Patent Description:
Recently, there is dramatically growing demand for portable electronic products such as laptop computers, video cameras and mobile phones, and with the intense development of electric vehicles, accumulators for energy storage, robots and satellites, many studies are being made on high performance secondary batteries that can be recharged repeatedly.

Currently, commercially available secondary batteries include nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, lithium secondary batteries and the like, and among them, lithium secondary batteries have little or no memory effect, and thus they are gaining more attention than nickel-based secondary batteries for their advantages of free charging and discharging, a very low self-discharge rate and high energy density.

The lithium secondary battery mainly uses lithium-based oxide and a carbon material for a positive electrode active material and a negative electrode active material respectively. The lithium secondary battery includes an electrode assembly including a positive electrode plate and a negative electrode plate coated respectively with the positive electrode active material and the negative electrode active material with a separator interposed between, and a packaging material, i.e., a battery case hermetically sealed to receive the electrode assembly therein together with an electrolyte solution.

In general, lithium secondary batteries may be classified into can-type secondary batteries in which an electrode assembly is embedded in a metal can and pouch-type secondary batteries in which an electrode assembly is embedded in a pouch of an aluminum laminate sheet, according to the shape of the packaging material. These secondary batteries are usually manufactured by receiving the electrode assembly in the packaging material, and in this state, injecting an electrolyte solution, and sealing the packaging material.

More recently, with the extended application range of pouch-type secondary batteries, pouch-type secondary batteries are being widely used in small portable devices including smart phones, as well as medium- and large-scale devices such as electric vehicles including hybrid vehicles or energy storage systems.

In the case of a secondary battery, as the usage period increases, the performance degrades compared to initial state. Additionally, performance degradation estimation of the secondary battery is said to be State Of Health (SOH) estimation of the secondary battery, and the SOH of the secondary battery is an important factor in determining when to replace the secondary battery.

Additionally, the secondary battery may differ in degradation for each secondary battery depending on environments in which the secondary battery is manufactured and used. Additionally, in the case of a battery pack including a plurality of secondary batteries, it is necessary to accurately estimate the life of each secondary battery as the secondary batteries degrade. Typically, a Battery Management System (BMS) is required to accurately estimate the SOH of each secondary battery provided in the battery pack, and based on this, operate the battery pack efficiently.

Prior art is disclosed in <CIT>, <CIT>, <CIT> and <CIT>.

The present disclosure is designed under the background of the related art as described above, and therefore the present disclosure is directed to providing an improved apparatus for effectively estimating the SOH of a secondary battery and a battery pack including the same.

These and other objects and advantages of the present invention will be understood by the following description and will be apparent from the embodiments of the present invention as defined in the appended claims.

An apparatus according to an aspect of the present invention is defined in independent claim <NUM>. Such an apparatus is for estimating a state of a secondary battery, connectable to a positive electrode lead, a negative electrode lead, a first measuring lead and a second measuring lead included in the secondary battery. The apparatus includes a terminal case including a plurality of inner terminals, each of the plurality of inner terminals configured to be contactable with the positive electrode lead, the negative electrode lead, the first measuring lead, or the second measuring lead on a first surface of the terminal case, and a plurality of outer terminals configured to be respectively electrically connectable to the plurality of inner terminals on a second surface facing the first surface of the terminal case; a voltage measuring unit configured to be electrically connectable to at least two of the plurality of outer terminals, and measure a potential difference between the first measuring lead and the second measuring lead; and a control unit configured to estimate a state of health of the secondary battery using the potential difference between the first measuring lead and the second measuring lead measured by the voltage measuring unit.

The plurality of inner terminals include inner charging/discharging terminals. The inner charging/discharging terminals include a first inner positive electrode terminal configured to be connectable to each of the first measuring lead, the second measuring lead and the positive electrode lead, and a first inner negative electrode terminal configured to be connectable to the negative electrode lead.

The plurality of inner terminals may include an inner measuring terminals. The inner measuring terminals may include a second inner positive electrode terminal configured to be connectable to the positive electrode lead, a second inner negative electrode terminal configured to be connectable to the negative electrode lead, a first inner measuring terminal configured to be connectable to the first measuring lead, and a second inner measuring terminal configured to be connectable to the second measuring lead.

The plurality of outer terminals may include an outer positive electrode terminal electrically connectable to each of the first inner positive electrode terminal and the second inner positive electrode terminal, and an outer negative electrode terminal electrically connectable to each of the first inner negative electrode terminal and the second inner negative electrode terminal.

The plurality of outer terminals may include a first outer measuring terminal electrically connectable the first inner measuring terminal, and a second outer measuring terminal electrically connectable to the second inner measuring terminal.

The apparatus may further include a switching element configured to selectively change the electrical connection between each of the negative electrode lead, the first measuring lead, the second measuring lead and the positive electrode lead, and the plurality of inner terminals.

The switching element may include a normal mode circuit and a measurement mode circuit. The normal mode circuit may be configured to electrically connect each of the negative electrode lead, the first measuring lead, the second measuring lead and the positive electrode lead to the inner charging/discharging terminal. The measurement mode circuit may be configured to electrically connect each of the negative electrode lead, the first measuring lead, the second measuring lead and the positive electrode lead to the inner measuring terminal.

A battery pack according to another aspect of the present invention includes the above-described apparatus for estimating the state of the secondary battery.

According to the apparatus in accordance with the present invention, there is provided a terminal case equipped with a plurality of terminals to accurately measure a potential difference between two electrode plates included in a secondary battery.

Particularly, there is an advantage - it is possible to estimate the SOH of the secondary battery rapidly in a simple and convenient manner while the secondary battery is being used in normal condition, by selectively running a normal mode in which the secondary battery is charged/discharged and a measurement mode in which the SOH of the secondary battery is estimated.

The present disclosure may have a variety of other effects, and these and other effects of the present disclosure can be understood by the following description and will be apparent from the embodiments of the present disclosure.

The accompanying drawings illustrate preferred embodiments of the present disclosure, and together with the following detailed description, serve to provide a further understanding of the technical aspects of the present disclosure. However, the present disclosure is not to be construed as being limited to the drawings.

<FIG> is a schematic exploded perspective view showing the configuration of a secondary battery according to an embodiment of the present disclosure, and <FIG> is an assembled perspective view of <FIG>.

Referring to <FIG> and <FIG>, the secondary battery <NUM> may be a pouch-type secondary battery, and includes a packaging material <NUM>, an electrode assembly <NUM>, a first electrode lead <NUM>, a second electrode lead <NUM>, a first measuring lead <NUM> and a second measuring lead <NUM>.

The packaging material <NUM> may have a concave internal space, and the electrode assembly <NUM> and an electrolyte solution may be received in the internal space.

The packaging material <NUM> may include an upper pouch <NUM> and a lower pouch <NUM>, and in this case, the concave internal space may be formed in both the upper pouch <NUM> and the lower pouch <NUM> as shown in the drawing.

Additionally, the packaging material <NUM> may be formed by sealing the outer periphery of the upper pouch <NUM> and the lower pouch <NUM>. That is, each of the upper pouch <NUM> and the lower pouch <NUM> may have a sealing part S at the edges of the internal space, and the internal space of the packaging material <NUM> may be hermetically closed by sealing the sealing part S by heat fusion.

The electrode assembly <NUM> includes at least one separator, a plurality of first electrode plates <NUM>, a plurality of second electrode plates <NUM>, a plurality of first electrode tabs <NUM>, a plurality of second electrode tabs <NUM>, a first measuring electrode plate <NUM>, a second measuring electrode plate <NUM>, a first measuring tab <NUM> and a second measuring tab <NUM>.

The first electrode plate <NUM> may be a positive electrode plate and the second electrode plate <NUM> may be a negative electrode plate. In this case, the first electrode tab <NUM> may be referred to as a positive electrode tab and the second electrode tab <NUM> may be referred to as a negative electrode tab.

Alternatively, the first electrode plate <NUM> may be a negative electrode plate and the second electrode plate <NUM> may be a positive electrode plate. In this case, the first electrode tab <NUM> may be referred to as a negative electrode tab and the second electrode tab <NUM> may be referred to as a positive electrode tab.

The plurality of first electrode plates <NUM> and the plurality of second electrode plates <NUM> stacked in an alternating manner with the separator interposed between is received in the internal space of the packaging material <NUM>. More specifically, the electrode assembly <NUM> may be formed by stacking the plurality of first electrode plates <NUM> and the plurality of second electrode plates <NUM> in an alternating manner.

The electrode assembly <NUM> may include the first electrode plate <NUM> and the second electrode plate <NUM> stacked with their wide surfaces facing each other with respect to the separator interposed between. That is, the electrode assembly <NUM> may include the first electrode plate <NUM> and the second electrode plate <NUM> stacked in an alternating manner with the separator interposed between, and the first electrode plate <NUM> and the second electrode plate <NUM> are spaced a predetermined distance apart from each other by the separator. Additionally, the first electrode plate <NUM> and the second electrode plate <NUM> are formed by applying an active material slurry to a current collector, and the slurry may be generally formed by shaking a particulate active material, an auxiliary conductor, a binder and a plasticizer with an addition of solvents.

The first electrode tab <NUM> and the second electrode tab <NUM> extend from the plurality of first electrode plates <NUM> and the plurality of second electrode plates <NUM> respectively. More specifically, the first electrode plate <NUM> and the second electrode plate <NUM> provided in the electrode assembly <NUM> may have respectively the first electrode tab <NUM> and the second electrode tab <NUM> in a non-coated region where the active material is not coated. For example, the first electrode tab <NUM> and the second electrode tab <NUM> may extend out of the electrode plates <NUM>, <NUM> respectively, and may be formed by cutting the electrode plate or attaching a metal plate of a same or different material to the electrode plate.

The first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may have the same polarity. For example, both the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may have the same polarity as any one of the first electrode plate <NUM> and the second electrode plate <NUM>.

Each of the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be formed by applying a positive electrode active material to the surface of an aluminum current collector. Alternatively, each of the first measuring electrode plate and the second measuring electrode plate may be formed by applying a negative electrode active material to the surface of an aluminum current collector.

Particularly, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> are provided at the position of the first electrode plate <NUM> or the second electrode plate <NUM> in place of at least one electrode plate of the plurality of first electrode plates <NUM> and the plurality of second electrode plates <NUM>.

The first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided at the position of the first electrode plate <NUM> or the second electrode plate <NUM> in place of at least one first electrode plate <NUM> or second electrode plate <NUM> of the plurality of first electrode plates <NUM> and the plurality of second electrode plates <NUM> stacked in an alternating manner in up-down direction.

For example, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided at the position of the first electrode plate <NUM> in place of the first electrode plate <NUM>.

Alternatively, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided at the position of the second electrode plate <NUM> in place of the second electrode plate <NUM>.

The first measuring tab <NUM> and the second measuring tab <NUM> are electrically connected to the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> respectively. Here, the first measuring tab <NUM> and the second measuring tab <NUM> may extend from the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> respectively. More specifically, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> provided in the electrode assembly <NUM> may have respectively the first measuring tab <NUM> and the second measuring tab <NUM> in the non-coated region where the active material is not coated. For example, the first measuring tab <NUM> and the second measuring tab <NUM> may extend out of the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> respectively. The first measuring tab <NUM> may be formed by cutting the first measuring electrode plate <NUM> or attaching a metal plate of a same or different material to the first measuring electrode plate <NUM>. The second measuring tab <NUM> may be formed by cutting the second measuring electrode plate <NUM> or attaching a metal plate of a same or different material to the second measuring electrode plate <NUM>.

One end of the first electrode lead <NUM> electrically contacts with the plurality of first electrode tabs <NUM>. The other end of the first electrode lead <NUM> is exposed outside of the packaging material <NUM>. Additionally, a portion between one end and the other end of the first electrode lead <NUM> is inserted into the packaging material <NUM>. More specifically, the plurality of first electrode tabs <NUM> extending out of each of the plurality of first electrode plates <NUM> may be connected to the first electrode lead <NUM> in contact with each other. The connection between the plurality of first electrode tabs <NUM> and/or the connection between the first electrode tab <NUM> and the first electrode lead <NUM> may be carried out by a welding process. For example, as shown in the configuration of <FIG>, the first electrode lead <NUM> may be directly connected to the plurality of first electrode tabs <NUM> extending out of the plurality of first electrode plates <NUM>.

Additionally, the first electrode lead <NUM> may be interposed between the upper pouch <NUM> and the lower pouch <NUM> such that parts of the first electrode lead <NUM> may be disposed in the internal space of the packaging material <NUM>. Additionally, the other parts of the first electrode lead <NUM> may be exposed outside of the packaging material <NUM>. For example, as shown in the configuration of <FIG>, the first electrode lead <NUM> may extend in the outward direction of the packaging material <NUM> with the parts of the first electrode lead <NUM> exposed outside of the packaging material <NUM>.

One end of the second electrode lead <NUM> electrically contacts with the second electrode tab <NUM>. The other end of the second electrode lead <NUM> is exposed outside of the packaging material <NUM>. Additionally, a portion between one end and the other end of the second electrode lead <NUM> is inserted into the packaging material <NUM>. More specifically, the plurality of second electrode tabs <NUM> extending out of each of the plurality of second electrode plates <NUM> may be connected to the second electrode lead <NUM> in contact with each other. The connection between the plurality of second electrode tabs <NUM> and/or the connection between the second electrode tab <NUM> and the second electrode lead <NUM> may be carried out by a welding process. For example, as shown in the configuration of <FIG>, the second electrode lead <NUM> may be directly connected to the plurality of second electrode tabs <NUM> extending out of the plurality of second electrode plates <NUM>.

Additionally, the second electrode lead <NUM> may be interposed between the upper pouch <NUM> and the lower pouch <NUM> such that parts of the second electrode lead <NUM> may be disposed in the internal space of the packaging material <NUM>. Additionally, the other parts of the second electrode lead <NUM> may be exposed outside of the packaging material <NUM>. For example, as shown in the configuration of <FIG>, the second electrode lead <NUM> may extend in the outward direction of the packaging material <NUM>, with the parts of the second electrode lead <NUM> exposed outside of the packaging material <NUM>.

When the first electrode tab <NUM> is a positive electrode tab and the second electrode tab <NUM> is a negative electrode tab, the first electrode lead <NUM> may be referred to as a positive electrode lead and the second electrode lead <NUM> may be referred to as a negative electrode lead.

Alternatively, when the first electrode tab <NUM> is a negative electrode tab and the second electrode tab <NUM> is a positive electrode tab, the first electrode lead <NUM> may be referred to as a negative electrode lead and the second electrode lead <NUM> may be referred to as a positive electrode lead.

One end of the first measuring lead <NUM> electrically contacts with the first measuring tab <NUM>. The other end of the first measuring lead <NUM> is exposed outside of the packaging material <NUM>. Additionally, parts of the first measuring lead <NUM> are inserted into the packaging material <NUM>. More specifically, the first measuring tab <NUM> extending out of the first measuring electrode plate <NUM> may be connected to the first measuring lead <NUM>. The connection between the first measuring tab <NUM> and the first measuring lead <NUM> may be carried out by a welding process. For example, as shown in the configuration of <FIG>, the first measuring lead <NUM> may be directly connected to the first measuring tab <NUM> extending out of the first measuring electrode plate <NUM>.

Additionally, the first measuring lead <NUM> may have the central part interposed between the upper pouch <NUM> and the lower pouch <NUM>, and parts of the first measuring lead <NUM> may be disposed in the internal space of the packaging material <NUM>. Additionally, the other parts of the first measuring lead <NUM> may be exposed outside of the packaging material <NUM>. For example, as shown in the configuration of <FIG>, the first measuring lead <NUM> may extend in the outward direction of the packaging material <NUM>, with the parts of the first measuring lead <NUM> exposed outside of the packaging material <NUM>.

One end of the second measuring lead <NUM> electrically contacts with the second measuring tab <NUM>. The other end of the second measuring lead <NUM> is exposed outside of the packaging material <NUM>. Additionally, parts of the second measuring lead <NUM> are inserted into the packaging material <NUM>. More specifically, the second measuring tab <NUM> extending out of the second measuring electrode plate <NUM> may be connected to the second measuring lead <NUM>. In this instance, the connection between the second measuring tab <NUM> and the second measuring lead <NUM> may be carried out by a welding process. For example, as shown in the configuration of <FIG>, the second measuring lead <NUM> may be directly connected to the second measuring tab <NUM> extending out of the second measuring electrode plate <NUM>.

Additionally, the second measuring lead <NUM> may have the central part interposed between the upper pouch <NUM> and the lower pouch <NUM>, and parts of the second measuring lead <NUM> may be disposed in the internal space of the packaging material <NUM>. Additionally, the other parts of the second measuring lead <NUM> may be exposed outside of the packaging material <NUM>. For example, as shown in the configuration of <FIG>, the second measuring lead <NUM> may extend in the outward direction of the packaging material <NUM>, with the parts of the second measuring lead <NUM> exposed outside of the packaging material <NUM>.

According to the present disclosure, it is possible to estimate the state of the secondary battery using the first measuring lead <NUM> and the second measuring lead <NUM>. Particularly, the SOH (state of health) of the secondary battery may be estimated based on a potential difference between the first measuring lead and the second measuring lead.

The first measuring tab <NUM> and the first measuring lead <NUM> may be integrated into one plate. The second measuring tab <NUM> and the second measuring lead <NUM> may be integrated into one plate.

Additionally, the first electrode lead <NUM>, the second electrode lead <NUM>, the first measuring lead <NUM> and the second measuring lead <NUM> may extend out of the packaging material <NUM> in the same direction. For example, as shown in the configuration of <FIG> and <FIG>, the first electrode lead <NUM>, the second electrode lead <NUM>, the first measuring lead <NUM> and the second measuring lead <NUM> may extend in +y-axis direction of <FIG> and <FIG>.

Accordingly, it is possible to easily measure the voltage (i.e. the potential difference) using the first measuring lead and the second measuring lead. The reason is that the first measuring lead and the second measuring lead may easily contact a measuring terminal as described below.

In the electrode assembly <NUM>, the positions of the first measuring tab <NUM> and the second measuring tab <NUM> may be different in the horizontal direction from the positions of the first electrode tab <NUM> and the second electrode tab <NUM>. For example, as shown in the configuration of <FIG> and <FIG>, the first measuring tab <NUM> and the second measuring tab <NUM> may be formed at different positions in the x-axis direction from the first electrode tab <NUM> and the second electrode tab <NUM>. Particularly, the first measuring tab <NUM> and the second measuring tab <NUM> may be provided between the first electrode tab <NUM> and the second electrode tab <NUM>.

Accordingly, the state of the secondary battery <NUM> may be easily estimated by the first measuring tab and the second measuring tab formed at different positions in the horizontal direction from the first electrode tab <NUM> and the second electrode tab <NUM> used to charge and discharge the secondary battery <NUM>.

<FIG> is a schematic exploded perspective view showing the configuration of the electrode assembly according to an embodiment of the present disclosure. However, for convenience of description, the separator is not shown in <FIG>. Additionally, in this embodiment, for the parts to which the description of the previous embodiment may be similarly applied, a detailed description is omitted herein, and it will be described primarily based on difference(s).

Referring to <FIG>, the electrode assembly <NUM> may be configured such that a plurality of electrode plates <NUM>, <NUM>, <NUM>, <NUM> is stacked in up-down direction. Particularly, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided at the position of the first electrode plate <NUM> or the second electrode plate <NUM> in place of at least one electrode plate of the plurality of first electrode plates <NUM> and the plurality of second electrode plates <NUM>. More specifically, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be stacked in the same layer among the plurality of electrode plates.

For example, as shown in the configuration of <FIG>, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided at the position of the first electrode plate <NUM> in place of the first electrode plate <NUM>. That is, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided in the same layer between two second electrode plates <NUM>. Additionally, although not shown in the drawing, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided at the position of the second electrode plate <NUM> in place of the second electrode plate <NUM>. That is, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided in the same layer between two first electrode plates <NUM>. According to this configuration of the present disclosure, it is possible to estimate the state of the secondary battery more accurately.

The electrode assembly <NUM> may further include an insulating element <NUM>. This will be described in more detail with reference to <FIG> and <FIG>.

<FIG> and <FIG> are schematic perspective views showing connection of the measuring electrode plates <NUM>, <NUM> and the insulating element <NUM> according to different embodiments of the present disclosure.

Referring to <FIG> and <FIG>, the insulating element <NUM> may fix the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM>. More specifically, the insulating element <NUM> may fix the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> such that the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be disposed in parallel in one layer among the plurality of electrode plates <NUM>, <NUM>.

For example, as shown in the configuration of <FIG>, the insulating element <NUM> may be made of an insulating material, and have the same size as the electrode plate provided in the electrode assembly <NUM>. Additionally, the insulating element <NUM> may have internal spaces <NUM> of the same size as the area of the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM>.

The internal space <NUM> formed in the insulating element <NUM> may be an empty space that is open in the vertical direction, with the open top and bottom in the same size as the area of the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> as shown in the configuration of <FIG>. Additionally, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be disposed in the internal space <NUM>. The first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be inserted and fixed into the internal space <NUM> of the insulating element <NUM> along the direction a of <FIG>. In this instance, the internal space into which the first measuring electrode plate <NUM> is inserted and the internal space into which the second measuring electrode plate <NUM> is inserted may be spaced a predetermined distance apart in the horizontal direction. Accordingly, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be kept in electrically insulated state when fixed in the insulating element <NUM>.

Alternatively, as shown in the configuration of <FIG>, the insulating element <NUM> may be made of an insulating material and disposed between the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM>. For example, the insulating element <NUM> may be formed in the shape of an elongated bar that extends in one direction (the left-right direction in the drawing). Additionally, the insulating element <NUM> may be interposed between the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> arranged in parallel in the horizontal direction, with the wide surfaces facing up and down, to separate the first measuring electrode plate <NUM> from the second measuring electrode plate <NUM>. Particularly, through this configuration, the insulating element <NUM> may electrically insulate the first measuring electrode plate <NUM> from the second measuring electrode plate <NUM>. According to this configuration of the present disclosure, insulation between the two measuring electrode plates <NUM>, <NUM> may be maintained.

The insulating element <NUM> may be configured such that the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be inserted into the insulating element <NUM>. More specifically, the insulating element <NUM> may have an inner grooves <NUM>. The inner groove <NUM> may extend in the lengthwise direction of the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> such that the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> are coupled to the inner grooves <NUM>. Here, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be inserted and fixed into the inner grooves <NUM> of the insulating element <NUM> in the direction a of <FIG>.

Additionally, the insulating element <NUM> may electrically insulate the first measuring electrode plate <NUM> from the second measuring electrode plate <NUM>. More specifically, the insulating element <NUM> may separate the first measuring electrode plate <NUM> from the second measuring electrode plate <NUM> to maintain a predetermined distance between the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM>. For example, as shown in the configuration of <FIG> and <FIG>, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be spaced apart by the insulating element <NUM> to prevent the contact between.

<FIG> is a schematic exploded perspective view showing the configuration of the electrode assembly according to another embodiment of the present disclosure. However, for convenience of description, the separator is not shown in <FIG>. Additionally, in this embodiment, for the parts to which the description of the previous embodiment may be similarly applied, a detailed description is omitted herein, and it will be described primarily based on difference(s).

Referring to <FIG>, the electrode assembly <NUM> may be configured such that a plurality of electrode plates is stacked in up-down direction. Particularly, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided at the position of two electrode plates in place of any two of the plurality of first electrode plates <NUM> or any two of the plurality of second electrode plates <NUM>. More specifically, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be stacked in different layers in place of each separate electrode plate of the plurality of electrode plates.

For example, as shown in the configuration of <FIG>, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided at the position of two first electrode plates <NUM> in place of the two first electrode plates <NUM>. That is, each of the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided between the second electrode plates <NUM>, and the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided in different layers.

Alternatively, although not shown in the drawing, the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided at the position of two second electrode plates <NUM> in place of the two second electrode plates <NUM>. That is, each of the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided between the first electrode plates <NUM>, and the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> may be provided in different layers. According to this configuration of the present disclosure, it is possible to easily manufacture the secondary battery <NUM>.

<FIG> is a schematic diagram showing the functional configuration of the apparatus <NUM> for estimating the state of the secondary battery <NUM> according to an embodiment of the present disclosure, and <FIG> is a schematic exploded perspective view showing the partial configuration of the secondary battery <NUM> and the apparatus <NUM> for estimating the state of the secondary battery <NUM> according to an embodiment of the present disclosure. Additionally, <FIG> and <FIG> are schematic diagrams showing the configuration of each of the plurality of inner terminals and the plurality of outer terminals of <FIG>.

The apparatus <NUM> is an apparatus that estimates the state of the secondary battery <NUM>, in particular, degradation of the secondary battery. Additionally, the apparatus <NUM> may estimate the life (i.e. SOH) of the secondary battery <NUM> through estimation of the state of the secondary battery <NUM>. Particularly, the apparatus <NUM> may be electrically connected to each of leads <NUM>, <NUM>, <NUM>, <NUM> of the secondary battery <NUM>.

The outer surfaces of the secondary battery <NUM> may be taped. For example, as shown in the configuration of <FIG>, the secondary battery <NUM> may be in the shape of a rectangular prism with the taped outer surfaces. Additionally, the secondary battery <NUM> may have a plurality of leads <NUM>, <NUM>, <NUM>, <NUM> disposed on one surface of the secondary battery <NUM>. For example, as shown in the configuration of <FIG>, the secondary battery <NUM> may include the first electrode lead <NUM>, the second electrode lead <NUM>, the first measuring lead <NUM> and the second measuring lead <NUM> on one surface in +y-axis direction of <FIG>.

The first electrode lead <NUM>, the second electrode lead <NUM>, the first measuring lead <NUM> and the second measuring lead <NUM> may be bent in upward or downward direction. Specifically, the first electrode lead <NUM>, the second electrode lead <NUM>, the first measuring lead <NUM> and the second measuring lead <NUM> may be bent in upward or downward direction with the flat surface facing in the outward direction of the secondary battery <NUM>. For example, as shown in the configuration of <FIG>, the first electrode lead <NUM>, the second electrode lead <NUM>, the first measuring lead <NUM> and the second measuring lead <NUM> may be bent in +z-axis direction or -z-axis direction, with the flat surface facing in +y-axis direction. Accordingly, the plurality of leads <NUM>, <NUM>, <NUM>, <NUM> may easily contact with the measuring terminals or the like.

Referring to <FIG>, the apparatus <NUM> for estimating the state of the secondary battery <NUM> according to the present disclosure includes a terminal case <NUM>, a voltage measuring unit <NUM> and a control unit <NUM>.

The terminal case <NUM> may be provided on one side of the secondary battery <NUM> and may be coupled to the secondary battery <NUM>. The terminal case <NUM> may be coupled to one side of the secondary battery <NUM> having the electrode leads <NUM>, <NUM>, <NUM>, <NUM>. For example, as shown in the configuration of <FIG>, the terminal case <NUM> may be located on one side of the secondary battery <NUM> in the direction b.

The terminal case <NUM> may have a coupling portion and may be coupled to one side of the secondary battery <NUM>. Although not shown, the terminal case <NUM> may have the coupling portion extending in the direction of the secondary battery <NUM> from the terminal case <NUM> on a surface of -y-axis direction of <FIG>, and the secondary battery <NUM> may have a predefined groove to which the coupling portion is fixed. Additionally, when the terminal case <NUM> approaches the secondary battery <NUM> in -y-axis direction of FI. G <NUM>, the coupling portion may be fixed into the groove.

The terminal case <NUM> includes the plurality of inner terminals and the plurality of outer terminals.

The plurality of inner terminals may be made of an electrically conductive material such as metal. Additionally, at least one of the plurality of inner terminals may be formed in the shape of a plate. Additionally, the plurality of inner terminals may be provided on a first surface (e.g., an inner surface) facing the electrode leads <NUM>, <NUM>, <NUM>, <NUM> of the secondary battery <NUM>. The first surface may be one surface configured to be coupled with the secondary battery <NUM> in the terminal case <NUM>. For example, as shown in the configuration of <FIG>, the plurality of inner terminals may be provided on one surface of the terminal case <NUM> facing the secondary battery <NUM> in -y-axis direction of <FIG>.

Additionally, the plurality of inner terminals is configured to contactable with each of the first electrode lead <NUM>, the second electrode lead <NUM>, the first measuring lead <NUM> and the second measuring lead <NUM>. More specifically, the plurality of inner terminals may be configured to selectively contact with each of the first electrode lead <NUM>, the second electrode lead <NUM>, the first measuring lead <NUM> and the second measuring lead <NUM>. The plurality of inner terminals may be configured to selectively contact with the electrode leads <NUM>, <NUM>, <NUM>, <NUM> of the secondary battery <NUM> separately in the case of charging/discharging the secondary battery <NUM> and the case of estimating the state of the secondary battery <NUM>.

The plurality of inner terminals include an inner charging/discharging terminals and an inner measuring terminals.

The inner charging/discharging terminals include a first inner positive electrode terminal <NUM> and a first inner negative electrode terminal <NUM>. The first inner positive electrode terminal <NUM> may be configured to electrically contact with all the first measuring lead <NUM>, the second measuring lead <NUM> and the first electrode lead <NUM>. Additionally, the first inner negative electrode terminal <NUM> may be configured to contact with the second electrode lead <NUM>.

For example, as shown in the configuration of <FIG> and <FIG>, the first inner positive electrode terminal <NUM> and the first inner negative electrode terminal <NUM> may be provided at the lower part in -z-axis direction on the inner surface of the terminal case <NUM> facing the secondary battery <NUM> in -y-axis direction of <FIG>. That is, the inner charging/discharging terminals may be provided at the lower part on one surface of the terminal case <NUM>.

When the first measuring lead <NUM> and the second measuring lead <NUM> are leads having positive polarity, the first inner positive electrode terminal <NUM> is also configured to electrically contact with the first measuring lead <NUM> and the second measuring lead <NUM>. Additionally, the first inner positive electrode terminal <NUM> may extend in the widthwise direction such that the first inner positive electrode terminal <NUM> may contact all the first measuring lead <NUM>, the second measuring lead <NUM> and the first electrode lead <NUM>. For example, as shown in the configuration of <FIG> and <FIG>, the first inner positive electrode terminal <NUM> may extend straight in the horizontal direction (x-axis direction).

The first inner negative electrode terminal <NUM> is configured to electrically contact with the second electrode lead <NUM> of the secondary battery <NUM>. To this end, when the terminal case <NUM> receives the secondary battery <NUM> or is coupled to the electrode lead of the secondary battery <NUM>, the first inner negative electrode terminal <NUM> may be disposed at the location facing the second electrode lead <NUM>. For example, as shown in the configuration of <FIG> and <FIG>, the first inner negative electrode terminal <NUM> may be provided on one side (right side) in +x-axis direction from the first inner positive electrode terminal <NUM>, facing the second electrode lead <NUM>. Although not shown in the drawing, when the first measuring lead <NUM> and the second measuring lead <NUM> are leads having the negative polarity, the first inner negative electrode terminal <NUM> may be also configured to electrically contact with the first measuring lead <NUM> and the second measuring lead <NUM>. In this case, the first inner negative electrode terminal <NUM> may extend straight in the widthwise direction (x-axis direction).

The inner measuring terminals may include a second inner positive electrode terminal <NUM>, a second inner negative electrode terminal <NUM>, a first inner measuring terminal <NUM> and a second inner measuring terminal <NUM>. The second inner positive electrode terminal <NUM> may be configured to contact with the first electrode lead <NUM>. Additionally, the second inner negative electrode terminal <NUM> may be configured to contact with the second electrode lead <NUM>. Additionally, the first inner measuring terminal <NUM> may be configured to contact with the first measuring lead <NUM>. Additionally, the second inner measuring terminal <NUM> may be configured to contact with the second measuring lead <NUM>.

For example, as shown in the configuration of <FIG> and <FIG>, the second inner positive electrode terminal <NUM>, the second inner negative electrode terminal <NUM>, the first inner measuring terminal <NUM> and the second inner measuring terminal <NUM> may be provided at the upper portion in +z-axis direction on one surface of the terminal case <NUM> facing the secondary battery <NUM> in -y-axis direction of <FIG>. That is, the inner measuring terminals may be provided at the upper portion on one surface of the terminal case <NUM>.

When the terminal case <NUM> receives the secondary battery <NUM> or is coupled to the electrode leads of the secondary battery <NUM>, the second inner positive electrode terminal <NUM> may be provided at the location facing the first electrode lead <NUM>. For example, as shown in the configuration of <FIG> and <FIG>, the second inner positive electrode terminal <NUM> may be provided facing the upper portion of the first electrode lead <NUM>.

The second inner negative electrode terminal <NUM> may be provided at the location facing the second electrode lead <NUM>. For example, as shown in the configuration of <FIG> and <FIG>, the second inner negative electrode terminal <NUM> may be provided facing the upper portion of the second electrode lead <NUM>.

When the terminal case <NUM> receives the secondary battery <NUM> or is coupled to the electrode leads of the secondary battery <NUM>, the first inner measuring terminal <NUM> may be provided at the location facing the first measuring lead <NUM>. For example, as shown in the configuration of <FIG> and <FIG>, the first inner measuring terminal <NUM> may be provided facing the upper portion of the first measuring lead <NUM>.

When the terminal case <NUM> receives the secondary battery <NUM> or is coupled to the electrode leads of the secondary battery <NUM>, the second inner measuring terminal <NUM> may be provided at the location facing the second measuring lead <NUM>. For example, as shown in the configuration of <FIG> and <FIG>, the second inner measuring terminal <NUM> may be provided facing the upper portion of the second measuring lead <NUM>.

The plurality of outer terminals may be made of an electrically conductive material such as metal. Additionally, the outer terminals may be in the shape of a plate. Additionally, the plurality of outer terminals may be provided on a second surface (e.g., outer surface) provided in the outward direction from the first surface facing the electrode lead of the secondary battery <NUM>. That is, the first surface and the second surface may face or be opposed to each other. Here, the second surface may be a surface of the terminal case <NUM> facing away from the secondary battery <NUM>. For example, as shown in the configuration of <FIG>, the plurality of outer terminals may be provided on one surface of the terminal case <NUM> facing away from the secondary battery <NUM> in +y-axis direction of <FIG>.

Additionally, the plurality of outer terminals may be electrically connectable to the plurality of inner terminals respectively. More specifically, the plurality of outer terminals may be configured to selectively contact with the plurality of inner terminals respectively. The plurality of outer terminals may be configured to contact with the plurality of inner terminals separately in each of the case of charging/discharging the secondary battery <NUM> and the case of estimating the SOH of the secondary battery <NUM>.

The plurality of outer terminals may include an outer charging/discharging terminals and an outer measuring terminals.

The outer charging/discharging terminals may include an outer positive electrode terminal <NUM> and an outer negative electrode terminal <NUM>. For example, as shown in the configuration of <FIG> and <FIG>, the outer positive electrode terminal <NUM> may be provided at the edge portion in -x-axis direction on one surface of the terminal case <NUM>. Here, the outer positive electrode terminal <NUM> may be provided at the location facing the first inner positive electrode terminal <NUM> and the second inner positive electrode terminal <NUM>. Additionally, the outer negative electrode terminal <NUM> may be provided at the edge portion in +x-axis direction on one surface of the terminal case <NUM>. Here, the outer negative electrode terminal <NUM> may be provided at the location facing the first inner negative electrode terminal <NUM> and the second inner negative electrode terminal <NUM>.

The outer positive electrode terminal <NUM> may be electrically connected to each of the first inner positive electrode terminal <NUM> and the second inner positive electrode terminal <NUM>. Additionally, the outer negative electrode terminal <NUM> may be electrically connected to each of the first inner negative electrode terminal <NUM> and the second inner negative electrode terminal <NUM>. Its detailed description will be provided in the description of <FIG>.

The outer measuring terminals may include a first outer measuring terminal <NUM> and a second outer measuring terminal <NUM>. For example, as shown in the configuration of <FIG> and <FIG>, the first outer measuring terminal <NUM> and the second outer measuring terminal <NUM> may be provided between the outer charging/discharging terminals <NUM>, <NUM>. That is, the first outer measuring terminal <NUM> and the second outer measuring terminal <NUM> may be provided between the outer positive electrode terminal <NUM> and the outer negative electrode terminal <NUM>. Here, the first outer measuring terminal <NUM> may be provided at the location facing the first inner measuring terminal <NUM>. Additionally, the second outer measuring terminal <NUM> may be provided at the location facing the second inner measuring terminal <NUM>.

The first outer measuring terminal <NUM> may be electrically connected to the first inner measuring terminal <NUM>. Additionally, the second outer measuring terminal <NUM> may be electrically connected to the second inner measuring terminal <NUM>. Its detailed description will be provided in the description of <FIG>.

The voltage measuring unit <NUM> may be electrically connected to at least two of the plurality of outer terminals to measure the voltage between the two terminals <NUM>, <NUM>. Additionally, the voltage measuring unit <NUM> may be electrically connected to at least one of the plurality of outer terminals. Additionally, the voltage measuring unit <NUM> may be electrically connected to the first measuring lead <NUM> and the second measuring lead <NUM> through the plurality of outer terminals to measure the voltage of each of the first measuring lead <NUM> and the second measuring lead <NUM>.

The control unit <NUM> may be configured to estimate the SOH of the secondary battery based on the potential difference between the first measuring lead <NUM> and the second measuring lead <NUM> measured by the voltage measuring unit <NUM>. Additionally, the control unit <NUM> may receive the voltage value of each of the first measuring lead <NUM> and the second measuring lead <NUM> from the voltage measuring unit <NUM>. Through this, the control unit <NUM> may calculate the potential difference between the voltage values of the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM>. Additionally, the control unit <NUM> may estimate the SOH of the secondary battery using the calculated potential difference.

Meanwhile, to perform the above-described operation, the control unit <NUM> may selectively include a processor, an Application-Specific Integrated Circuit (ASIC), a chipset, a logic circuit, register, a communication modem and/or a data processing device, known in the art.

The apparatus <NUM> for estimating the state of the secondary battery <NUM> may further include a memory unit <NUM> as shown in the configuration of <FIG>.

The memory unit <NUM> may include a lookup table that defines the SOH of the secondary battery corresponding to the potential difference between the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM>. Additionally, the memory unit <NUM> may include necessary information for the control unit <NUM> to calculate the potential difference. Here, the control unit <NUM> may estimate the SOH of the secondary battery using the potential difference-SOH lookup table of the secondary battery <NUM>.

Additionally, the memory unit <NUM> is not limited to a particular type, and includes any type of storage medium that can record and erase information. For example, the memory unit <NUM> may be RAM, ROM, register, hard disk, an optical recording medium or a magnetic recording medium. Additionally, the memory unit <NUM> may be electrically connected to the control unit <NUM> through, for example, a data bus, to allow the control unit <NUM> to access. Additionally, the memory unit <NUM> may store and/or update and/or erase and/or transmit programs including various control logics executed by the control unit <NUM>, and/or data generated when the control logics are executed.

The apparatus <NUM> for estimating the state of the secondary battery <NUM> may further include a switching element <NUM>.

The switching element <NUM> may be provided between the secondary battery <NUM> and the terminal case <NUM>. That is, the switching element <NUM> may be provided between the plurality of electrode leads <NUM>, <NUM>, <NUM>, <NUM> and the plurality of inner terminals <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. Additionally, the switching element <NUM> may be configured to selectively change the electrical contact between the second electrode lead <NUM>, the first measuring lead <NUM>, the second measuring lead <NUM> and the first electrode lead <NUM>, and the plurality of inner terminals <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. For example, a switching bar <NUM> that may control the switching element <NUM> may be provided on one side of the terminal case <NUM>. Alternatively, the switching element <NUM> is configured to receive and transmit electrical signals from/to the control unit <NUM>, and may be controlled by the control signals, such as turn-on and/or turn-off, transmitted from the control unit <NUM>.

For example, when the switching bar <NUM> is provided in the terminal case <NUM>, as shown in the configuration of <FIG>, the switching bar <NUM> may be configured to switch a normal mode and a measurement mode. For example, when the switching bar <NUM> goes up in +z-axis direction, the measurement mode may be selected, and when the switching bar <NUM> goes down in -z-axis direction, the normal mode may be selected.

Meanwhile, when the switching element <NUM> is provided between the plurality of electrode leads and the plurality of inner terminals, the switching element <NUM> may be implemented as an electrical circuit including a plurality of switches. Its detailed description will be provided in the description of <FIG>.

<FIG> and <FIG> are schematic diagrams showing connection of the plurality of electrode leads <NUM>, <NUM>, <NUM>, <NUM> and the plurality of inner terminals <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> according to an embodiment of the present disclosure.

First, referring to <FIG>, the inner charging/discharging terminals <NUM>, <NUM> may be electrically connected to the plurality of electrode leads of the secondary battery <NUM>.

The first inner positive electrode terminal <NUM> may be electrically connected to all the first measuring lead <NUM>, the second measuring lead <NUM> and the first electrode lead <NUM>. In this case, the first measuring lead <NUM> and the second measuring lead <NUM> have the positive polarity. For example, as shown in the configuration of <FIG>, the first inner positive electrode terminal <NUM> may be connected to each of the first measuring lead <NUM>, the second measuring lead <NUM> and the first electrode lead <NUM>. Through this configuration, when the secondary battery <NUM> is charged/discharged, the first inner positive electrode terminal <NUM> may be electrically connected to all the first electrode plates <NUM> provided in the secondary battery <NUM>.

The first inner negative electrode terminal <NUM> may be electrically connected to the second electrode lead <NUM>. For example, as shown in the configuration of <FIG>, the first inner negative electrode terminal <NUM> may be connected to the second electrode lead <NUM> one-to-one. Through this configuration, when the secondary battery <NUM> is charged/discharged, the first inner negative electrode terminal <NUM> may be electrically connected to all the second electrode plates <NUM> provided in the secondary battery <NUM>.

Referring to <FIG>, the inner measuring terminal according to an embodiment of the present disclosure may be electrically connected to the plurality of electrode leads <NUM>, <NUM>, <NUM>, <NUM> of the secondary battery <NUM>.

The second inner positive electrode terminal <NUM> may be electrically connected to the first electrode lead <NUM>. More specifically, the second inner positive electrode terminal <NUM> may be connected to the first electrode lead <NUM> one-to-one.

The second inner negative electrode terminal <NUM> may be electrically connected to the second electrode lead <NUM>. More specifically, the second inner negative electrode terminal <NUM> may be connected to the second electrode lead <NUM> one-to-one.

The first inner measuring terminal <NUM> may be electrically connected to the first measuring lead <NUM>. More specifically, the first inner measuring terminal <NUM> may be connected to the first measuring lead <NUM> one-to-one.

The second inner measuring terminal <NUM> may be electrically connected to the second measuring lead <NUM>. More specifically, the second inner measuring terminal <NUM> may be connected to the second measuring lead <NUM> one-to-one.

Through this configuration, the first inner measuring terminal <NUM> and the second inner measuring terminal <NUM> may be electrically connected to the first measuring electrode plate <NUM> and the second measuring electrode plate <NUM> provided in the electrode assembly <NUM> through the first measuring lead <NUM> and the second measuring lead <NUM> respectively.

<FIG> is a schematic diagram showing connection between the plurality of inner terminals <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and the plurality of outer terminals <NUM>, <NUM>, <NUM>, <NUM> provided in the terminal case <NUM> according to an embodiment of the present disclosure.

Referring to <FIG>, the plurality of inner terminals <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and the plurality of outer terminals <NUM>, <NUM>, <NUM>, <NUM> may be electrically connected to each other.

The outer positive electrode terminal <NUM> may be electrically connected to each of the first inner positive electrode terminal <NUM> and the second inner positive electrode terminal <NUM>. More specifically, when the terminal case <NUM> runs in the normal mode, the outer positive electrode terminal <NUM> may transmit and receive the charging/discharging current through the electrical circuit connected to the first inner positive electrode terminal <NUM>. Additionally, when the terminal case <NUM> runs in the measurement mode, the outer positive electrode terminal <NUM> may transmit and receive the charging/discharging current through the electrical circuit connected to the second inner positive electrode terminal <NUM>.

The outer negative electrode terminal <NUM> may be electrically connected to each of the first inner negative electrode terminal <NUM> and the second inner negative electrode terminal <NUM>. More specifically, when the terminal case <NUM> runs in the normal mode, the outer negative electrode terminal <NUM> may transmit and receive the charging/discharging current through the electrical circuit connected to the first inner negative electrode terminal <NUM>. Additionally, when the terminal case <NUM> runs in the measurement mode, the outer negative electrode terminal <NUM> may transmit and receive the charging/discharging current through the electrical circuit connected to the second inner negative electrode terminal <NUM>.

The first outer measuring terminal <NUM> may be electrically connected to the first inner measuring terminal <NUM>. More specifically, when the terminal case <NUM> runs in the measurement mode, the first outer measuring terminal <NUM> may be electrically connected to the first measuring electrode plate <NUM> through the electrical circuit connected to the first inner measuring terminal <NUM>.

The second outer measuring terminal <NUM> may be electrically connected to the second inner measuring terminal <NUM>. More specifically, when the terminal case <NUM> runs in the measurement mode, the second outer measuring terminal <NUM> may be electrically connected to the second measuring electrode plate <NUM> through the electrical circuit connected to the second inner measuring terminal <NUM>.

<FIG> is a schematic diagram showing parts of the apparatus for estimating the state of the secondary battery <NUM> according to an embodiment of the present disclosure.

Referring to <FIG>, the voltage measuring unit <NUM> may be electrically connected to the first outer measuring terminal <NUM> and the second outer measuring terminal <NUM>. Here, the first outer measuring terminal <NUM> is electrically connected to the first measuring electrode plate <NUM> through the first inner measuring terminal <NUM> and the first measuring lead <NUM>. Additionally, the second outer measuring terminal <NUM> is electrically connected to the second measuring electrode plate <NUM> through the second inner measuring terminal <NUM> and the second measuring lead <NUM>.

The voltage measuring unit <NUM> may measure the voltage of the first measuring electrode plate <NUM> by measuring the voltage applied to the first outer measuring terminal <NUM>. Additionally, the voltage measuring unit <NUM> may measure the voltage of the second measuring electrode plate <NUM> by measuring the voltage applied to the second outer measuring terminal <NUM>.

The voltage measuring unit <NUM> may measure the voltage applied to the first outer measuring terminal <NUM> and the voltage applied to the second outer measuring terminal <NUM> and transmit the measured voltage values to the control unit <NUM>. Additionally, the control unit <NUM> may calculate a difference (i.e., a potential difference) between the two received voltage values, and estimate the SOH of the secondary battery <NUM> using the calculated potential difference. In this case, the control unit <NUM> may refer to the potential difference-SOH lookup table stored in the memory unit <NUM>. For example, when a potential difference between the voltage value of the first measuring electrode plate <NUM> and the voltage value of the second measuring electrode plate <NUM> is <NUM> mV or more, the control unit <NUM> may estimate that the secondary battery is degraded.

<FIG> is a schematic diagram showing the switching element connected between the plurality of electrode leads <NUM>, <NUM>, <NUM>, <NUM> and the plurality of inner terminals <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> according to an embodiment of the present disclosure.

Referring to <FIG>, the switching element <NUM> may be provided between the plurality of electrode leads <NUM>, <NUM>, <NUM>, <NUM> and the plurality of inner terminals <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. More specifically, the switching element <NUM> may be configured to selectively change the electrical connection between the plurality of electrode leads <NUM>, <NUM>, <NUM>, <NUM> and the plurality of inner terminals <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>.

The switching element <NUM> may include a normal mode circuit <NUM> and a measurement mode circuit <NUM>. The normal mode circuit <NUM> may include a plurality of unit switches <NUM> for normal mode. The measurement mode circuit <NUM> may include a plurality of unit switches <NUM> for measurement mode.

For example, as shown in the configuration of <FIG>, the normal mode circuit <NUM> may electrically connect each of the plurality of electrode leads <NUM>, <NUM>, <NUM>, <NUM> to the inner charging/discharging terminals <NUM>, <NUM>. More specifically, the unit switch <NUM> may be provided between the first electrode lead <NUM> and the first inner positive electrode terminal <NUM>, to open/close the electrical circuit between the first electrode lead <NUM> and the first inner positive electrode terminal <NUM>. Additionally, the unit switch <NUM> may be provided between the second electrode lead <NUM> and the first inner negative electrode terminal <NUM>, to open/close the electrical circuit between the second electrode lead <NUM> and the first inner negative electrode terminal <NUM>. Additionally, the unit switch <NUM> may be provided between the first measuring lead <NUM> and the first inner positive electrode terminal <NUM>, to open/close the electrical circuit between the first measuring lead <NUM> and the first inner positive electrode terminal <NUM>. Additionally, the unit switch <NUM> may be provided between the second measuring lead <NUM> and the first inner positive electrode terminal <NUM>, to open/close the electrical circuit between the second measuring lead <NUM> and the first inner positive electrode terminal <NUM>.

Additionally, the measurement mode circuit <NUM> may electrically connect each of the plurality of electrode leads <NUM>, <NUM>, <NUM>, <NUM> to the inner measuring terminals <NUM>, <NUM>, <NUM>, <NUM>. More specifically, the unit switch <NUM> may be provided between the first electrode lead <NUM> and the second inner positive electrode terminal <NUM>, to open/close the electrical circuit between the first electrode lead <NUM> and the second inner positive electrode terminal <NUM>. Additionally, the unit switch <NUM> may be provided between the second electrode lead <NUM> and the second inner negative electrode terminal <NUM>, to open/close the electrical circuit between the second electrode lead <NUM> and the second inner negative electrode terminal <NUM>. Additionally, the unit switch <NUM> may be provided between the first measuring lead <NUM> and the first inner measuring terminal <NUM>, to open/close the electrical circuit between the first measuring lead <NUM> and the first inner measuring terminal <NUM>. Additionally, the unit switch <NUM> may be provided between the second measuring lead <NUM> and the second inner measuring terminal <NUM>, to open/close the electrical circuit between the second measuring lead <NUM> and the second inner measuring terminal <NUM>.

The control unit <NUM> may be connected to the normal mode circuit <NUM> and the measurement mode circuit <NUM> to transmit and receive electrical signals to/from them, to control the turn-on and/or turn-off operation of each unit switch <NUM> and each unit switch <NUM>.

For example, when the terminal case <NUM> runs in the normal mode, the control unit <NUM> may turn on the normal mode circuit <NUM> and turn off the measurement mode circuit <NUM>. Or, when the terminal case <NUM> runs in the measurement mode, the control unit <NUM> may turn off the normal mode circuit <NUM>, and turn on the measurement mode circuit <NUM>.

Additionally, when the control logics are implemented in software, the control unit may be implemented as a set of program modules. In this instance, the program module may be stored in the memory device and executed by the processor.

Additionally, at least one of the various control logics of the control unit may be combined, and the combined control logics are not limited to a particular type and include any type that can be written in computer-readable coding systems and read and accessed by the computer. For example, the recording media may include at least one selected from the group consisting of ROM, RAM, register, CD-ROM, magnetic tape, hard disk, floppy disk and an optical data recording device. Additionally, the coding systems may be stored and executed in computers connected via a network in distributed manner. Additionally, functional programs, codes and segments for implementing the combined control logics may be easily inferred by programs in the technical field pertaining to the present disclosure.

Claim 1:
An apparatus (<NUM>) for estimating a state of a secondary battery (<NUM>), connectable to a positive electrode lead (<NUM>), a negative electrode lead (<NUM>), a first measuring lead (<NUM>) and a second measuring lead (<NUM>) included in the secondary battery (<NUM>), the apparatus (<NUM>) comprising:
a terminal case (<NUM>) including a plurality of inner terminals, each configured to be contactable with the positive electrode lead (<NUM>), the negative electrode lead (<NUM>), the first measuring lead (<NUM>), or the second measuring lead (<NUM>) on a first surface of the terminal case (<NUM>), and a plurality of outer terminals configured to be respectively electrically connectable to the plurality of inner terminals on a second surface facing the first surface of the terminal case (<NUM>);
a voltage measuring unit (<NUM>) configured to be electrically connected to at least two of the plurality of outer terminals, and measure a potential difference between the first measuring lead (<NUM>) and the second measuring lead (<NUM>); and
a control unit (<NUM>) configured to estimate a state of health of the secondary battery (<NUM>) based on the potential difference between the first measuring lead (<NUM>) and the second measuring lead (<NUM>) measured by the voltage measuring unit (<NUM>),
characterized in that the plurality of inner terminals includes inner charging/discharging terminals (<NUM>, <NUM>), and
the inner charging/discharging terminals (<NUM>, <NUM>) include:
a first inner positive electrode terminal (<NUM>) configured to be connectable to each of the first measuring lead (<NUM>), the second measuring lead (<NUM>) and the positive electrode lead (<NUM>); and
a first inner negative electrode terminal (<NUM>) configured to be connectable to the negative electrode lead (<NUM>).