that a pulse capture error occurs (the light emitting unit 20 When the width of the light pulse is shortened on the light receiving section 80 side, two light pulses are converted into one electric pulse on the light receiving section 80 side, or when the width of the light pulse is lengthened on the light emitting section 20 side. There is a possibility that one optical pulse is converted into two electrical pulses on the light receiving section 80 side). Therefore, the light receiving section 80 may be configured to have a mechanism for changing the sampling interval when converting the received optical signal into an electrical signal according to the temperature dependency of the internal clock of the optical transmitter 10 obtained in advance. desirable.

FIG. 8 is a diagram for explaining optical signals transmitted by a plurality of optical transmitters in a certain time period (transmission timing shifted from the ideal transmission timing within the system cycle) in the lithium-ion battery module according to one embodiment of the present invention; is. Similar to FIG. 7, FIGS. 8A, 8B, and 8C are diagrams showing optical signals transmitted from three optical transmitters out of the n optical transmitters 10 on the time axis. is.

FIG. 8(a) shows the optical signal transmitted by the first optical transmitter in the time period T from t=t0 to t=t1. Taking the internal clock of the first optical transmitter as a reference, the period of the internal clock of the second optical transmitter is configured to be slightly shorter (the frequency is slightly higher), thus the time period for transmitting the optical signal is shorter than T by δ1, and the period (repetition time period) is n(T−δ1). FIG. 8(b) shows the optical signal transmitted by the second optical transmitter at a time period T-.delta.1 offset from t=t1. Also, the period of the internal clock of the third optical transmitter is configured to be slightly longer (the frequency is slightly lower) than the internal clock of the first optical transmitter, so the time to transmit the optical signal is The period is longer than T by δ2, and the period (repeating time period) is n(T+δ2). FIG. 8(c) shows the optical signal transmitted by the third optical transmitter at a time period T+.delta.2 offset from t=t2. (d) is a diagram showing the optical signal on the optical waveguide 60 common to the n optical transmitters 10 on the time axis. The optical signals shown in FIGS. 8(a), (b), and (c) are superimposed on the optical waveguide 60 and received by the light receiving section 80. FIG. By overlapping the optical signals on the optical waveguide 60, for example, the number of optical pulses included in the optical signal in the time period T from t=t0 to t=t1, the width of the optical pulses, or at least part of the array pattern , changes from the optical pulse contained in the optical signal output by the first optical transmitter. In the example of FIG. 9(d), the second pulse from the back within the time period T from t=t0 to t=t1 is added, the width of the first pulse from the back is widened, and the optical signal The arrangement of the light pulses of is changing. This change also appears in the electrical signal from the light receiving section 80 . Therefore, at least one of the plurality of optical signals output from the plurality of optical transmitters 10 is based on at least one of the number of electrical pulses contained in the electrical signal from the light receiving section 80, the width of the electrical pulses, and the arrangement of the electrical pulses. It can be determined whether a portion overlaps on the light guide 60 .

FIG. 9 is a diagram illustrating the timing at which the optical transmitter transmits optical signals in the lithium-ion battery module according to one embodiment of the present invention. Taking the first optical transmitter 10 described with reference to FIGS. 7 and 8 as an example, the optical transmitter 10 transmits light during a time period T from t=0 to t=1 within the time period nT of the system period. The timing for transmitting signals will be explained.

FIG. 9(a) is a diagram showing the internal clock of the optical transmitter 10 on the time axis. Measurement circuit 90 and control circuit 40 operate according to this internal clock.

FIG. 9(b) is a diagram showing a signal indicating the state of the corresponding cell determined by the control circuit 40 based on the characteristic signal from the measurement circuit 90. FIG. The signal indicating the state of the cell differs (changes) according to the state of the cell. In the measurement circuit 90, the comparison circuit 92 outputs a characteristic signal indicating the potential difference (voltage of the cell) between the two input terminals according to the internal clock. In the control circuit 40, the state determination circuit 42 determines the state of the corresponding cell based on the characteristic signal from the measurement circuit 90 according to the internal clock, and determines the state of the corresponding cell according to the state of the corresponding cell. judge the signal. Determination of different patterns of signals according to the corresponding state of the cell and the determined state of the cell may be performed using the selector 43 and the lookup table 44 . Quantization errors occur when the measurement circuit 90 outputs the characteristic signal and when the control circuit 40 outputs the control signal. FIG. 9(b) illustrates the case where the potential difference between the two input terminals of the measuring circuit 90 does not change within the time period nT of the system cycle from t=0. The signal (number of pulses and pattern) corresponding to the state of the cell determined by the control circuit 40 changes according to the change in the potential difference between the cells (the state of the cell).

FIG. 9(c) is a diagram showing a signal indicating a predetermined time period T (the repetition period is nT) in the time period nT of the system period. The control circuit 40 uses a clock counter (not shown) that counts an internal clock to count the time period nT of the system cycle and a predetermined time period T within the time period nT, and generate a signal indicating the predetermined time period. can be generated. The control circuit 40 encodes the characteristic signal together with a signal indicating a predetermined time period and outputs a control signal. The control signal supplied from the control circuit 40 to the light emitting unit 20 is the product of the characteristic signal shown in FIG. 9(b) and the signal indicating the predetermined period shown in FIG. 9(c).

FIG. 9(d) is a diagram showing an optical signal output when the light emitting section 20 emits light according to the control signal supplied from the control circuit 40. FIG. The pattern signal corresponding to the state of the unit cell corresponding to the characteristic signal output from the measuring circuit 90 determined by the control circuit 40 after t=t1 shown in FIG. 9B is not encoded into the control signal. (or encoded into a series of 0's) and therefore not output as an optical signal. In the period after t=t1 in the time period nT of the system period, the remaining n−1 optical transmitters (for example, the second optical transmitter, the third optical transmitter, . . . If the optical transmitters) transmit optical signals at different timings, the optical signals are received by the light receiving section 80 without overlapping on the optical waveguide 60 as shown in FIG. 7(d).

As described above, at the ideal transmission timing within the system period, the optical signals are received by the light receiving section 80 without overlapping on the common optical waveguide 60 as shown in FIG. 7(d). At the subsequent transmission timing that deviates from the ideal transmission timing within the system cycle, the optical signals overlap on the optical waveguide 60 and are received by the light receiving section 80 as shown in FIG. 8(d). Further, at the ideal transmission timing within the subsequent system period, the optical signals are received by the light receiving section 80 without overlapping on the common optical waveguide 60 as shown in FIG. 7(d) again. Thus, in the lithium-ion battery module of the present embodiment, the ideal transmission timing within the system cycle occurs in a relatively long cycle, and based on the optical signals received from the plurality of optical transmitters 10 at this time, , it is possible to determine the characteristics of a plurality of single cells.

A method for determining or estimating the characteristics of a cell at transmission timings that deviate from the ideal transmission timings within the system cycle shown in FIG. 8(d) will be described below.

FIG. 10 is a functional block diagram of a lithium ion battery module according to one embodiment of the present invention. The lithium-ion battery module comprises a signal processor 100 configured to determine or estimate the state of the plurality of cells, taking into account additional information apart from the electrical signal converted from the optical signal by the light receiver 80 .

As shown in FIG. 10, the lithium ion battery module 1 includes a voltmeter 120 for measuring the input/output voltage of the assembled battery connected to the lead wiring 57 and the lead wiring 59 . The lithium ion battery module 1 also includes an ammeter 110 connected to the lead wire 57 for measuring the input/output current of the assembled battery. The input/output voltage information obtained from the voltmeter 120 and the input/output current information obtained from the ammeter 110 can be used as additional information when determining or estimating the states of the plurality of cells. Time series and prior knowledge can also be used when determining or estimating the states of a plurality of single cells. The time series can be an information table in which the states determined by the state determination unit 102 are recorded in chronological order. The prior knowledge includes an information table showing the correspondence relationship between preset cell characteristics (internal states such as voltage and temperature) and the length of the characteristic signal output by the measuring circuit 90, cell characteristics (voltage and temperature , etc.) can be information indicating state transitions. The time series and prior knowledge can be information recorded on a computer-readable recording medium.

The signal processing device 100 includes a state determination section 102 and a state estimation section 104 . Signal processing device 100 may be a computing device that includes a memory, a processor, and a computer-readable storage medium that records a program that causes the processor to function as state determining section 102 and state estimating section 104 . The computer-readable storage medium may record information indicating the above-described prior knowledge in addition to the program.

Even at transmission timings that deviate from the ideal transmission timing within the system period, optical signals transmitted from a plurality of optical transmitters are received by the light receiving unit 80 as long as they do not overlap, and the optical transmitter that transmitted the optical signals can correctly determine the characteristics of the cell corresponding to . Therefore, as shown in FIG. 11, first, the state (characteristics) of the cell 30 is determined by the state determining unit 102 based on the electrical signal from the light receiving unit 80 (step S11), and the states of all the cells are determined. It is determined whether or not the states have been determined (step S12), and the states of the single cells whose states could not be determined are estimated by the state estimating unit 104 (step S13). A specific example of a method for determining or estimating the voltage of a cell as a characteristic of the cell will be described below.

The state determination unit 102 processes the electrical signal from the light receiving unit 80 and determines whether or not it is converted from an optical signal in which two or more optical signals are superimposed. For example, it can be determined whether two or more optical signals overlap based on the number of pulses, the width of the pulses, and the pattern of pulse sequences contained in the electronic signals. If it is determined that the electrical signal is not converted from an optical signal in which two or more optical signals are superimposed, the state determining unit 102 determines that the voltage indicated by the electrical signal is the voltage of the cell 30. decide.

The state estimator 104 estimates the voltages of the cells that have not been determined by the state determiner 102 . The state estimator 104 uses the input/output voltage information obtained from the voltmeter 120 . Assuming that the input/output voltage information Vtotal of the assembled battery 50 composed of n unit cells 30 connected in series and the sum of the voltages of the plurality of unit cells being V1+V2+V3+ . . . . The state estimator 104 transitions the voltage of the cell that could not be determined by the state determiner 102 by using the relationship of Equation 1. FIG.
Vtotal=V1+V2+V3+...Vn (Formula 1)

The state estimation unit 104 obtains the difference between Vtotal and the sum of the voltages of the cells determined by the state determination unit 102, and estimates the voltages of the cells that were not determined by the state determination unit 102 based on the obtained difference. can do. Here, the cell voltage determined by state determination section 102 may include quantization errors in measurement circuit 90 and control circuit 40 . Therefore, it is preferable to estimate the voltages of the single cells that have not been determined by the state determining unit 102, taking into account this error range. Let m (m be an integer) be the number of cells whose voltages are determined by the state determination unit 102, let Sm be the lower limit of the voltage range represented by the electrical signal, and SM be the upper limit. The voltage range Vrng_ND of the unit cells that have not been energized can be expressed by Equation (2). The state estimating unit 104 can estimate the voltage of the cell that was not determined by the state determining unit 102 within this range.
Vtotal-(SM1+SM2+...SMm)<Vrng_ND<Vtotal-(Sm1+Sm2+...Smm) (Formula 2)

In addition, the state estimating section 104 can estimate the voltage of the cell that was not determined by the state determining section 102 at a certain timing based on the time series. For example, the state estimating unit 104 determines the voltage of the unit cell that was not determined by the state determining unit 102 at a certain timing by the state determining unit 102 at least at one of the timing before and after that timing. It can be estimated based on the determined voltage of the unit cell. For example, assume that the voltages of the single cells determined by the state determining unit 102 at t=t0 and t=t2 are equal to V1. At this time, based on this time series, state estimating section 104 determines that the voltages of the single cells that were not determined by state determining section 102 at t=t1 are V0 and V1 close to V1 (the difference from V1 is not large). or V2 (V0<V1<V2). In another example, it is assumed that the cell voltage determined by the state determination unit 102 at t=t0 is V1, and the cell voltage determined by the state determination unit 102 at t=t2 is V3. At this time, based on this time series, state estimating section 104 determines that the voltage of the cell that was not determined by state determining section 102 at t=t1 is close to V1 or V3 (the difference from V1 or V3 is not large). ) V1, V2 or V3 between V1 and V3 (V1<V2<V3).

Furthermore, the state estimating unit 104 can use prior knowledge to estimate the voltage of the cell that was not determined by the state determining unit 102 at the timing. As prior knowledge, a voltage-capacity curve measured in advance is held, and the state estimating unit 104 uses a value that fits the voltage-capacity curve to determine the state of a single cell of a certain voltage after charging a predetermined amount. A voltage change or voltage at the battery can be estimated.

The state estimation unit 104 uses one or more of estimation using additional information, estimation based on time series, and estimation using prior knowledge to estimate the voltage of the cell that was not determined by the state determination unit 102 at the timing. be able to.

As described above, in a time period that deviates from the ideal period within the system period, the optical signals are received by the light receiving section 80 while being superimposed on the optical waveguide 60 as shown in FIG. 8(d). It becomes possible to estimate the state of the cell.

Various examples of the optical transmitter 10 in the lithium ion battery module according to the above embodiment will be described in detail below with reference to the drawings.

[First embodiment]
The configuration of the optical transmitter 10 of the first embodiment will be described with reference to FIG. FIG. 12 is a block diagram showing the optical transmitter 10 and its usage in the first embodiment. 12, the optical transmitter 10 of this embodiment includes a comparison circuit 92, a state determination circuit 42, a pulse pattern setting circuit 233, a reset circuit 234, a clock generation circuit 235, and an output circuit 236. FIG. The optical transmitter 10 also includes a VDD terminal 221 , a VSS terminal 222 , an input terminal 224 and an output terminal 223 . The optical transmitter 10 further includes a light emitter 20 (not shown).

The VDD terminal 221 is connected to the power supply VDD inside the optical transmitter 10 . The VSS terminal 222 is connected to the power supply VSS within the optical transmitter 10 . Input terminal 224 is connected to comparison circuit 92 . Comparing circuit 92 is connected to state determining circuit 42 . The state determination circuit 42 is connected to the comparison circuit 92 and the pulse pattern setting circuit 233 . The pulse pattern setting circuit 233 is connected to the state determination circuit 42 , the reset circuit 234 , the clock generation circuit 235 and the output circuit 236 . The reset circuit 234 is connected to the pulse pattern setting circuit 233 and the clock generation circuit 235 . The clock generation circuit 235 is connected to the reset circuit 234 and the pulse pattern setting circuit 233 . The output circuit 236 is connected to the pulse pattern setting circuit 233 and the output terminal 223 . Part of the description of the power connection of each circuit in the optical transmitter 10 is omitted. The cell 30 is connected to a VDD terminal 221 and a VSS terminal 222 which are cell connection terminals of the optical transmitter 10 . The sensor 205 has three terminals of power supply and output. The sensor 205 operates using the cell 30 as a power source. The sensor 205 applies a voltage based on the voltage of the VSS terminal 222 from the output terminal to the input terminal 224 as the input voltage VIN. The optical transmitter 10 outputs from the output terminal 223 an output signal OUT corresponding to the voltage range of the voltage applied to the input terminal 224 . An output signal OUT corresponding to the characteristic signal is supplied to the light emitting section 20 (not shown).

Next, the configuration of the comparison circuit 92 of the first embodiment will be described with reference to FIG. FIG. 13 is a circuit diagram showing the comparison circuit 92 of the first embodiment. The comparison circuit 92 includes

resistor circuits

301 and 302 that generate voltages to be input to the comparators,

comparators

303 and 304 , and a voltage source 305 . The resistor circuit 301 has

switches

306 and 307 and

resistors

310 , 311 and 312 . Switch 306 , resistor 310 and resistor 312 are connected in series between VDD terminal 221 and VSS terminal 222 . Similarly, switch 307, resistor 311, and resistor 312 are connected in series between input terminal 224 and power supply VSS. Resistor circuit 302 has

switches

308 and 309 and

resistors

313 , 314 and 315 . Switch 308, resistor 313, and resistor 315 are connected in series between input terminal 224 and power supply VSS. Similarly, switch 309, resistor 314, and resistor 315 are connected in series between input terminal 224 and power supply VSS. The comparator 303 has an inverting input terminal connected to the power supply VSS2 via the voltage source 305, and a non-inverting input terminal connected to the connection point of the

resistors

310, 311, and 312. FIG. Similarly, the comparator 304 has an inverting input terminal connected to the power supply VSS via the voltage source 305 and a non-inverting input terminal connected to the connection point of the

resistors

313 , 314 , and 315 . Outputs of the

comparators

303 and 304 are connected to the state determination circuit 42 .

The state determination circuit 42 determines in which voltage range the input voltage VIN input to the input terminal 224 is positioned according to the output determination result of the input comparator, and sets a new monitoring voltage range according to the determination. Thus, a control signal for setting the

switches

306, 307, 308, and 309 of the comparison circuit 92 on and off is output. Further, the state determination circuit 42 outputs to the pulse pattern setting circuit 233 in which monitor voltage range the input voltage VIN falls. The state determination circuit 42 can be composed of a logic circuit, a processor circuit, or the like.

The pulse pattern setting circuit 233 is a circuit implementing functions corresponding to the selector 43 and lookup table 44 described above. The pulse pattern setting circuit 233 receives the output of the state determination circuit 42 and outputs a pulse-shaped output signal OUT corresponding to the voltage range of the input voltage VIN from the sensor 205 from the output terminal 223 via the output circuit 236 . Signals from the reset circuit 234 and the clock circuit 35 are used to generate the pulse pattern of the output signal OUT. The operations of the pulse pattern setting circuit 233, reset circuit 234, and clock circuit 35 will be described later.

The configuration of the output circuit 236 will be described with reference to FIG. The output circuit 236 has an input, an output, a PMOS transistor 361 and an NMOS transistor 362 . The PMOS transistor 361 has a gate terminal connected to the input of the output circuit 236 , a source terminal connected to the power supply VDD, and a drain terminal connected to the output of the output circuit 236 . The NMOS transistor 362 has a gate terminal connected to the input of the output circuit 236 , a source terminal connected to the power supply VSS, and a drain terminal connected to the output of the output circuit 236 .

The operation of the input voltage VIN of the input terminal 224 to which the sensor 205 is connected, the comparison circuit 92, and the state determination circuit 42 will be described with reference to FIG. The input voltage VIN is the voltage applied from the sensor 205 to the input terminal 224 with reference to the voltage of the VSS terminal 222 . Voltage source 305 supplies a reference voltage VREF to the inverting input terminals of

comparators

303 and 304 .

The non-inverting input terminal of the comparator 303 is applied with a voltage obtained by dividing the single cell voltage VBAT by the resistor circuit 301 by turning on either of the

switches

306 and 307 . The input voltage VIN when the voltage applied to the non-inverting input terminal of the comparator 303 when the switch 306 is on is equal to the reference voltage VREF is defined as the voltage VDET1. The input voltage VIN when the voltage applied to the non-inverting input terminal of the comparator 303 when the switch 307 is on is equal to the reference voltage VREF is defined as the voltage VDET3.

A voltage obtained by dividing the input voltage VIN by the resistor circuit 302 is applied to the non-inverting input terminal of the comparator 304 by turning on either of the

switches

308 and 309 . The input voltage VIN when the voltage applied to the non-inverting input terminal of the comparator 304 when the switch 308 is on is equal to the reference voltage VREF is defined as the voltage VDET2. The input voltage VIN when the voltage applied to the non-inverting input terminal of the comparator 304 when the switch 309 is on is equal to the reference voltage VREF is assumed to be the voltage VDET4. For the voltages VDET1, VDET2, VDET3, and VDET4, the resistance values of the resistors 310 to 315 are set so that the magnitude relationship is voltage VDET1>voltage VDET2>voltage VDET3>voltage VDET4.

The relationship between the input voltage VIN, the voltages VDET1 to VDET4, and the state (STATE) will be described with reference to FIG. FIG. 15 is a diagram showing the correspondence between the state of the optical transmitter, the input voltage VIN, and the output signal OUT. A voltage state in which the input voltage VIN is equal to or higher than the voltage VDET1 is STATE1. A voltage state in which the input voltage VIN is equal to or higher than the voltage VDET2 and lower than the voltage VDET1 is STATE2. A voltage state in which the input voltage VIN is equal to or higher than the voltage VDET3 and lower than VDET2 is STATE3. A voltage state in which the input voltage VIN is equal to or higher than the voltage VDET4 and lower than the voltage VDET3 is STATE4. A voltage state in which the input voltage VIN is less than the voltage VDET4 is STATE5. Although the boundary voltage is included in the upper STATE here, it is possible to arbitrarily set whether the boundary voltage is included in the upper or lower STATE.

In the comparison circuit 92 of FIG. 13, for example, the

switches

306 and 308 are turned on. A voltage obtained by dividing the input voltage VIN by

resistors

310 and 312 is input to the non-inverting input terminal of the comparator 303 , and a voltage obtained by dividing the input voltage VIN by

resistors

313 and 315 is input to the non-inverting input of the comparator 304 . is entered. Based on the above-described voltage relationship, the comparison circuit 92 sets the voltage VDET1 as the upper reference voltage and the voltage VDET2 as the lower reference voltage for monitoring the input voltage VIN, and sets the monitoring voltage range. Based on the output of the comparison circuit 92, the state determination circuit 42 determines in which voltage range of the voltage states (STATE1 to STATE5) the input voltage VIN is located, and outputs the determination result to the pulse pattern setting circuit 233. do. Also, according to the determination result, it outputs a control signal for setting ON/OFF of the switch of the comparison circuit 92 so as to set a new monitoring voltage range.

Here, it is assumed that the input voltage VIN changes from the state of STATE2, which is the voltage state equal to or higher than the voltage VDET2 and lower than the voltage VDET1, and the input voltage VIN becomes lower than the voltage VDET2. The state determination circuit 42 outputs a control signal for turning off the switch 306 and turning on the switch 307 . The voltage range monitored by the comparison circuit 92 is a voltage range equal to or higher than the voltage VDET3 and lower than the voltage VDET2. When the input voltage VIN is within this voltage range, the voltage state is STATE3. Further, when the input voltage VIN changes to be less than the voltage VDET3, the state determination circuit 42 outputs a control signal for turning off the switch 308 and turning on the switch 309. FIG. The monitoring voltage range of the comparison circuit 92 is equal to or higher than the voltage VDET4 and lower than the voltage VDET3, and the voltage state is STATE4 when the input voltage VIN is within this voltage range. In this manner, the state determination circuit 42 outputs the switch control signal according to the determination result of the comparison circuit 92, so that the monitoring voltage range can be sequentially switched. can be monitored. If the input voltage VIN is ramped up, the optical transmitter switches to the opposite action.

Next, the overall operation of the optical transmitter 10 will be described with reference to FIG. The optical transmitter 10 can obtain states (STATE) corresponding to five voltage states as shown in FIG. Based on the output of the comparison circuit 92 , the state determination circuit 42 outputs to the pulse pattern setting circuit 233 a signal indicating in which voltage range the input voltage VIN is located. Based on the clock signal supplied from the clock generation circuit 235, the pulse pattern setting circuit 233 converts a predetermined pulse group consisting of a predetermined pulse width and a predetermined number of pulses preset according to each state into a predetermined pulse group. A predetermined voltage pulse or current pulse is output through the output circuit 236 repeatedly for each cycle. The state determination circuit 42 and the pulse pattern setting circuit 233 are composed of a logic circuit or a processor circuit operated by a program.

The reset circuit 234 receives a signal from the pulse pattern setting circuit 233 every predetermined cycle and operates to initialize the pulse pattern setting circuit 233, thereby resetting the pulse pattern with a predetermined pulse width and a predetermined number of pulses. The configured predetermined pulse group is repeatedly output for each predetermined pulse period.

An example of pulse output allocation in this embodiment is shown in FIG. FIG. 15 shows the correspondence between each voltage state (STATE), the input voltage VIN, the pulse width (Output Pulse Width), the number of pulses forming a pulse group (Output Pulse Number), and the pulse cycle (Output Pulse Cycle). An example of the output signal OUT is shown in FIG. For example, when the input voltage VIN takes a voltage value (STATE1) equal to or higher than the voltage VDET1, the predetermined pulse group consists of two voltage pulses with a pulse width of 128 ms with a pulse interval of 128 ms, and the pulse group is repeatedly output. The period is 1024ms. A combination of pulse width, pulse interval and number of pulses within a predetermined pulse period is called a pulse pattern. Although FIG. 16 shows the case where the output signal OUT is a voltage pulse, the output signal OUT may be a current pulse. The pulse output is assigned a pulse with a large pulse width that increases current consumption when the input voltage VIN is high, and a pulse with a small pulse width that reduces current consumption when the battery voltage VBAT is low due to battery exhaustion. assign. By allocating the pulse output in this way, it is possible to extend the life of the single cell when the single cell voltage VBAT becomes low.

A microcomputer (not shown) that determines the voltage of the sensor 205 from the voltage pulse or current pulse from the output terminal 223 of the optical transmitter 10 determines the pulse width and the number of pulses of the pulse group output from the optical transmitter 10. can obtain the voltage information of the sensor 205 output. The monitoring microcomputer determines the pulse group output from the optical transmitter 10 with reference to the master clock. In determining the pulse group, the microcomputer measures the time from the first pulse width of the pulse group to the subsequent pulse for each pulse period, and based on the first measured time, the similar waveform subsequent pulse is the time STATE can be determined by counting the number of shots similar to . A voltage pulse or current pulse from the output terminal 223 of the optical transmitter 10 is used to determine the voltage of the sensor 205 . Similarly, the signal processing device 100 for judging the voltage of the sensor 205 by means of light pulses emitted from the light emitting section 20 (not shown) of the optical transmitter 10 determines the pulse width of the light pulse group and the number of light pulses to determine the sensor voltage. 205 output voltage information can be obtained.

In the optical transmitter 10 of this embodiment, the pulse pattern of the output signal OUT is generated based on the clock generated by the clock generation circuit 235, and the clock generation circuit 235 is a CR oscillation circuit or the like described with reference to FIG. consists of a general oscillator circuit. The clock period output from the CR oscillation circuit varies depending on the power supply voltage, temperature, etc., but as described above, the state determination by the microcomputer is based on time measurement for the first pulse pattern and subsequent similar pulse patterns. Determined by counting the number of shots. The clock generation circuit 235 of the optical transmitter 10 can output pulses that enable state determination even if the accuracy is not high. Therefore, the optical transmitter 10 does not require a high-precision reference source such as a crystal oscillator, and a voltage monitoring system can be configured easily and inexpensively.

As described above, in the optical transmitter 10 of this embodiment, the pulse pattern setting circuit 233 generates a predetermined pulse group composed of a predetermined pulse width and a predetermined number of pulses according to the voltage range of the input voltage VIN. is repeatedly output every predetermined pulse period. The optical transmitter 10 of the present embodiment can periodically confirm that the input voltage VIN is within a predetermined voltage range for each predetermined pulse period. By monitoring the predetermined pulse pattern with a microcomputer or the like, it is possible to confirm at predetermined intervals that the output of the sensor 205 is within a predetermined voltage range. It is possible to periodically determine whether or not there is a failure in the monitoring circuit such as The comparison circuit 92 of this embodiment has four reference voltages and five monitoring voltage ranges. By adopting a configuration in which switches are switched, it is possible to further subdivide the monitoring voltage range.

Although reset circuit 234 receives signals from pulse pattern setting circuit 233 every predetermined pulse period to operate, reset circuit 234 receives signals from both state determination circuit 42 and pulse pattern setting circuit 233 . , and initializes the clock generation circuit 235 and the pulse pattern setting circuit 233 every time the state determination circuit 42 changes or the pulse pattern setting circuit 233 outputs a predetermined cycle.

In the above configuration, when the output of the sensor 205 fluctuates, deviates from the predetermined voltage range, and the state changes, it becomes possible to output a predetermined pulse pattern. The sensor 205 may be any device that outputs a voltage depending on the physical quantity to be sensed, and examples thereof include a temperature sensor and a magnetic sensor, but are not limited to these.

[Second embodiment]
The configuration of the optical transmitter 10a of the second embodiment will be described with reference to FIG. The same components as in the first embodiment are assigned the same numbers as in the first embodiment, and descriptions thereof are omitted. FIG. 17 is a block diagram showing the optical transmitter 10a in the second embodiment. The optical transmitter 10a further includes a light emitting section 20 (not shown).

The optical transmitter 10a of this embodiment includes a sensor circuit 237 instead of the input terminal 224 of the optical transmitter 10 of the first embodiment. The comparison circuit 92 is connected to the sensor circuit 237 instead of the input terminal 224 . The optical transmitter 10 a of this embodiment applies the sensor voltage output by the sensor circuit 237 to the comparison circuit 92 . The sensor voltages are compared by the comparator of the comparison circuit 92 and the result is output to the state determination circuit 42 .

The state determination circuit 42 determines in which voltage range the sensor voltage output by the sensor circuit 237 is positioned according to the inputted output determination result of the comparator, and sets a new monitoring voltage range according to the determination. A control signal for setting the

switches

306, 307, 308, and 309 of the comparison circuit 92 on and off is output. Also, the state determination circuit 42 outputs a signal to the pulse pattern setting circuit 233 indicating in which monitor voltage range the sensor voltage is. The pulse pattern setting circuit 233 receives the output of the state determination circuit 42 and outputs a pulse-shaped output signal OUT corresponding to the sensor voltage output by the sensor circuit 237 via the output circuit 236 . An output signal OUT corresponding to the characteristic signal is supplied to a light emitting section 20 (not shown) and a monitoring microcomputer (not shown).

As described above, in the optical transmitter 10a of this embodiment, the pulse pattern setting circuit 233 is configured with a predetermined pulse width and a predetermined number of pulses according to the voltage range of the sensor voltage output from the sensor circuit 237. A predetermined pulse group is repeatedly output for each predetermined pulse period. The optical transmitter 10a of this embodiment can periodically confirm that the sensor voltage output by the sensor circuit 237 is within a predetermined voltage range at each predetermined pulse period. The sensor circuit 237 may output a voltage according to the physical quantity to be sensed, and examples thereof include a temperature sensor circuit and a magnetic sensor circuit, but are not limited to these.

[Third embodiment]
The configuration of the optical transmitter 10b of the third embodiment will be described with reference to FIG. The same components as in the first embodiment are assigned the same numbers as in the first embodiment, and descriptions thereof are omitted. FIG. 18 is a block diagram showing the optical transmitter 12 in the third embodiment. The optical transmitter 10b further includes a light emitter 20 (not shown).

The optical transmitter 10b of this embodiment is configured by connecting the VDD terminal 221 to the comparison circuit 92 instead of the input terminal 224 of the optical transmitter 10 of the first embodiment. The VDD terminal 221 is connected to the power supply VDD and the comparison circuit 92 inside the optical transmitter 10b. The optical transmitter 10 b of this embodiment applies the cell voltage VBAT of the cell 30 applied to the VDD terminal 221 to the comparison circuit 92 . The cell voltage VBAT is compared by the comparator of the comparison circuit 92 and the result is output to the state determination circuit 42 .

The state determination circuit 42 determines in which voltage range the unit cell voltage VBAT of the unit cell 30 is positioned according to the inputted output determination result of the comparator, and sets a new monitoring voltage range according to the determination. A control signal for setting the

switches

306, 307, 308, and 309 of the comparison circuit 92 on and off is output. In addition, the state determination circuit 42 outputs a signal to the pulse pattern setting circuit 233 to indicate in which monitor voltage range the cell voltage VBAT is. The pulse pattern setting circuit 233 receives the output of the state determination circuit 42 and outputs a pulse-shaped output signal OUT corresponding to the voltage range of the single battery voltage VBAT via the output circuit 236 . An output signal OUT corresponding to the characteristic signal is supplied to a light emitting section 20 (not shown) and a monitoring microcomputer (not shown).

As described above, in the optical transmitter 10b of this embodiment, the pulse pattern setting circuit 233 is configured with a predetermined pulse width and a predetermined number of pulses according to the voltage range of the cell voltage VBAT of the cell 30. A predetermined pulse group is repeatedly output for each predetermined pulse period. The optical transmitter 10 of this embodiment can periodically confirm that the cell voltage VBAT of the cell 30 is within a predetermined voltage range at every predetermined pulse period.

[Fourth embodiment]
The configuration of the optical transmitter 10c of the fourth embodiment will be described with reference to FIG. The same components as in the first embodiment are assigned the same numbers as in the first embodiment, and descriptions thereof are omitted. FIG. 19 is a block diagram showing an optical transmitter 10c in the fourth embodiment. The optical transmitter 10c of this embodiment comprises a second comparison circuit 92a having the same configuration as the comparison circuit 92 in the optical transmitter 10 of the first embodiment. Also, instead of the state determination circuit 42, a state determination circuit 42a is provided. The state determination circuit 42a receives inputs from the comparison circuit 92 and the second comparison circuit 92a, and outputs a control signal for setting the switches of the comparison circuit 92 and the second comparison circuit 92a. The optical transmitter 10c further includes a light emitter 20 (not shown).

The input terminal 224 is connected to the state determination circuit 42a via the second comparison circuit 92a. In the optical transmitter 10 c of this embodiment, the VDD terminal 221 is connected to the power supply VDD and the comparison circuit 92 inside the optical transmitter 10 . The sensor 205 uses the cell 30 as a power source and applies a sensor voltage based on the voltage of the VSS terminal 221 to the input terminal 224 . The input terminal 224 is connected to the second comparison circuit 92a.

The comparison circuit 92 is connected to the state determination circuit 42a, and similarly the second comparison circuit 92a is connected to the state determination circuit 42a. The state determination circuit 42a outputs to the pulse pattern setting circuit 233 a signal indicating in which voltage range the monitoring voltage ranges of the comparison circuit 92 and the second comparison circuit 92a are. The pulse pattern setting circuit 233 receives the output of the state determination circuit 42 and outputs a pulse-shaped output signal OUT corresponding to the voltage input to the VDD terminal 221 and the input terminal 224 via the output circuit 236 . An output signal OUT corresponding to the characteristic signal is supplied to a light emitting section 20 (not shown) and a monitoring microcomputer (not shown).

The pulse pattern output from the pulse pattern setting circuit 233 is one of 25 states obtained by combining five voltage ranges (STATE), which are monitoring voltage ranges of the comparison circuit 92 and the second comparison circuit 92a. Alternatively, a pulse pattern representing the voltage range of the comparison circuit 92 and a pulse pattern representing the voltage range of the second comparison circuit 92a may be repeated.

As described above, in the optical transmitter 10c of this embodiment, the pulse pattern setting circuit 233 responds to the voltage range of the input voltage VIN input to the input terminal 224 and the cell voltage VBAT of the cell 30. A predetermined pulse group composed of a predetermined pulse width and a predetermined number of pulses is repeatedly output for each predetermined pulse period. The optical transmitter 10c of this embodiment can periodically confirm that the input voltage VIN and the cell voltage VBAT are within a predetermined voltage range at each predetermined pulse period.

[Fifth embodiment]
The configuration of the optical transmitter 10d of the fifth embodiment will be described with reference to FIG. The same components as in the fourth embodiment are assigned the same numbers as in the fourth embodiment, and descriptions thereof are omitted. FIG. 20 is a block diagram showing an optical transmitter 10d in the fifth embodiment. The optical transmitter 10d further includes a light emitting section 20 (not shown).

The optical transmitter 10 d of this embodiment is configured by connecting the VDD terminal 221 to the comparison circuit 92 . The VDD terminal 221 is connected to the power supply VDD and the comparison circuit 92 inside the optical transmitter 10b. Further, instead of the input terminal 224 of the optical transmitter 10 of the first embodiment, a sensor circuit 237 and a second comparison circuit 92a are provided. The second comparison circuit 92a is connected to the state determination circuit 42a.

The comparison circuit 92 is connected to the state determination circuit 42a, and similarly the second comparison circuit 92a is connected to the state determination circuit 42a. The state determination circuit 42a outputs to the pulse pattern setting circuit 233 a signal indicating in which voltage range the monitoring voltage ranges of the comparison circuit 92 and the second comparison circuit 92a are. The pulse pattern setting circuit 233 receives the output of the state determination circuit 42 and outputs a pulse-like output signal OUT corresponding to the voltage output from the VDD terminal 221 and the sensor circuit 237 via the output circuit 236 . An output signal OUT corresponding to the characteristic signal is supplied to a light emitting section 20 (not shown) and a monitoring microcomputer (not shown).

As described above, in the optical transmitter 10d of this embodiment, the pulse pattern setting circuit 233 sets the voltage between the cell voltage VBAT of the cell 30 and the voltage output from the sensor circuit 237 (input voltage VIN). A predetermined pulse group composed of a predetermined pulse width and a predetermined number of pulses according to the range is repeatedly output for each predetermined pulse period. The optical transmitter 10d of this embodiment can periodically confirm that the input voltage VIN and the cell voltage VBAT are within a predetermined voltage range at each predetermined pulse period.

[Sixth embodiment]
The configuration of the optical transmitter 10e of the sixth embodiment will be described with reference to FIG. The same components as in the first embodiment are assigned the same numbers as in the first embodiment, and descriptions thereof are omitted. FIG. 21 is a block diagram showing an optical transmitter 10e in the sixth embodiment. The optical transmitter 10e of this embodiment is configured by adding an abnormal signal input terminal 225 to the optical transmitter 10 of the first embodiment. Also, instead of the state determination circuit 42, a state determination circuit 42b is provided. The abnormal signal input terminal 225 is connected to the state determination circuit 42b. When the abnormal signal input terminal 225 receives the active signal, the state determination circuit 42 b determines the abnormal state and outputs the abnormal state to the pulse pattern setting circuit 233 . The pulse pattern setting circuit 233 receives the output of the state determination circuit 42b and outputs a pulse-shaped output signal OUT corresponding to the abnormal state. An output signal OUT corresponding to an abnormal state is supplied to a light emitting unit 20 (not shown) and a monitoring microcomputer (not shown).

[Seventh embodiment]
The configuration of the optical transmitter 10f of the seventh embodiment will be described with reference to FIG. The same components as in the first embodiment are assigned the same numbers as in the first embodiment, and descriptions thereof are omitted. FIG. 22 is a block diagram showing an optical transmitter 10f in the seventh embodiment. The optical transmitter 10f of this embodiment has the optical transmitter 10 of the first embodiment and the light emitting section 20. FIG. The light emitting section 20 of this embodiment is connected between the VDD terminal 221 and the output terminal 223 of the optical transmitter 10 of the first embodiment. A VDD terminal 221 of the optical transmitter 10 is connected to the positive terminal of the cell 30 via a second VDD terminal 226, and a VSS terminal 222 of the optical transmitter 10 is connected to the cell 30 via a second VSS terminal 227. connected to the negative pole of Input terminal 224 is connected to the output of sensor 205 via second input terminal 28 .

The optical transmitter 10f of the present embodiment repeats a predetermined pulse group composed of a predetermined pulse width and a predetermined number of pulses according to the voltage range of the input voltage VIN from the sensor 205 at every predetermined pulse period. 20 is illuminated. The optical transmitter 10f of the present embodiment can periodically confirm that the input voltage VIN output by the sensor 205 is within a predetermined voltage range for each predetermined pulse period. In the optical transmitter 10f of the present embodiment, the light emitted from the light emitting section 20 is received by the light receiving section 80, so that the isolated communication with the cell 30 and the optical transmitter 10f is possible.

The output circuit 236 and the pulse pattern setting circuit 233 in the optical transmitter 10f are appropriately set so that the pulse pattern output by the light emitting section 20 is received by the light receiving section 80 accurately.

The output circuit 236 is set to output an appropriate output current in order to cause the light emitting section 20 to emit light with a luminous intensity that allows communication. The pulse pattern setting circuit 233 sets an appropriate pulse width in consideration of the lighting and extinguishing times required by the light emitting section 20 .

In this embodiment, the light emitting unit 20 is added to the optical transmitter 10 of the first embodiment, but the optical transmitter 10a of the second embodiment, the optical transmitter 10b of the third embodiment, The light emitting unit 20 may be added to the optical transmitter 10c of the fourth embodiment and the optical transmitter 10d of the fifth embodiment. Examples of the light emitting unit 20 include infrared light emitting diodes and visible light emitting diodes, but are not limited to these.

[Eighth embodiment]
The configuration of the optical transmitter 10g of the eighth embodiment will be described with reference to FIG. The same components as in the seventh embodiment are assigned the same numbers as in the seventh embodiment, and descriptions thereof are omitted. FIG. 23 is a block diagram showing an optical transmitter 10g in the eighth embodiment. The optical transmitter 10g of this embodiment has a configuration in which an abnormal current limiting device connection terminal 229 is provided in the optical transmitter 10f of the seventh embodiment. In the optical transmitter 10g, the source terminal of the NMOS transistor 362 of the output circuit 236 shown in FIG. 14 is connected to the abnormal current limiting device connection terminal 229 instead of the power supply VSS. The optical transmitter 10 g has a configuration in which the abnormal current limiting device 206 is connected between the abnormal current limiting device connection terminal 229 and the VSS terminal 222 . The abnormal current limiting device 206 operates to limit the current value when a current greater than or equal to a preset current value flows between the terminals.

Consider a case where the transistor of the output circuit 236 shown in FIG. 14 has a short failure in this configuration. If the PMOS transistor 361 is short-circuited, a through current flows through the abnormal current limiting device 206 via the output circuit 236 each time a pulse is output. When the current flows, the abnormal current can be limited because the operation is performed to limit the current value. The short failure of the NMOS transistor 362 can also limit the abnormal current as described above. In this embodiment, the configuration is added to the seventh embodiment, but the configuration may be added to the first to sixth embodiments. An abnormal current limiting device connection terminal 229a is provided at the source terminal of the PMOS transistor 361 of the output circuit 236, and is connected to the VDD terminal 221 through the abnormal current limiting device connection terminal 229a. A similar effect can be obtained with the configuration.

[Ninth embodiment]
The configuration of the optical transmitter 10h of the ninth embodiment of the present invention will be described with reference to FIG. The same components as in the first embodiment are assigned the same numbers as in the first embodiment, and descriptions thereof are omitted. FIG. 24 is a block diagram showing an optical transmitter 10h in the ninth embodiment. This embodiment includes a communication terminal 230 and a pulse synthesizing circuit 239 in addition to the optical transmitter 10b of the third embodiment. The optical transmitter 10h further includes a light emitting section 20 (not shown). The communication terminal 230 is configured to be connected to the output circuit 236 via the pulse synthesizing circuit 239 . The communication terminal 230 is externally daisy-chain connected to another optical transmitter, and outputs an output signal OUT from the output terminal 223 together with the monitoring status of the other optical transmitter.

The pulse synthesizing circuit 239 is installed between the pulse pattern setting circuit 233 and the output circuit 236 and outputs the sum of the signal from the pulse pattern setting circuit 233 and the signal from the communication terminal 230 to the output circuit 236 . A signal from the output circuit 236 is supplied to the light emitting unit 20 (not shown) and a monitoring microcomputer (not shown).

FIG. 25 is an example of a configuration in which the optical transmitters 10h of this embodiment are daisy-chained. The communication terminal 230 of the first optical transmitter 10h-1 of this embodiment is connected to the output terminal 223 of the second optical transmitter 10h-2. A communication terminal 230 of the second optical transmitter 10g-2 is connected to a third optical transmitter 10g-3 (not shown). The optical transmitter of this embodiment can collectively output a plurality of unit cell monitoring results from the first optical transmitter 10h-1, which is the final stage. As described above, the monitoring microcomputer (not shown) can determine the state by determining the number of subsequent pulses using the initial pulse width as a time reference. No clock synchronization is required. Similarly, the signal processing device 100 that processes the optical pulses from the light emitting unit 20 (not shown) of the optical transmitter 10h-1 determines the pulse width of the optical pulse group and the number of optical pulses to determine the state (STATE). can be determined. Therefore, a multi-voltage monitoring system can be configured easily and inexpensively while reducing the communication load of the processing circuit.

In addition, although the pulse period has been described as 1024 ms as an example, when signals from a large number of optical transmitters are combined by daisy chain connection, the pulse period is set to a long period such as 60 s (60 seconds). Collision between output signals can be avoided.

[Tenth embodiment]
The configuration of the optical transmitter 10i of the tenth embodiment will be described with reference to FIG. The same components as in the first embodiment are assigned the same numbers as in the first embodiment, and descriptions thereof are omitted. FIG. 26 is a block diagram showing the optical transmitter 10i in the tenth embodiment. This embodiment includes a communication terminal 230, a pulse determination circuit 240, and a state comparison circuit 241 in addition to the optical transmitter 10b of the third embodiment. The optical transmitter 10i further includes a light emitter 20 (not shown). The communication terminal 230 is configured to be connected to the state comparison circuit 241 via the pulse determination circuit 240 . The state comparison circuit 241 is configured to be connected to the state determination circuit 42a, the pulse determination circuit 240, and the pulse pattern setting circuit 233. FIG. The communication terminal 230 is externally daisy-chain connected to another optical transmitter, and outputs an output signal OUT from the output terminal 223 together with the monitoring status of the other optical transmitter. A signal from the output circuit 236 is supplied to the light emitting unit 20 (not shown) and a monitoring microcomputer (not shown) through the output terminal 223 .

The pulse determination circuit 240 receives a pulse signal from the communication terminal 230 and outputs a state (STATE) signal indicated by the pulse signal to the state comparison circuit 241 . The state comparison circuit 241 compares the state (STATE) signal from the state determination circuit 42a and the state (STATE) signal from the pulse determination circuit 240 according to a predetermined standard, and selects the state (STATE) signal determined to be more important. is output to the pulse pattern setting circuit 233 .

FIG. 27 is an example of a configuration in which the optical transmitters 10i of this embodiment are daisy-chained. The communication terminal 230 of the first optical transmitter 10i-1 of this embodiment is connected to the output terminal 223 of the second optical transmitter 10i-2. A communication terminal 230 of the second optical transmitter 10i-2 is connected to a third optical transmitter 10i-3 (not shown). The optical transmitter of this embodiment is capable of outputting from the optical transmitter 10i-1 the result with the highest degree of importance among the plurality of unit cell monitoring results. As described above, the monitoring microcomputer (not shown) can determine the state by determining the number of subsequent pulses using the initial pulse width as a time reference. No clock synchronization is required. Similarly, the signal processing device 100 that processes optical pulses from the light emitting unit 20 (not shown) of the optical transmitter 10i-1 judges the pulse width of the optical pulse group and the number of optical pulses to determine the state (STATE). can be determined. Therefore, a multi-voltage monitoring system can be configured easily and inexpensively while reducing the communication load of the processing circuit.

As described above, according to the optical transmitters of the various embodiments, a predetermined pulse group composed of a predetermined pulse width and a predetermined number of pulses set in advance according to the voltage state of the cell is repeated at a predetermined pulse period. Since it is output, the state of the cell voltage can be checked periodically. This makes it possible to determine whether the optical transmitter is abnormal when the output terminal of the optical transmitter is internally short-circuited with the power supply.

The embodiments described above are for facilitating understanding of the present invention, and are not for limiting interpretation of the present invention. Flowcharts, sequences, elements included in the embodiments, their arrangement, materials, conditions, shapes, sizes, and the like described in the embodiments are not limited to those illustrated and can be changed as appropriate. In addition, it is possible to replace some or all of the components shown in different embodiments or add components and combine them.

Reference Signs List 1 lithium

ion battery module

10, 10a, 10b, 10c, 10d, 10e, 10f, 10g, 10h, 10i optical transmitter 20

light emitting unit

30, 30a, 30b cell 40

control circuit

42, 42a, 42b state determination circuit 43 selector 44 look-up table 45 output terminal 50 assembled

battery

57, 59 lead wiring 60 optical waveguide 60a scattering processing 60b reflection processing 70 exterior body 80 light receiving section 90

measurement circuit

91a,

91b input terminals

92, 92a comparison circuit 95 output terminal 100 signal processing device 102 state determining unit 104 state estimating unit 110 ammeter 120 voltmeter 205 sensor 206 abnormal current limiting device 223 output terminal 224 input terminal 229 abnormal current limiting device connection terminal 230

communication terminal

301, 302

resistance circuit

303, 304 comparator 305

voltage source

306 , 307, 308, 309

Switches

310, 311, 312, 313

Resistors

314, 315, 361, 362 PMOS transistors

Claims

A lithium ion battery module including an assembled battery configured by stacking a plurality of single cells and a plurality of optical transmitters provided in the plurality of single cells,
each unit cell of the plurality of unit cells includes a positive electrode active material layer, a separator, a negative electrode active material layer, and a negative electrode current collector;
each optical transmitter of the plurality of optical transmitters corresponds to each of the cells and is powered by the corresponding cell;
each optical transmitter of the plurality of optical transmitters,
a measurement unit configured to output a characteristic signal representing characteristics of the corresponding unit cell;
a control unit configured to receive the characteristic signal and output a predetermined control signal;
a light emitting unit configured to output an optical signal corresponding to the control signal;
with
The control unit
A state determination unit that determines the state of the corresponding unit cell based on the received characteristic signal,
The light emitting unit outputs the control signal of a different pattern according to the determined state of the corresponding unit cell, and outputs the light signal of a different pattern according to the determined state of the corresponding unit cell. A lithium-ion battery module configured to control a
The lithium ion battery module according to claim 1, wherein the characteristic is the voltage of the single cell or the temperature of the single cell.
3. The lithium ion battery module according to claim 1 or 2, wherein said control section is configured to output said control signal asynchronously with control sections of other cells.
each of the plurality of optical transmitters operates with an individual internal clock, the control unit outputs the control signal at a constant cycle based on the individual internal clock, and the internal clocks are different from each other and/or 4. The lithium ion battery module according to claim 3, wherein said constant cycle is different from the constant cycle in which the control unit of said other unit cell outputs the control signal by being adjusted differently.
5. The control unit according to any one of claims 1 to 4, further configured to output a control signal having a pattern corresponding to the abnormal state in response to an external signal indicating the abnormal state from the outside. A lithium-ion battery module as described.
further comprising a light receiving unit that receives the optical signal and converts it into an electrical signal;
The lithium ion battery module according to any one of claims 1 to 5, wherein said light receiving section and said assembled battery are electrically insulated.
7. The lithium ion battery module according to claim 6, further comprising a signal processing unit configured to process the electrical signal to determine or estimate the state of each of the plurality of cells.
The lithium ion battery module according to any one of claims 1 to 7, further comprising an optical waveguide common to said plurality of optical transmitters.