Secondary battery BUSBAR

Abstract

The present invention provides a secondary battery busbar that suppresses the generation of thermoelectric power and prevents malfunctions during current sensing. [Solution] The secondary battery busbar includes a first conductive plate 110 with a first terminal hole formed therein, a second conductive plate 120 with a second terminal hole formed therein, and a resistive metal plate 130 that connects the first conductive plate and the second conductive plate to each other. The resistive metal plate is formed such that the area of ​​the joint with the first conductive plate C1 and the area of ​​the joint with the second conductive plate C2 are different from each other, according to the direction of the thermoelectric power generated by the movement of thermionic electrons.

Description

Technical Field

[0001] The present invention relates to a secondary battery bus bar, and more particularly to a secondary battery bus bar having a resistive metal plate capable of minimizing the generation of thermoelectric power.

Background Art

[0002] The content presented in this section provides background information on the present invention and does not constitute prior art.

[0003] Passive components that make up an electrical circuit are elements that only consume, store, or transmit electrical energy and do not play an active role in energy generation such as amplification. Since passive components act passively, they maintain their unique characteristics alone without an external power source. Examples of passive components include resistors, capacitors, inductors, coils, etc. Among passive components, elements that utilize "constant resistance characteristics (characteristics where resistance does not change)" are limited to resistors. Resistors can be used for various roles depending on size, material, and position.

[0004] Fixed-resistance passive components are designed with the most important characteristic being the performance of controlling a constantly flowing current and voltage. Fixed-resistance passive components are classified into fixed resistors for voltage drop to control voltage and shunt fixed resistors for current distribution to control current according to a classification method based on performance.

[0005] FIG. 1 is an exemplary diagram of a series resistance circuit and a parallel resistance circuit.

[0006] Referring to FIG. 1, the voltage can be controlled by utilizing the voltage drop through the series resistors. The current can be controlled by utilizing the current distribution through the parallel resistors. Resistors play a role in controlling the rated current and rated voltage for normal electrical operation.

[0007] The performance requirements for fixed resistors used for current and voltage control dictate that the resistor's resistance constancy and resistance invariance under environmental changes and electrical loads are the most important characteristics to manage. It has been confirmed that material and structural design methods to achieve the original performance are also being studied within this scope.

[0008] The fixed resistance of a circuit is a characteristic that fixed resistors should possess to maintain constant rated current and rated voltage. Resistivity fluctuations of fixed resistors due to electrical load or environmental factors (external disturbances such as temperature, humidity, and pressure) mean fluctuations in circuit elements and current and voltage in power distribution and power supply environments that utilize constant voltage.

[0009] Research aimed at improving the performance of fixed resistors focuses on ensuring the stability of the resistor. Fixed resistors are used in current and voltage control, current and voltage detection, and current and voltage monitoring technologies.

[0010] Sheen resistors generate a potential difference between the terminals and the resistive metal due to their structural properties and thermoelectric power, enabling precise sensing.

[0011] Figure 2 is an illustrative diagram of electron transfer due to heat.

[0012] Referring to Figure 2, when heating occurs at a specific location in a metal, electrons at that location undergo thermal vibration, and then thermionic electrons move toward the cooler direction, resulting in heat conduction. This heat conduction phenomenon creates a potential difference, much like applying an electric current across the ends of the metal.

[0013] In a sheent resistor designed with a welded joint between the resistive metal and terminal metal, the temperature of the metal rises due to the flow of current and changes in ambient temperature. When a temperature difference occurs between the resistive metal and terminal metal, a potential difference is generated due to electron movement caused by the Seebeck effect. This is because the manganin in the resistive metal rises rapidly under load, while the terminal metals at both ends play a role in dissipating heat generated in the resistive metal by conducting it. This resulting thermoelectric force can cause malfunctions or sensing errors in the sheent's primary function of current sensing.

[0014] Figure 3 is an example of trimming using conventional technology.

[0015] Referring to Figure 3, a secondary battery busbar is depicted. The trimming is located in the center of the resistive metal plate where the load is concentrated.

[0016] As a technology related to the present invention, a method for manufacturing a dissimilar metal busbar disclosed in the Registered Patent Publication of the Republic of Korea includes a dissimilar metal joining process, a material preparation process, a tension control process, a shape correction process, a cutting process, and a soft etching process. This related technology concerns the manufacturing process, and the present invention is distinguished from the other invention in that it is a secondary battery busbar having a resistive metal plate that can minimize the generation of thermoelectric power. [Prior art documents] [Patent Documents]

[0017] [Patent Document 1] Republic of Korea Registered Patent No. 10-2669076 (Published May 24, 2024) [Overview of the project] [Problems that the invention aims to solve]

[0018] The problem that this invention aims to solve is to provide a secondary battery busbar that can minimize the generation of thermoelectric power.

[0019] The problem to be solved by the present invention is to provide a secondary battery bus bar having a fixed resistance value.

[0020] The problem to be solved by the present invention is not limited to the problems mentioned above, and other problems not mentioned can also be clearly understood by those skilled in the art from the following description.

Means for Solving the Problem

[0021] In order to achieve the above object, according to an embodiment based on the technical idea of the present invention,

[0022] A secondary battery bus bar is disclosed, which includes a first conductive plate having a first terminal hole, a second conductive plate having a second terminal hole, and a resistance metal plate connecting the first conductive plate and the second conductive plate to each other. The resistance metal plate is formed such that the area of the joint with the first conductive plate and the area of the joint with the second conductive plate are different according to the direction of the thermoelectromotive force generated by the movement of hot electrons.

[0023] Further, the secondary battery bus bar is characterized in that the resistance metal plate is formed such that the height of the joint with the first conductive plate and the height of the joint with the second conductive plate are different.

[0024] Further, when the direction of the thermoelectromotive force is from the joint with the first conductive plate to the joint with the second conductive plate, the secondary battery bus bar is characterized in that the joint with the first conductive plate is formed wider than the joint with the second conductive plate.

[0025] Further, when the direction of the thermoelectromotive force is from the joint with the first conductive plate to the joint with the second conductive plate, the secondary battery bus bar is characterized in that the joint with the first conductive plate is formed wider than the joint with the second conductive plate.

[0026] Specific matters of other embodiments are included in "Specific Content for Implementing the Invention" and the attached "Drawings".

[0027] The advantages and / or features of the present invention, and the method of achieving them, will become clear by referring to the various embodiments described in detail hereinafter together with the attached drawings.

[0028] However, the present invention is not limited only to the configurations of the embodiments disclosed below, and can be implemented in various different forms. Each embodiment disclosed in this specification is provided to make the disclosure of the present invention complete and to fully inform those with ordinary knowledge in the technical field to which the present invention pertains of the scope of the present invention. It should be understood that the present invention is defined only by the scope of each claim of the claims.

Effect of the Invention

[0029] According to the present invention, the generation of thermoelectric power in the secondary battery busbar is suppressed, and malfunction during current sensing is prevented.

[0030] In addition, precise current measurement is possible based on the fixed resistance value of the secondary battery busbar.

[0031] The effects obtained by the secondary battery busbar according to the technical idea of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those with ordinary knowledge in the technical field to which the present invention pertains from the following description.

Brief Description of the Drawings

[0032] [Figure 1] Figure 1 is an exemplary diagram of a series resistance circuit and a parallel resistance circuit. [Figure 2] Figure 2 is an exemplary diagram of the movement of electrons due to heat. [Figure 3] Figure 3 is an exemplary diagram of resistance metal plate trimming according to the prior art. [Figure 4] Figure 4 is an exemplary diagram of a secondary battery busbar. [Figure 5] Figure 5 is an exemplary diagram of electron movement occurring in a secondary battery busbar. [Figure 6] Figure 6 is an exemplary diagram of thermoelectric power according to the alloy ratio. [Figure 7] Figure 7 is an illustrative diagram of a secondary battery busbar having a resistive metal plate according to one embodiment of the present invention. [Figure 8] Figure 8 is an illustrative diagram of the thermoelectric power with respect to the shape of a resistive metal plate according to one embodiment of the present invention. [Figure 9] Figure 9 is an illustrative diagram of trimming a resistive metal plate according to one embodiment of the present invention. [Figure 10] Figure 10 is an example diagram of a secondary battery busbar for improving frequency stability. [Figure 11] Figure 11 is an illustrative diagram showing the rate of resistance change with frequency for a secondary battery busbar in the prior art and according to the present invention. [Figure 12] Figure 12 is an illustrative diagram of a thermoelectric power measurement method according to one embodiment of the present invention. [Figure 13] Figure 13 is a specific example diagram illustrating the thermoelectric power measurement method shown in Figure 11. [Figure 14] Figure 14 is a circuit diagram for a thermoelectric power measurement method according to one embodiment of the present invention. [Figure 15] Figure 15 is an illustrative diagram of the thermoelectric power measurement position in a thermoelectric power measurement method according to one embodiment of the present invention. [Modes for carrying out the invention]

[0033] Before describing the present invention in detail, it should be understood that the terms and words used herein should not be interpreted in their general or dictionary sense, and that the inventors of the present invention may appropriately define and use the concepts of various terms in order to best describe their invention, and furthermore, these terms and words should be interpreted in a sense and concept that is consistent with the technical idea of ​​the present invention.

[0034] In other words, the terms used herein are used to describe preferred embodiments of the invention and are not intended to specifically limit the scope of the invention. It should be understood that these terms are defined in consideration of the various possibilities of the invention.

[0035] Furthermore, in this specification, singular expressions may include plural expressions unless explicitly indicated otherwise in context, and similarly, plural expressions may retain a singular meaning.

[0036] Throughout this specification, when a component is described as "containing" another component, unless otherwise stated, it does not mean that any other component is excluded, but rather that it may contain any other component.

[0037] Furthermore, when it is stated that a component is "located inside or connected to" another component, it is possible that this component is directly connected to or in contact with the other component. Even if it is installed isolated at a certain distance, there may be a third component or means for fixing or connecting the component to the other component, and it should be understood that a description of this third component or means may be omitted.

[0038] On the other hand, if it is stated that one component is "directly connected" or "directly in contact" with another component, it should be understood that there is no third component or means.

[0039] Similarly, other expressions describing the relationships between each component, such as "between" and "immediately between," or "adjacent to" and "directly adjacent to," should be interpreted in the same way.

[0040] Furthermore, when terms such as "one side," "the other side," "one side," "the other side," "first," and "second" are used in this specification, it is important to understand that these terms are used to clearly distinguish each component from other components, and that the meaning of the component in question is not limited by these terms.

[0041] Furthermore, where position-related terms such as “up,” “down,” “left,” and “right” are used in this specification, they should be understood to indicate the relative position in the drawing with respect to the respective component, and these position-related terms should not be understood to indicate an absolute position unless an absolute position is specified for those positions.

[0042] Furthermore, in this specification, when specifying the reference numeral for each component in each drawing, the same component will have the same reference numeral even if it is shown in other drawings; in other words, the same reference numeral throughout the specification will indicate the same component.

[0043] The sizes, positions, and relationships of the components constituting the present invention in the drawings attached to this specification may be exaggerated, reduced, or omitted in part in order to clearly convey the concept of the present invention or for the sake of explanatory convenience, and therefore the proportions and scales may not be precise.

[0044] Furthermore, in describing the present invention below, detailed explanations of configurations that may unnecessarily obscure the gist of the invention, such as prior art and other known technologies, may be omitted.

[0045] Hereinafter, embodiments of the present invention will be described in detail with reference to the relevant drawings.

[0046] In the secondary battery busbar 100 according to the first embodiment of the present invention, the thermoelectric voltage generated in the resistive metal plate 130 can be suppressed by balancing through the design of the resistive metal plate 130.

[0047] Thermoelectromotive force is the electric force generated between two metals joined at two points, due to the Seebeck effect, when there is a temperature difference between the two junctions.

[0048] Figure 4 is an example diagram of a secondary battery busbar.

[0049] Referring to Figure 4, the actual configuration of the secondary battery busbar 100 is shown. The first conductive plate 110 and the second conductive plate 120 that make up the secondary battery busbar 100 are 99.97% copper and have pure copper terminals. The resistive metal plate 130, which corresponds to the sheent resistor, is an alloy of copper, manganese, and nickel, i.e., manganin.

[0050] The connection point between the first conductive plate 110 and the resistive metal plate 130 is the first joint C1. The connection point between the resistive metal plate 130 and the second conductive plate 120 is the second joint C2. The first joint C1 and the second joint C2 correspond to two contact points where two different metals are connected and a thermoelectric effect occurs.

[0051] Figure 5 is an illustrative diagram of electron transfer occurring in a secondary battery busbar.

[0052] Referring to Figure 5, when current is applied to the secondary battery busbar, the temperature of the resistive metal plate 130 rises due to its high resistance. After the current is stopped, the rise in temperature causes electrons from the resistive metal plate 130 to move to the terminals at both ends.

[0053] Generally, the amount of electron transfer due to a temperature gradient decreases as the temperature coefficient of resistance decreases and the metals have a relatively low coefficient of resistance and a high degree of similarity between the terminals and the metal. In other words, when a load is applied, the more similar the resistance and material type of the conductive plates 110 and 120 and the resistive metal plate 130 are, the smaller the temperature difference between the conductive plates 110 and 120 and the resistive metal plate 130 becomes, resulting in a lower thermoelectric force moving to both ends.

[0054] However, the fixed resistance required for use as a sheent current sensor is met more readily when the alloy content is high. Conductive plates, which provide lossless power conduction and heat dissipation, meet the requirements in a pure metal state. Therefore, due to the conflicting properties of the material improvement methods, it can be concluded that reducing the thermoelectric power in the resistive metal plate 130 is difficult to achieve through improvement of alloy material design.

[0055] Figure 6 is an example diagram showing the thermoelectric power based on the alloy ratio.

[0056] Referring to Figure 6, the temperature-dependent distribution of thermoelectric power in the resistance metal plates 130 made of Cu-45Ni-2Mn and Cu-5Ni material is shown. It can be seen that when the alloy content of the resistance metal plate 130 is low, the increase in thermoelectric power with temperature is gradual, but when the alloy content of the resistance metal plate 130 is high, the increase in thermoelectric power changes rapidly.

[0057] The potential difference between the two junctions is due to the fact that the manganin in the resistive metal plate 130 heats up quickly under load, and the conductive plates 110 and 120 at both ends conduct and dissipate the heat generated in the resistive metal plate 130. This thermoelectric voltage can cause malfunctions or sensing errors in current sensing, which is the main application of the resistive metal plate 130.

[0058] Referring to Figure 6, the temperature coefficient of resistance is shown as a result of thermoelectric power tests for the largest and smallest alloys. A lower temperature coefficient of resistance tends to result in a more fixed resistance.

[0059] In contrast, the present invention does not minimize thermoelectric power by adjusting the materials to increase the similarity between the conductive plates 110, 120 and the resistive metal plate 130, but rather by adjusting the amount of heat transfer to the conductive plates 110, 120 to adjust the movement of thermionic electrons, thereby reducing thermoelectric power. The invention also proposes a method for accurately measuring thermoelectric power.

[0060] Figure 7 is an illustrative diagram of a secondary battery busbar having a resistive metal plate according to one embodiment of the present invention.

[0061] Referring to Figure 7, the structural design of the resistive metal plate 130 is shown, which adjusts the contact area between the conductive plates 110 and 120 and the resistive metal plate 130 in order to minimize the thermoelectric power.

[0062] After an electrical or environmental load is applied, thermionic electrons move from the central resistive metal, whose temperature rises relatively compared to the terminal metal, to both ends.

[0063] At this time, when measuring the contact pressure using a nanovoltage meter, even if no current flows through the resistive metal plate 130, a voltage of several μV to mV is measured, and its directionality can be confirmed as a (+) or (-) value depending on the position of the measurement probe.

[0064] Referring to Figure 7, the thermoelectric voltage (EMV) can be minimized by trimming the area in contact with the terminals relative to the direction of the EEVS measured in a sheent environment. For example, to activate electron flow in the opposite direction to the direction in which the EEVS is generated, the area of ​​the junction in the opposite direction may be designed to be larger. The difference in area between junctions C1 and C2 can be achieved by adjusting the height of the junctions. In the example diagram on the left of Figure 7, when the EEVS is generated in the cathode direction, the EEVS is suppressed when the area of ​​the first junction C1 in the anode direction is larger than the area of ​​the second junction C2. Conversely, in the example diagram on the right, when the EEVS is generated in the anode direction, the EEVS is suppressed when the area of ​​the first junction C1 in the anode direction is smaller than the area of ​​the second junction C2.

[0065] Figure 8 is an illustrative diagram of the thermoelectric power with respect to the shape of a resistive metal plate according to one embodiment of the present invention.

[0066] Referring to Figure 8, the shape of the resistive metal plate 130, that is, the distribution of thermoelectric power with respect to the area of ​​the junction between the resistive metal plate 130 and the conductive plates 110 and 120, is depicted. It can be seen that as the height of the first junction C1 between the conductive plates 110 and 120 and the resistive metal plate 130 decreases, the distribution of thermoelectric power with respect to temperature decreases.

[0067] The secondary battery busbar 100 according to the second embodiment of the present invention has its thermoelectric power suppressed through the post-processing of the resistive metal plate 130, and can have a precise resistance value.

[0068] Referring again to Figure 3, the final step in manufacturing the secondary battery busbar as a final product through existing press die processing is to perform fine trimming on the resistive metal plate. The method for achieving a precise resistance value through fine trimming is to place the trimming at the center of the secondary battery busbar's length 10, on the side portion of the resistive metal plate. Such trimming positions result in narrowing the current lines at the center 20 of the resistive metal plate where the maximum load occurs in the Shent structure. Consequently, the temperature at the center of the resistive metal plate may rise locally, potentially causing fluctuations in resistance stability.

[0069] It is necessary to design a resistive metal plate 130 that suppresses the generation of thermoelectric power and maintains the current-carrying line area in the load-concentrated area.

[0070] Figure 9 is an illustrative diagram of trimming a resistive metal plate according to one embodiment of the present invention.

[0071] Referring to Figure 9, the resistive metal plate 130 has both a shape for achieving a precise resistance value and a shape for suppressing thermoelectric power generation. The area of ​​the first joint C1 where the resistive metal plate 130 and the first conductive plate 110 are connected and the area of ​​the second joint C2 where the resistive metal plate 130 and the second conductive plate 120 are connected are different, and trimming T is applied to make it narrower or wider depending on the direction of the thermoelectric power, so the resistive metal plate 130 is trapezoidal. In other words, in the example diagram on the left, when thermoelectric power is generated from the cathode to the anode, the area of ​​C2 must be greater than the area of ​​C1 in order to allow more electrons to flow in the opposite direction. Conversely, in the example diagram on the right, when thermoelectric power is generated from the anode to the cathode, the area of ​​C1 must be greater than the area of ​​C2 in order to allow more electrons to flow in the opposite direction.

[0072] After the resistive metal plate 130 is manufactured, the final trimming T position may be moved from the upper center of the resistive metal plate 130 to the contact surface in order to achieve a precise resistance configuration and thermoelectric voltage balancing. In this way, with respect to thermoelectric voltage in either the negative or positive direction, the secondary battery busbar 100 according to one embodiment of the present invention has improved performance in terms of precise resistance value and thermoelectric voltage suppression through the design of the trapezoidal resistive metal plate 130.

[0073] The secondary battery busbar 100 according to the third embodiment of the present invention has improved frequency stability due to the fine connection with a small contact area between the conductive plates 110, 120 and the resistive metal plate 130.

[0074] Unlike DC power supplies, measuring AC power supplies can result in discrepancies or errors between theoretical and actual measured values ​​due to the skin effect caused by frequency. To address this problem, there are two methods: minimizing the wire diameter using multiple core wires, as is done with power cables and power transmission lines, and adjusting the plate thickness in the current-carrying line.

[0075] Figure 10 is an example diagram of a secondary battery busbar for improving frequency stability.

[0076] Referring to Figure 10, in order to achieve thermoelectric balancing, the resistive metal plate 130, which has a small contact area (is made thin) with the conductive plates 110 and 120, does not change resistance up to the AC power sensing frequency of 60 Hz, and the performance of fixing the resistance value with respect to frequency is improved compared to conventional sheen designs. Furthermore, to further improve the resistance fixing performance with respect to frequency, as shown in Figure 10, the improved resistance fixing performance with respect to frequency can be achieved by connecting multiple resistive metal pieces with a thickness of 0.068 mm or less in parallel to the resistive metal plate 130 which has an existing thermoelectric balancing design.

[0077] Figure 11 is an illustrative diagram showing the rate of resistance change with respect to frequency for a secondary battery busbar of the prior art and according to the present invention.

[0078] Referring to Figure 11, the resistance change rate with respect to frequency for each sheent, i.e., the structure of the resistive metal plate 130, is depicted. In the conventional method, the resistance change rate is highest as the frequency increases. Furthermore, the resistance change rate of the resistive metal plate 130 in the third embodiment appears to be lower than that of the resistive metal plate 130 in the first embodiment.

[0079] Through the thermoelectric power measurement method S100 using a secondary battery busbar according to the fourth embodiment of the present invention, the thermoelectric power at both ends of the resistive metal plate contained in the secondary battery busbar can be accurately measured.

[0080] Figure 12 is an illustrative diagram of a thermoelectric power measurement method according to one embodiment of the present invention.

[0081] Referring to Figure 12, the thermoelectric power measurement method S100 can be configured to include a step S110 of applying a primary current to the secondary battery busbar, a step S120 of applying a secondary current to the secondary battery busbar, and a step S130 of measuring the thermoelectric power of the secondary battery busbar. Here, the direction of the primary current and the direction of the secondary current are opposite to each other.

[0082] In addition to its function of electrically connecting battery cells, the secondary battery busbar has a sensing function for measuring current and voltage. The secondary battery busbar includes two conductive plates, namely a first conductive plate 110 and a second conductive plate 120, and a resistive metal plate 130. The resistive metal plate 130 has junctions at both ends, namely a first junction C1 and a second junction C2, to which the first conductive plate 110 and the second conductive plate 120 are connected.

[0083] Figure 13 is a specific example diagram of the thermoelectric power measurement method shown in Figure 11.

[0084] Referring to Figure 13, the step S110 for applying the primary current can be configured to include a step S111 for applying current in one direction and a step S112 for measuring the intermediate temperature. Although not shown in Figure 13, the flow of the primary current may be interrupted when the temperature of the resistive metal plate 130 reaches half of the target temperature. The target temperature is the temperature at which the thermoelectric power is to be measured.

[0085] For example, if the target temperature is 60 degrees Celsius, the primary current may be applied until the temperature reaches 30 degrees Celsius, which is half the target temperature. The temperature may also be measured using non-contact thermometers, such as infrared cameras.

[0086] When measuring thermoelectric power using the temperature rise of a resistive metal plate 130 due to an electrical load, a phenomenon occurs where the temperature of the heat-generating part rises further and the temperature of the heat-absorbing part falls further due to the Peltier effect between dissimilar metals, requiring a change in the direction of current flow.

[0087] The step S120 for applying a secondary current can be configured to include a step S121 for applying a secondary current in the opposite direction to the primary current flow, a step S122 for measuring the target temperature, and a step S123 for stopping the current flow at the target temperature. Measuring the target temperature and stopping the current flow can be done simultaneously.

[0088] A secondary current may be applied to the secondary battery busbar 100 from 30 degrees Celsius. The direction of current flow can be changed by switching the power supply direction. When the temperature of the resistive metal plate reaches 60 degrees Celsius, the current flow is stopped.

[0089] In step S130, where the current is measured, a nanovoltage meter may be used when the temperature of the resistive metal plate reaches 60 degrees Celsius. The thermoelectric voltage may be measured with the probe of the nanovoltage meter in contact with the first conductive plate 110 and the second conductive plate 120, which are bonded to the resistive metal plate.

[0090] Referring to Figure 13, the center corresponds to the resistive metal plate 130. The center is located inside the chamber, and within the chamber, the nanovoltage meter contacts a conductive plate connected to the resistive metal plate 130. The control unit has the function of controlling the start and interruption of current flow, the conversion of current direction, and non-contact temperature measurement by switching.

[0091] Figure 14 is a circuit diagram for a thermoelectric power measurement method according to one embodiment of the present invention.

[0092] Referring to Figure 14, in the upper and lower circuits, the first conductive plate 110 and the resistive metal plate 130 can be electrically connected at the first joint C1, and the resistive metal plate 130 and the second conductive plate 120 can be electrically connected at the second joint C2.

[0093] A power supply can be connected to the first conductive plate 110 and the second conductive plate 120. The power supply includes a first power supply E1 and a second power supply E2. In the upper and lower circuits, the first power supply E1 and the second power supply E2 have opposite polarities.

[0094] Due to the Peltier effect between the two metals, the temperature of the second joint C2, which is the heat-generating part, gradually rises, while the temperature of the first joint C1, which is the heat-absorbing part, gradually decreases. Therefore, a change in the direction of current flow is necessary. The point at which the direction of current flow is changed is when the measured temperature reaches an intermediate temperature, which is half of the target temperature.

[0095] The upper circuit may be energized in the primary current direction, while the lower circuit may be energized in the secondary current direction. The direction of energization can be changed by using switching to reverse the polarity of the first power supply E1 and the second power supply E2.

[0096] To measure minute electron transfers exhibiting voltages of a few μV to mV, it is crucial to minimize electron transfer due to contact conductivity, such as probe contact or thermocouple contact, and therefore, test procedures for this purpose need to be defined.

[0097] Figure 15 is an illustrative diagram of the thermoelectric power measurement location in a thermoelectric power measurement method according to one embodiment of the present invention.

[0098] Referring to Figure 15, the location where the thermoelectric power is measured on the resistive metal plate 130 is depicted. The thermoelectric power is measured not on the resistive metal plate 130, but on the first conductive plate 110 and the second conductive plate 120 connected to the resistive metal plate 130, and points near the first joint C1 and points near the second joint C2 can be used as measurement locations.

[0099] Thus, according to one embodiment of the present invention, the generation of thermoelectric power in the secondary battery busbar is suppressed, and malfunctions during current sensing can be prevented.

[0100] Furthermore, precise current measurement is possible based on the fixed resistance value of the secondary battery busbar.

[0101] While we have described some desirable embodiments of the present invention as examples, the descriptions of the various embodiments in the "Specific Details for Carrying Out the Invention" section are illustrative, and a person with ordinary skill in the art to which the present invention belongs will understand from the above description that they can carry out the present invention in various modified forms or in an equivalent form.

[0102] Furthermore, since the present invention can be realized in various other forms, it should be understood that the present invention is not limited by the above description, and that the above description is provided only to complete the disclosure of the present invention and to fully inform those who are ordinary skill in the art to which the present invention pertains, and that the present invention is defined only by the claims.

Claims

1. The device includes a first conductive plate having a first terminal hole formed therein, a second conductive plate having a second terminal hole formed therein, and a resistive metal plate that electrically connects the first conductive plate and the second conductive plate to each other. A secondary battery busbar characterized in that the resistive metal plate is formed such that the area of ​​the joint with the first conductive plate and the area of ​​the joint with the second conductive plate are different from each other, according to the direction of the thermoelectric power generated by the movement of thermionic electrons.

2. The secondary battery busbar according to claim 1, characterized in that the resistive metal plate is formed such that the height of the joint with the first conductive plate and the height of the joint with the second conductive plate are different from each other.

3. The secondary battery busbar according to claim 1, characterized in that, when the direction of the thermoelectric power is from the joint with the first conductive plate to the joint with the second conductive plate, the joint with the first conductive plate is formed to be wider than the joint with the second conductive plate.

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