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EP-4064513-B1 - BATTERY SYSTEM AND METHOD OF CONTROLLING THE SAME

EP4064513B1EP 4064513 B1EP4064513 B1EP 4064513B1EP-4064513-B1

Inventors

  • HWANG, KUMYUL
  • KIM, WOONGBIN
  • KIM, JUNSEOP
  • JEON, YUJEONG

Dates

Publication Date
20260506
Application Date
20220321

Claims (7)

  1. A battery system, comprising: a battery management module (110) including an external terminal (101a, 101b), a battery terminal (111a, 111b), a heating terminal (112a, 112b), a main switch (114) between the external terminal and the battery terminal, and a heating switch (117) between the external terminal and the heating terminal; at least one battery module (130, 150, 200, 130a) including at least one battery cell (131, 151) connected to the battery terminal, a heating element (132, 152, 250, 300a, 300b, 400a, 400b, 400c, 400d, 132a, 132b) including a first film heater (HR1, HR2, 420a, 420b, 420c, 420d, 132b) and a second film heater (HR3, 410a, 410b, 410c, 410d, 132a) that surrounds at least a portion of the first film heater, a first control switch (134, 134a) between the first film heater of the heating element and the heating terminal (112a), and a second control switch (154, 134b) between the second film heater of the heating element and the heating terminal (112b); and a controller (120, 140, 160) configured to detect connection with a charger (10), and to detect a cell temperature of the at least one battery cell, wherein when the cell temperature is lower than a first reference value, the controller is configured to turn off the main switch, turn on the heating switch and output first and second control signals (141, 161, 141a, 141b) to the first and second control switches to supply heating power from the charger to the first and second film heaters of the heating element, respectively, the second control signal (161, 141b) having a higher duty ratio than a duty ratio of the first control signal (141, 141a), and when the cell temperature is higher than a second reference value, the controller is configured to turn off the heating switch and turn on the main switch to supply charging power from the charger to the at least one battery cell.
  2. The battery system as claimed in claim 1, wherein the controller (120, 140, 160) includes: a microcontroller (120) mounted on the battery management module (110) and configured to control the main switch (114) and the heating switch (117); and at least one analog front end (140, 160) respectively mounted on the at least one battery module (130, 150, 200, 130a) and configured to: detect the cell temperature, transmit the detected cell temperature to the microcontroller, and output the first and second control signals (141, 161, 141a, 141b) to the first and second control switches (134, 154, 134a, 134b), respectively, under control of the microcontroller.
  3. The battery system as claimed in claim 2, wherein: each of the first and second control signals (141, 161) is a pulse width modulation signal, and the microcontroller (120) is configured to determine the duty ratio of the first control signal (141, 141a) and the duty ratio of the second control signal (161, 141b) according to the cell temperature.
  4. The battery system as claimed in any one of the preceding claims, wherein the second reference value is equal to or higher than the first reference value.
  5. A method of controlling the battery system as claimed in any one of the preceding claims, the method comprising: detecting a connection with the charger (10); detecting a cell temperature of the at least one battery cell (130, 150); when the cell temperature is lower than the first reference value, operating the controller (120, 140, 160) to turn off the main switch (114), turn on the heating switch (117) and output first and second control signals (141, 161, 141a, 141b) to the first and second control switches (134, 154, 134a, 134b) so as to supply the heating power from the charger to the first and second film heaters (HR1, HR2, 420a, 420b, 420c, 420d, 132b, HR3, 410a, 410b, 410c, 410d, 132a) of the heating element (132, 152, 250, 300a, 300b, 400a, 400b, 400c, 400d, 132a, 132b), respectively, the second control signal (161, 141b) having a higher duty ratio than a duty ratio of the first control signal (141, 141a); and when the cell temperature is higher than the second reference value, operating the controller to turn off the heating switch and turn on the main switch so as to supply the charging power from the charger to the at least one battery cell.
  6. The method as claimed in claim 5, wherein the supplying of the heating power from the charger to the heating element (132, 152, 250, 300a, 300b, 400a, 400b, 400c, 400d, 132a, 132b) includes: detecting the cell temperature that is lower than the first reference value; turning off the main switch (114); requesting the charger to output a heating voltage; detecting the heating voltage applied to the external terminal (101a, 101b); turning on the heating switch (117); and adjusting a duty ratio of a control signal (141, 161, 141a, 141b) for controlling the control switch (134, 154, 134a, 134b).
  7. The method as claimed in claim 5 or 6, wherein the supplying of the charging power from the charger to the at least one battery cell (131, 151) includes: detecting that the cell temperature is maintained to be higher than the second reference value for a preset time; turning off the heating switch (117); requesting the charger to output a charging voltage; detecting the charging voltage applied to the external terminal (101a, 101b); and turning on the main switch (114).

Description

BACKGROUND 1. Field One or more embodiments relate to a battery system and a method of controlling the same. 2. Description of the Related Art Lead-acid batteries may be used in light electric vehicles (LEVs) such as golf carts, industrial cleaners, forklifts, and aerial work platforms, but lithium-ion batteries instead of lead-acid batteries are used to address environmental problems and for increased energy efficiency. Due to the nature of a product operating in an outdoor environment, LEVs should be reliable in low and high temperature environments ranging from about -40°C to 40°C. Also, fast charging at 1C-rate or higher may be desirable to enhance the usability of the product. US 2021/0036388 A1 discloses a battery heating system and method, the system including a temperature sampling module, a control module and a heating module. SUMMARY In accordance with an aspect of the present invention, there is provided a battery system as set out in claim 1. Embodiments of the invention are set out in the dependent claims. The controller may include: a microcontroller mounted on the battery management module and configured to control the main switch and the heating switch; and at least one analog front end respectively mounted on the at least one battery module and configured to detect the cell temperature, transmit the detected cell temperature to the microcontroller, and output a control signal to the control switch according to control of the microcontroller. The control signal may be a pulse width modulation signal, and the microcontroller may be configured to determine a duty ratio of the control signal according to the cell temperature. The second reference value may be equal to or higher than the first reference value. Embodiments of the invention are also directed to a method of controlling the battery system of claim 1. The supplying of the heating power from the charger to the heating element may include: detecting the cell temperature that is lower than the first reference value; turning off the main switch; requesting the charger to output a heating voltage; detecting the heating voltage applied to the external terminal; turning on the heating switch; and adjusting a duty ratio of a control signal for controlling the control switch. The supplying of the charging power from the charger to the at least one battery cell may include: detecting that the cell temperature is maintained to be higher than the second reference value for a preset time; turning off the heating switch; requesting the charger to output a charging voltage; detecting the charging voltage applied to the external terminal; and turning on the main switch. BRIEF DESCRIPTION OF THE DRAWINGS Features will become apparent to those of skill in the art by describing in detail example embodiments with reference to the attached drawings in which: FIG. 1 illustrates a battery system according to an example embodiment;FIG. 2 illustrates a battery system according to another example embodiment;FIG. 3 illustrates a battery module according to an example embodiment;FIG. 4A illustrates a film heater according to an example embodiment;FIG. 4B illustrates a film heater according to another example embodiment;FIGS. 5A through 5D illustrate heating elements according to example embodiments;FIG. 6 illustrates a battery module including the heating element of FIGS. 5A through 5D, according to an example embodiment;FIG. 7 is a flowchart for describing a method of controlling a battery system according to an example embodiment; andFIG. 8 is a flowchart for describing a method of controlling a battery system according to another example embodiment. DETAILED DESCRIPTION Example embodiments will now be described more fully hereinafter with reference to the accompanying drawings; however, they may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey example implementations to those skilled in the art. In the following, those embodiments that do not fall within the scope of the claims relates to exemplary embodiments of the disclosure that are not covered by the claimed invention. In the figures, the dimensions of layers and regions may be exaggerated for clarity of illustration. It will also be understood that when a layer or element is referred to as being "on" another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may also be present. Further, it will be understood that when a layer is referred to as being "under" another layer, it can be directly under, and one or more intervening layers may also be present. In addition, it will also be understood that when a layer is referred to as being "between" two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present. Like reference numerals refer to