JP-2026075367-A - Recharge control device for secondary batteries

Abstract

[Problem] To provide a secondary battery charging control device that can efficiently warm up and charge the entire battery pack, which is composed of multiple secondary batteries, according to the charging settings. [Solution] The charging control device 40 comprises a battery temperature sensor 11, a battery temperature control device 20, a DC-DC converter 4, a BECM 10, and a PCM 14. The battery temperature sensor 11 and the DC-DC converter 4 are provided for each of the multiple battery modules. The BECM 10 and the PCM 14 determine the warm-up order of the multiple battery modules to maximize the charging demands of the multiple battery modules under predetermined setting conditions, if there are previous battery modules with a temperature lower than the first temperature T1. Furthermore, they control the DC-DC converter 4 to simultaneously charge the multiple battery modules with a maximum current value set based on their respective temperatures. [Selection Diagram] Figure 2

Inventors

• 森島 千菜美
• 山賀 勇真
• 種平 貴文
• 大路 潔
• ▲徳▼田 大樹

Assignees

• マツダ株式会社

Dates

Publication Date

20260508

Application Date

20241022

Claims (11)

1. A charging control device for secondary batteries that make up a battery pack, The multiple secondary batteries included in the aforementioned battery pack are connected in parallel during operation. The charging control device is Each of the multiple secondary batteries is provided with a battery temperature detection means for detecting the temperature of the secondary battery, A battery temperature control device that can switch the secondary battery to be warmed up, A charging current adjustment device is provided for each of the multiple secondary batteries, and is capable of adjusting the charging current to decrease as the temperature of the secondary battery decreases. The system includes a control device that controls the battery temperature adjustment device and the charging current adjustment device, respectively. The control device is A secondary battery charging control device characterized in that, when there are multiple secondary batteries among the multiple secondary batteries whose temperature is lower than a first temperature which is the warm-up completion temperature, it determines the order in which to warm up the multiple secondary batteries in order to maximize the demand for charging as a battery pack under predetermined setting conditions, and controls the charging current adjustment device to perform charging simultaneously and at the same time as the start of the first warm-up with a maximum current value set based on each temperature.
2. In the charging control device for a secondary battery according to claim 1, The charging control device further comprises an SOC determination unit that determines the SOC in each of the plurality of secondary batteries, The charging current adjustment device is capable of adjusting the charging current according to the temperature and the state of temperature (SOC), and is characterized in that it can adjust the charging current to decrease as the SOC of the secondary battery increases.
3. In the charging control device for a secondary battery according to claim 1, If the setting condition is the target charging time, and the request regarding charging is to maximize the charge amount of the battery pack, The charging control device for a secondary battery is characterized in that the control device controls the battery temperature control device so as to prioritize warming up the secondary battery on the side with the higher temperature.
4. In the charging control device for a secondary battery according to claim 3, If there is a secondary battery whose temperature is equal to or higher than the first temperature, A secondary battery charging control device characterized in that the control device controls the battery temperature adjustment device so that it prioritizes warming up the secondary battery with the highest temperature among the secondary batteries whose temperature is lower than the first temperature.
5. In the charging control device for a secondary battery according to claim 1, If the setting condition is the target charging time, and the request regarding charging is to maximize the amount of charge of the battery pack, A secondary battery charging control device characterized in that the control device changes the warm-up completion temperature of the secondary battery so as to maximize the amount of charge as a battery pack at the target charging time.
6. In the charging control device for a secondary battery according to claim 1, If the setting condition is the target SOC, and the request regarding charging is to minimize the charging time of the battery pack until the target SOC is reached, The charging control device for a secondary battery is characterized in that the control device controls the battery temperature control device so as to prioritize warming up the secondary battery on the side with the higher temperature.
7. In the charging control device for a secondary battery according to claim 6, If there is a secondary battery whose temperature is equal to or higher than the first temperature, A secondary battery charging control device characterized in that the control device controls the battery temperature adjustment device so that it prioritizes warming up the secondary battery with the highest temperature among the secondary batteries whose temperature is lower than the first temperature.
8. In the charging control device for a secondary battery according to claim 1, If the setting condition is the target SOC, and the request regarding charging is to minimize the charging time of the battery pack until the target SOC is reached, The control device is characterized by changing the warm-up completion temperature of the secondary battery in order to minimize the charging time in the battery pack.
9. In the charging control device for a secondary battery according to claim 1, The charging control device for a secondary battery is characterized in that the control device performs a predictive calculation of a value related to the request based on a plurality of parameters relating to the plurality of secondary batteries, and derives the warm-up sequence and the warm-up completion temperature of the plurality of secondary batteries.
10. In the charging control device for a secondary battery according to claim 9, The multiple parameters include at least the initial temperature, initial SOC, heating amount, and target charging time of the multiple secondary batteries. The control device is The warm-up completion temperature of the secondary battery is varied, and the final charge amount is calculated for cases where the secondary battery on the high-temperature side is warmed up and cases where the secondary battery on the low-temperature side is warmed up, and these final charge amounts are compared. A secondary battery charging control device characterized by determining the warm-up sequence of the secondary battery that will result in the largest final charge, and controlling the battery temperature control device to warm up the battery in accordance with the warm-up sequence.
11. In the charging control device for a secondary battery according to claim 9, The multiple parameters include at least the initial temperature, initial SOC, heating amount, and target SOC of the multiple secondary batteries. The control device is The warm-up completion temperature of the secondary battery is varied, and the charging time required is calculated for cases where the secondary battery on the high-temperature side is warmed up first and for cases where the secondary battery on the low-temperature side is warmed up first, and these charging times are compared. A secondary battery charging control device characterized by determining the warm-up sequence of the secondary battery that results in the shortest charging time, and controlling the battery temperature control device to warm up the battery in the order described above.

Description

This disclosure relates to a charging control device for a secondary battery. Conventionally, electric vehicles are known, which are vehicles that are powered by electricity supplied from multiple secondary batteries (hereinafter sometimes simply referred to as batteries) and run on the power supplied by these batteries. Furthermore, various technologies have been proposed for charging multiple secondary batteries in a short time (see, for example, Patent Document 1). Patent Document 1 discloses a configuration for charging multiple secondary batteries by staggering the heating timing and charging timing of the batteries according to their temperatures. This method shortens the total charging time. Japanese Patent Publication No. 2023-101151 This is a schematic diagram of the main part of the high-voltage circuit of the vehicle according to Embodiment 1.This is a functional block diagram showing the configuration of the vehicle's charging control device.This is a schematic diagram of a battery module including a battery temperature control device.This is a schematic diagram showing the relationship between SOC and charging current in a battery module.This flowchart shows the first battery charging control procedure and warm-up control procedure.This is a flowchart of subprocess A.This is a flowchart of subprocess B.This is a flowchart of subprocess C.This is a flowchart of subprocess D.This is a flowchart of subprocess E.This is a flowchart of subprocess F.This is a flowchart showing the second charging control procedure for the battery.This is a flowchart showing the second warm-up control procedure for the battery, corresponding to the second charge control procedure.This is a flowchart of subprocess G.This is a flowchart of subprocess H.This is a flowchart of subprocess I.This is a schematic diagram showing the procedure for determining the battery warm-up sequence and the procedure for extracting the warm-up completion temperature.This flowchart shows the procedure for calculating the predicted charge amount at a given time.This figure shows the time-series change in SOC when the warm-up completion temperature and warm-up sequence are changed.This figure shows the time change in battery temperature when the high-temperature battery module is warmed up first.This figure shows the time-series change of SOC when the high-temperature battery module is warmed up first.This is a schematic diagram of another battery module, including a battery temperature control device.This figure shows the differences between the battery charging control procedure according to Embodiment 2 and the battery charging control procedure according to Embodiment 1.This figure shows the differences between the battery warm-up control procedure according to Embodiment 2 and the battery warm-up control procedure according to Embodiment 1.This flowchart shows the procedure for predicting the charging time until the target SOC is reached.This figure shows the time-series change in the SOC of battery modules A and B when the high-temperature battery module is warmed up first. The embodiments of this disclosure will be described below with reference to the drawings. The following description of preferred embodiments is illustrative in nature and is not intended to limit this disclosure, its applications, or its uses. (Embodiment 1) [1: Configuration of key components of electrical circuits in vehicles] Figure 1 is a schematic diagram of the main part of the high-voltage circuit of the vehicle according to Embodiment 1. Figure 2 is a functional block diagram showing the configuration of the charging control device. For the sake of explanation, in Figures 1 and 2, electrical components and control circuits that are not directly related to the battery modules 2A and 2B are not shown or described. As shown in Figure 1, the high-voltage circuit in vehicle 1 includes two sets of battery modules 2A and 2B, two sets of DC-DC converters 4A and 4B, two sets of circuit changeover switches 7A and 7B, an inverter 5, and a motor 6. In the following description, battery modules 2A and 2B may be referred to as mod(A) and mod(B). Furthermore, mod(A), mod(B), or multiple battery modules may be collectively referred to simply as batteries or secondary batteries. When vehicle 1 is running, both circuit selector switches 7A and 7B are closed. Mod(A) and mod(B) are connected to inverter 5, and their respective voltages are adjusted by DC-DC converters 4A and 4B before being input to inverter 5. The DC power input to inverter 5 is converted to AC power, which becomes the driving power for motor 6. Driving motor 6 causes vehicle 1 to move. Note that the voltages of mod(A) and mod(B) when fully charged are approximately several hundred volts. On the other hand, when charging mod(A) and mod(B), both circuit selector switches 7A and 7B are opened, electrically connecting mod(A) and mod(B) to the rapid charger 31 provided in the charging equipment 30. mod(A) and mod