EMERGENCY CALL SYSTEM AND METHOD FOR CONTROLLING OPERATION OF THE SAME

Abstract

An emergency call (E-call) system may execute control such that an E-call battery operates in a 1 series 1 parallel (1S1P) mode or a 1 series 2 parallel (1S2P) mode depending on the temperature of a usage environment of the E-call battery to improve the discharge performance of the E-call battery in a low-temperature environment. A method for controlling an operation of the E-call system is also disclosed.

Claims

1. An emergency call (E-call) system, comprising: an E-call battery including first and second battery banks; a parallel connection switch configured to control an electrical parallel connection between the first and second battery banks of the E-call battery; a temperature data acquisition controller configured to acquire battery usage environment temperature data, at regular intervals, from an external system connected to the E-call battery; and a switch controller configured to control on/off of the parallel connection switch based on a battery usage environment temperature value acquired by the temperature data acquisition controller.

2. The E-call system of claim 1, wherein the parallel connection switch is configured to be initially in an off state.

3. The E-call system of claim 1, further comprising a comparison controller configured to compare the battery usage environment temperature value acquired by the temperature data acquisition controller with a predetermined reference temperature, wherein the comparison controller is configured to: output a low-temperature signal when the acquired battery usage environment temperature value is less than the predetermined reference temperature; and output a normal-temperature signal when the acquired battery usage environment temperature value is equal to or higher than the predetermined reference temperature.

4. The E-call system of claim 3, wherein the switch controller is configured to output a turn-on signal to the parallel connection switch when the low-temperature signal is output from the comparison controller; and output a turn-off signal to the parallel connection switch when the normal-temperature signal is output from the comparison controller, wherein the low-temperature signal is for a low temperature, the normal-temperature signal is of a normal temperature, and the low temperature is lower than the normal temperature.

5. The E-call system of claim 3, wherein the predetermined reference temperature is 0 degrees Celsius.

6. The E-call system of claim 1, wherein the E-call battery comprises: a first output path configured to connect an output of the first battery bank to an output terminal of the E-call battery; a second output path configured to connect an output of the second battery bank to the output terminal of the E-call battery; and a parallel connection path configured to connect the first output path and the second output path in parallel to form the electrical parallel connection between the first battery bank and the second battery bank, wherein: the parallel connection switch is disposed on the parallel connection path to open or close the parallel connection path; and the E-call battery is configured to be driven in a 1 series 2 parallel (1S2P) mode in which the first battery bank and the second battery bank are connected in parallel, when the parallel connection switch is turned on by the switch controller, and is configured to be driven in a 1 series 1 parallel (1S1P) mode in which a parallel connection of the first battery bank and the second battery bank is released and only an output of one of the first battery bank and the second battery bank is connected to the output terminal of the E-call battery, when the parallel connection switch is turned off by the switch controller.

7. The E-call system of claim 6, wherein a resistor having a predetermined resistance component is disposed on the second output path.

8. The E-call system of claim 6, wherein a first discharge control switch and a second discharge control switch for opening and closing the first output path and the second output path are disposed on the first output path and the second output path, respectively.

9. The E-call system of claim 8, wherein the switch controller is configured to: control on/off of the parallel connection switch; control both the first discharge control switch and the second discharge control switch to be on when the parallel connection switch is controlled to be on; and control only one of the first discharge control switch and the second discharge control switch to be on when the parallel connection switch is controlled to be off

10. The E-call system of claim 9, wherein the switch controller is configured to: control the first discharge control switch to be on when a period of use of the first battery bank is equal to or shorter than a predetermined reference period of use; and control the second discharge control switch to be on when the period of use of the first battery bank is longer than the predetermined reference period of use.

11. A method for controlling an operation of an emergency call (E-call) battery including first and second battery banks arranged in parallel, the method comprising: acquiring temperature data by acquiring battery usage environment temperature data, at regular intervals, from an external system connected to the E-call battery; comparing a battery usage environment temperature value acquired in the acquiring of the temperature data with a predetermined reference temperature to determine whether the battery usage environment temperature value is less than or equal to or higher than the predetermined reference temperature; controlling a parallel connection switch to be on/off according to a comparison result in the comparing with the predetermined reference temperature, the parallel connection switch being configured to control an electrical parallel connection between the first and second battery banks; and discharging the E-call battery with an electric connection structure corresponding to a control of the parallel connection switch in the controlling of the parallel connection switch.

12. The method of claim 11, wherein the controlling of the parallel connection switch comprises: turning on the parallel connection switch when the acquired battery usage environment temperature value is less than the predetermined reference temperature based on the comparison result; and turning off the parallel connection switch when the acquired battery usage environment temperature value is equal to or higher than the predetermined reference temperature based on the comparison result.

13. The method of claim 12, wherein the discharging of the E-call battery comprises: performing a 1 series 2 parallel (1S2P) mode driving control under which the E-call battery is discharged in the 1S2P mode in which the first and second battery banks are connected in parallel when the parallel connection switch is turned on in the controlling of the parallel connection switch; and performing a 1 series 1 parallel (1S1P) mode driving control under which the E-call battery is discharged in the 1S1P mode in which a parallel connection of the first battery bank and the second battery bank is released when the parallel connection switch is turned off in the controlling of the parallel connection switch.

14. The method of claim 13, wherein the performing of the 1S1P mode driving control comprises performing output of a main use bank by selecting the main use bank out of the first and second battery banks and controlling a discharge control switch of the main use bank to be on.

15. The method of claim 14, wherein the performing of the output of the main use bank comprises: determining a bank use state by calculating at least one of an accumulated use time or a state of charge (SOC) or state of health (SOH) of the first battery bank or the second battery bank; and selecting the main use bank according to the at least one of the accumulated use time or the SOC or SOH of the first battery bank or the second battery bank which is calculated in the determining of the bank use state.

16. The method of claim 11, wherein the predetermined reference temperature is 0 degrees Celsius.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG. 1 is a diagram of the relate art;

[0027] Each of FIGS. 2(a) and 2(b) is a diagram schematically illustrating a battery system for E-call in accordance with an exemplary embodiment; and

[0028] FIG. 3 is a flowchart illustrating a method for controlling an operation of the E-call battery in accordance with an exemplary embodiment.

[0029] FIG. 4 is a flowchart illustrating a method for controlling an operation of the E-call battery in accordance with another exemplary embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

[0030] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily perform the present disclosure. However, the present disclosure may be implemented by various modifications and is not limited to the exemplary embodiments described herein. In the drawings, in order to clarify the present disclosure, parts that are not related to description are omitted and like reference numerals represent like elements throughout the specification.

[0031] Hereinafter, exemplary embodiments will be described in detail with reference to the drawings.

[0032] FIG. 1 is a diagram schematically illustrating the related art.

[0033] In the configuration of the related art, an additional battery cell is connected in series to increase the output voltage when a voltage drop occurs due to a low temperature. In the related art, it is possible to solve the driving problem at a low temperature; however, a problem of matching the voltage drop due to the low temperature to the additional voltage due to the additional battery cell, a problem that the output voltage becomes higher than necessary when the additional battery cell is connected, or the like, occurs. According to the exemplary embodiments, which will be described later, it is possible to solve the aforementioned problems and effectively cope with a voltage drop problem due to a low temperature.

[0034] 1. E-call System in Accordance with Exemplary Embodiments

[0035] Each of FIGS. 2(a) and 2(b) is a diagram schematically illustrating an emergency call (E-call) system in accordance with an exemplary embodiment.

[0036] Referring to FIGS. 2(a) and 2(b), the E-call systems of exemplary embodiments may include the following configurations.

[0037] 1.1 E-call Battery 100

[0038] A battery 100 for E-call (E-call battery 100) of an exemplary embodiment has a structure in which two battery banks 100a and 100b are arranged in parallel.

[0039] In this case, the first and second battery banks 100a and 100b constituting the E-call battery 100 have a structure arranged in parallel, and mutual electrical parallel connection therebetween is limited according to the on/off operation of a parallel connection switch 200 to be described later.

[0040] The E-call battery 100 may be initially driven in a 1 Series 1 Parallel (1S1P) mode in which the first and second battery banks 100a and 100b are not electrically connected in parallel, and thereafter, may be driven in the 1S1P mode or a 1 Series 2 Parallel (1S2P) mode according to the on/off of the parallel connection switch 200 to be described later.

1 Series 1 Parallel (1S1P) Mode

[0041] The 1S1P mode is a mode in which the parallel connection switch 200 is turned off to open a parallel connection path of the two battery banks 100a and 100b, and the voltage of one battery bank is output. As shown in FIG. 2(a), the output of the second battery bank 100b is connected to an output terminal through a resistor R.

1 Series 2 Parallel (1S2P) Mode

[0042] The 1S2P mode is a mode in which the parallel connection switch 200 is turned on and the two battery banks 100a and 100b are connected in parallel to output a parallel voltage.

[0043] 1.2. Parallel Connection Switch 200

[0044] The parallel connection switch 200 is configured to control the connecting or opening of an electrical parallel connection path between the first and second battery banks 100a and 100b constituting the E-call battery 100. The parallel connection switch 200 may be controlled to be on or off by the control of a switch controller 500 to be described later such that the E-call battery 100 is driven in the 1S2P mode or is driven in the 1S1P mode.

[0045] That is, the parallel connection switch 200 is to function as an auxiliary device for preventing a phenomenon that the voltage suddenly drops in the E-call battery 100 due to the very low temperature. Although a filed-effect transistor (FET) is shown as an example of the parallel connection switch 200 in the drawing, this is only an example among various switching devices that may be employed in the exemplary embodiment, and is not limited to the FET.

[0046] 1.3. Temperature data acquisition controller 300

[0047] A temperature data acquisition controller 300 is configured to acquire battery usage environment temperature data from an external system (not shown) connected to the E-call battery 100 at regular intervals.

[0048] Here, the external system may be a communication device of an electric vehicle or a small mobile device, or a single mobile communication device.

[0049] 1.4. Comparison controller 400

[0050] A comparison controller 400 is configured to perform comparison to check whether a battery usage environment temperature value T acquired by the temperature data acquisition controller 300 is equal to or higher than or less than a predetermined reference temperature.

[0051] Here, the predetermined reference temperature value may be 0 degrees Celsius.

[0052] In other words, the comparison controller 400 performs the comparison to check whether the battery usage environment temperature is less than or equal to or higher than 0 degrees Celsius.

[0053] For example, as a result of the comparison, when the battery usage environment temperature is less than the reference temperature of 0 degrees Celsius, a low-temperature signal indicating the fact may be output. On the other hand, as the result of the comparison, when the battery usage environment temperature is equal to or higher than the reference temperature of 0 degrees Celsius, a normal-temperature signal indicating the fact may be output.

[0054] 1.5. Switch Controller 500

[0055] The switch controller 500 is configured to control on/off of the parallel connection switch 200 according to the comparison result of the comparison controller 400.

[0056] Specifically, as the result of the comparison, when the battery usage environment temperature is less than the reference temperature of 0 degrees Celsius, the parallel connection switch 200 may be turned on. For example, when the low-temperature signal is output from the comparison controller 400, the switch controller 500 may output a turn-on signal to the parallel connection switch 200 to connect the parallel connection path between the first and second battery banks 100a and 100b and drive the E-call battery 100 in the 1S2P mode. Here, when the turn-on signal is output, the parallel connection switch 200 may implement its turn-on by receiving a voltage of approximately 3.3 V applied from an external control power supply (not shown), for example, a 12V auxiliary battery (not shown).

[0057] Meanwhile, as the result of the comparison, when the battery usage environment temperature is higher than the reference temperature of 0 degrees Celsius, the parallel connection switch 200 may be turned off. For example, when the normal-temperature signal is output from the comparison controller 400, the switch controller 500 may output a turn-off signal to the parallel connection switch 200 to open the parallel connection path between the first and second battery banks 100a and 100b and drive the E-call battery 100 in the 1S1P mode. Here, when the turn-off signal is output, the parallel connection switch 200 may implement its turn-off by receiving a voltage of 0 V applied.

[0058] On the other hand, in another exemplary embodiment shown in FIG. 2(b) described below, the switch controller 500 controls on/off of a first discharge control switch 110a and a second discharge control switch 110b, as well as the parallel connection switch 200. On/off control algorithm of each switch will be described later.

[0059] The temperature data acquisition controller 300, the comparison controller 400, and the switch controller 500 may be included as one configuration of a battery management system.

[0060] As described above, by applying a switch between the battery banks constituting the E-call battery, and when the battery usage environment temperature is very low, discharging the battery in the 1S2P mode by controlling the switch to electrically connect the battery banks to each other in parallel, it is possible to suppress a sudden voltage drop due to an increase in internal resistance of the battery.

Another Exemplary Embodiment

[0061] 1.6. First Discharge Control switch 110a and Second Discharge Control Switch 110b

[0062] In another exemplary embodiment, as shown in FIG. 2(b), a battery pack is provided in which a first discharge control switch 110a and a second discharge control switch 110b are disposed between the first and second battery banks 100a and 100b and the output terminal instead of the resistor R.

[0063] In the present exemplary embodiment, as the switch controller 500 controls the parallel connection switch 200 and the first and second discharge control switches, one of the first and second battery banks 100a and 100b is selectively connected to the output terminal. That is, in the present exemplary embodiment, one of the first and second battery banks may be selectively used for external output depending on the remaining amounts of the first and second batteries, and the other one may be used for coping with a low-temperature voltage drop. In this case, it is desirable to set both the first and second battery banks 100a and 100b to satisfy an output voltage/current requirement of an output cell.

[0064] In one or more aspects, a controller (e.g., a temperature data acquisition controller 300, a comparison controller 400, or a switch controller 500) may include one or more processors (e.g., microprocessors or microcontrollers). In one or more examples, a processor may be configured to execute code or instructions to perform the operations and functionality described herein. In one or more examples, a processor may be configured to monitor and/or control the operation of the components in the E-call battery 100. In one or more examples, a processor may be a microprocessor, a microcontroller, a digital signal processor, an application specific integrated circuit, a field programmable gate array, a programmable logic device, a state machine, gated logic, discrete hardware components, or a combination of the foregoing. One or more sequences of instructions may be software or firmware stored on and read from a memory (e.g., a memory within a processor or a memory associated with a processor) or received from an external device (e.g., a computing device). A memory may represent examples of machine or computer readable media on which instructions/code executable by a processor may be stored. Machine or computer readable media may be any medium or media used to provide instructions to a processor, including, for example, non-transitory media, volatile media, buffers, and/or non-volatile media, such as electronic media, optical media, and/or magnetic media.

[0065] 2. Method for Controlling Operation of E-call Battery in Accordance with Exemplary Embodiment (1)

[0066] FIG. 3 is a flowchart illustrating a method for controlling an operation of the E-call battery in accordance with an exemplary embodiment.

[0067] Referring to FIG. 3, the method according to the present exemplary embodiment may include the following steps.

[0068] 2.1. Temperature Data Acquisition Step (S100)

[0069] A temperature data acquisition step S100 is a step of acquiring battery usage environment temperature data from an external system (not shown) connected to the E-call battery 100 having a 1S2P structure at regular intervals.

[0070] Here, the external system may be a vehicle.

[0071] 2.2. Reference Temperature Comparison Step (S200)

[0072] A reference temperature comparison step S200 is a step of comparing a battery usage environment temperature acquired in the temperature data acquisition step S100 with a predetermined reference temperature to check whether the battery usage environment temperature is less than or equal to or higher than the reference temperature.

[0073] Here, the predetermined reference temperature may be 0 degrees Celsius.

[0074] In other words, comparison is performed to check whether the acquired battery usage environment temperature is less than or higher than the reference temperature of 0 degrees Celsius.

[0075] 2.3. Switch Control Step (S300)

[0076] A switch control step S300 is a step of controlling on/off of the parallel connection switch 200 that controls electrical parallel connection between the first and second battery banks 100a and 100b constituting the E-call battery 100 of the 1S2P structure according to the result of comparison in the reference temperature comparison step S200.

[0077] Specifically, as the result of the comparison, when the acquired battery usage environment temperature is less than the reference temperature of 0 degrees Celsius, the parallel connection switch 200 may be turned on (S310).

[0078] On the other hand, as the result of the comparison, when the acquired battery usage environment temperature is equal to or higher than the reference temperature of 0 degrees Celsius, the parallel connection switch 200 may be turned off (S320).

[0079] Here, the parallel connection switch 200 is initially set to the turn-off state, and the electrical parallel connection between the first and second battery banks 100a and 100b of the E-call battery 100 are cut off and the operation in the 1S1P mode is performed.

[0080] 2.4. Battery Discharging Operation Step (S400)

[0081] A battery discharging operation step S400 is a step of discharging the E-call battery 100 with an electric connection structure corresponding to the control operation of the parallel connection switch 200 in the switch control step S300.

[0082] Specifically, when the parallel connection switch 200 is turned on in the switch control step S300 (S310), the first and second battery banks 100a and 100b of the E-call battery 100 are electrically connected in parallel to each other and are operated in the 1S2P mode (S410).

[0083] On the other hand, when the parallel connection switch 200 is turned off in the switch control step S300 (S320), the electrical parallel connection between the first and second battery banks 100a and 100b of the E-call battery 100 are cut off, and the operation in the 1S1P mode is performed (S420).

[0084] 3. Method for Controlling Operation of E-call Battery in

[0085] Accordance with Exemplary Embodiment (2)

[0086] In another exemplary embodiment according to FIG. 2(b), one of the first and second battery banks 100a and 100b may be selected as a use bank, that is, a battery bank for output by controlling the first and second discharge control switches. The selection of the battery bank for output may be made according to an accumulated use time or a state of charge (SOC) or state of health (SOH) of the battery banks, and in this case, the switch controller transmits a switching control signal to the battery banks. For example, by setting the first battery bank as an output cell when the residual capacity of the first battery bank is greater, and setting the second battery bank as an output cell when the residual capacity of the second battery bank is greater during use, the cell for coping with voltage drop is able to be interchangeably used as the output cell as compared to using only one of the first and second battery banks as the output cell.

[0087] An operation procedure of the battery in accordance with the exemplary embodiment shown in FIG. 2(b) will be described with reference to FIG. 4. The same reference numerals are used for the same parts as in the procedure of FIG. 3.

[0088] 3.1. Temperature Data Acquisition Step (S100)

[0089] A temperature data acquisition step S100 is a step of acquiring battery usage environment temperature data from an external system (not shown) connected to the E-call battery 100 having a 1S2P structure at regular intervals.

[0090] Here, the external system may be a communication system of a vehicle or a small mobile device, or an independent mobile communication device.

[0091] 3.2. Reference Temperature Comparison Step (S200)

[0092] A reference temperature comparison step S200 is a step of comparing a battery usage environment temperature acquired in the temperature data acquisition step S100 with a predetermined reference temperature to check whether the battery usage environment temperature is less than or equal to or higher than the reference temperature.

[0093] Here, the predetermined reference temperature may be 0 degrees Celsius.

[0094] In other words, comparison is performed to check whether the acquired battery usage environment temperature is less than or higher than a predetermined reference temperature, for example, 0 degrees Celsius.

[0095] 3.3. Switch Control Step (S300)

[0096] A switch control step S300 is a step of controlling on/off of the parallel connection switch 200 that controls electrical parallel connection between the first and second battery banks 100a and 100b constituting the E-call battery 100 of the 1S2P structure according to the result of comparison in the reference temperature comparison step S200.

[0097] Specifically, as the result of the comparison, when the acquired battery usage environment temperature is less than the reference temperature of 0 degrees Celsius, the parallel connection switch 200 (Q1) may be turned on (S310). In this case, the first and second discharge control switches 110a and 110b (Q2, Q3) are also turned on, so that the first and second battery banks 100a and 100b may be connected in parallel, and may be driven in the 1S2P mode in a battery discharging operation step to be described later.

[0098] The driving of the battery in the 1S2P mode may be started according to a predetermined E-call mode operation control signal. When the battery usage environment temperature is lower than the predetermined reference temperature at the time of driving in the E-call mode, 1S2P mode driving is performed to improve the low-temperature discharge performance.

[0099] On the other hand, as the result of the comparison, when the acquired battery usage environment temperature is equal to or higher than a predetermined reference temperature, for example, 0 degrees Celsius, the parallel connection switch 200 may be turned off to prepare the 1S1P mode driving (S320).

[0100] In this case, the parallel connection switch 200 is set to the turn-off state, and the electrical parallel connection between the first and second battery banks 100a and 100b of the E-call battery 100 are cut off and the operation in the 1S1P mode is performed in the battery discharging operation step S400 to be described later.

[0101] 3.4. Battery Discharging Operation Step (S400)

[0102] A battery discharging operation step S400 is a step of discharging the E-call battery 100 with an electric connection structure corresponding to the control operation of the parallel connection switch 200 in the switch control step S300.

[0103] 3.4.1. 1S2P Mode Driving Control Step (S410)

[0104] Specifically, when the parallel connection switch 200 is turned on in the switch control step S300 (S310), the first and second battery banks 100a and 100b of the E-call battery 100 are electrically connected in parallel to each other and are operated in the 1S2P mode during the E-call mode (S410). When the mode is not the E-call mode, that is, when the E-call mode operation signal is not received, the process returns to step S100.

[0105] 3.4.2. 1S1P Mode Driving Control Step (S420)

[0106] When the parallel connection switch 200 is turned off in the switch control step S300 (S320), the electrical parallel connection between the first and second battery banks 100a and 100b of the E-call battery 100 are cut off, and the operation in the 1S1P mode is performed during operating in the E-call mode (S420). When the mode is not the E-call mode, that is, when the E-call mode operation signal is not received, the process returns to step S100.

[0107] Meanwhile, in the present exemplary embodiment, before driving in the 1S1P driving mode, a process of deciding which of the first and second battery banks is to be used as the main bank is performed. For example, in the previous steps S200 and S320, when the battery usage environment temperature is not less than a predetermined reference temperature, for example, 0 degrees Celsius, the parallel connection switch 200 (Q1) is turned off, and each of the output terminals the first and second battery banks outputs or blocks the bank voltage to the output terminal P(+) according to the on/off control of the first and second discharge control switches 110a and 110b (Q2 and Q3). In this case, in order to drive in the 1S1P mode, a main use bank output procedure of selecting one of the first and second battery banks 100a and 100b and outputting the voltage of the selected battery bank to the output terminal P(+) is performed, and for selection of the main use bank, the switch controller 500 may select the main use battery through a bank use state determination step (S421), a use bank maintenance step (S422), and a use bank replacement step (S423). In the 1S1P mode, the discharge control switch on the side of the bank determined as the main use bank is turned on so that only the corresponding bank is connected to the output terminal. The main use bank selection step may be implemented through the following procedure.

[0108] (1) Bank Use State Determination Step (S421)

[0109] A determination is made as to whether the accumulated use time of each of the first and second battery banks exceeds a predetermined reference use time. In an exemplary embodiment, for the initial connection state of the battery banks, the on/off state of the switches Q2 and Q3 may be determined so that only one battery bank is a main bank connected to an output terminal, and in this case, a determination is made as to whether the accumulated use time of the main bank exceeds a predetermined reference use time.

[0110] In another exemplary embodiment, in the bank use state determination step S421, the state of charge (SOC) or state of health (SOH) of each battery bank may be calculated, and the use state may be determined by determining whether the calculated value is less than a predetermined reference value.

[0111] In this way, the main use bank may be maintained or selected through additional procedures to be described below, based on at least one calculated value of the accumulated use time or the SOC or SOH of the first or second battery bank, which are calculated according to the bank use state determination.

[0112] In acquiring the accumulated use time, the SOC, and SOH of each battery bank, a well-known technique that is obvious to a person skilled in the art is used.

[0113] (2) Use Bank Maintenance Step (S422)

[0114] When the main bank is determined, and when the accumulated use time of the main bank is less than or equal to a predetermined reference time, the use of the main bank is maintained. That is, the discharge control switch on the side of the main bank is controlled to be on, and the discharge control switch on the other bank side is controlled to be off. When the initial main bank is determined, the main bank discharge control switch is in the on state, and thus the first and second discharge control switches are maintained without the switching operation.

[0115] In another exemplary embodiment, when the charging capacity of the main bank is equal to or greater than a predetermined reference value, the use of the corresponding bank may be maintained. Even in this case, the switching operation of the first and second discharge control switches is not performed.

[0116] (3) Use Bank Replacement Step or Use Bank selection Step (S423)

[0117] When the main bank is determined, and when the accumulated use time of the main bank is greater than the predetermined reference time, the use bank is replaced. Alternatively, when the charging capacity of the main bank is less than the predetermined reference value, the use bank is replaced. The replacement of the use bank is achieved by switching the first and second discharge control switches from on to off or from off to on. In any case, in the 1S1P mode, the parallel connection switch 200 is controlled to be off, and the first and second discharge control switches 110a and 110b are selectively controlled such that one is on and the other is off

[0118] When the main bank is not determined, a bank to be used may be selected according to the control of the switch controller 500. A bank to be used is selected according to the accumulated use time of each battery bank, and the SOC and the SOH of each battery bank acquired in the bank use state determination step S421 above. A criterion for selecting the bank to be used may be to select the one with the smaller accumulated use time or the one with the larger SOC or SOH, between the two battery banks.

[0119] Through the procedures, in the present exemplary embodiment, at a low temperature, the battery bank connected in parallel and used to prevent voltage drop may be used in the 1S1P mode, thereby increasing the operating life of the E-call battery system.

[0120] Meanwhile, in the exemplary embodiments, a battery bank may be a battery module of a single battery cell or of an aggregate of a plurality of battery cells, or a battery pack that is an aggregate of a plurality of battery modules. In addition, although not shown, like a typical battery structure, a battery management system (BMS) for controlling the first and second battery banks may be provided, and the temperature data acquisition controller 300, the comparison controller 400, and the switch controller 500 may be included in the BMS.