Single battery temperature detection device

Abstract

The utility model discloses a single battery temperature detection device, which comprises an MCU chip and an AFE chip which are in communication connection, and further comprises measuring circuits which are in one-to-one correspondence connection with temperature sensors, and further comprises a plurality of alternative analog switches, every two measuring circuits correspond to one alternative analog switch and one GPIO (General Purpose Input / Output) channel of the AFE chip; two input channels of each alternative analog switch are electrically connected with the output ends of the two corresponding measuring circuits respectively, and the output end of each alternative analog switch is electrically connected with the corresponding GPIO channel respectively; and one digital output port of the MCU chip is connected with the gating control ends of all the alternative analog switches. According to the utility model, double channel expansion can be realized through the plurality of alternative analog switches, 1 / 2 temperature measurement channels can be realized each time, the measurement efficiency is improved, and meanwhile, the device also has the advantages of simple control logic, high GPIO (General Purpose Input / Output) channel utilization rate and the like.

Description

Technical Field

[0001] The utility model belongs to the field of battery thermal management, and in particular relates to a single cell temperature detection device used in a battery management system. Background Art

[0002] Lithium batteries generate a certain amount of heat when reacting, but usually the temperature difference between the battery and the environment is not large. If the temperature of a single battery is much higher than the ambient temperature and the temperature of other single batteries, it means that there may be a fault inside the battery. The cause of the fault must be determined and handled in time. Therefore, when detecting the battery temperature in the energy storage PACK box, each single battery needs to be tested separately.

[0003] As more and more single cells are integrated into the energy storage PACK, the number of single cell temperatures that need to be detected also increases. Currently, single cell temperature detection is mainly based on NTC, which uses a resistor voltage divider, and voltage value acquisition mainly relies on the GPIO channel measurement of the AFE chip (GPIO channels can be used as AD). The ratio of the number of battery cell voltage measurement channels to GPIO channels of mainstream AFE chips is mostly 2:1 (for example, there are 18 battery cell voltage measurement channels and 9 GPIO measurement channels). Some actual ratios are even higher, so the number of battery cell voltage measurement channels that can be connected needs to be expanded.

[0004] In the prior art, the expansion method of the battery cell temperature measurement channel is to use multiple multi-channel analog switches (multiple selections), and the address lines of the multi-channel analog switches are controlled by the GPIO channels of the AFE. Figure 1 As shown in the figure, this method can only measure 1 / n temperature measurement channels at most each time, and needs to be measured n times, which has low measurement efficiency. During measurement, the MCU also needs to continuously send analog switch selection instructions to the AFE, which increases the complexity of control logic and code. Utility Model Content

[0005] The utility model provides a single cell temperature detection device, the purpose of which is to solve the problems of low temperature measurement efficiency and complex gating control.

[0006] The technical solution of this utility model is as follows:

[0007] A single cell temperature detection device comprises an MCU chip and an AFE chip which are communicatively connected, and also comprises a measurement circuit which is connected to the temperature sensor in a one-to-one correspondence, and the single cell temperature detection device also comprises a plurality of two-choice analog switches;

[0008] Each two measurement circuits correspond to a two-to-one analog switch and a GPIO channel of the AFE chip; the two input channels of each two-to-one analog switch are electrically connected to the output ends of the two corresponding measurement circuits, and the output ends of each two-to-one analog switch are electrically connected to the corresponding GPIO channels;

[0009] A digital output port of the MCU chip is connected to the enable control terminals of all the two-to-one analog switches.

[0010] As a further improvement of the single cell temperature detection device: the digital output port is connected to the input end of the digital isolator, and the output end of the digital isolator is connected to the enable control end of all the two-to-one analog switches.

[0011] Compared with the prior art, the utility model has the following positive effects:

[0012] 1. The utility model can achieve 2-fold channel expansion through multiple two-choice analog switches, and can achieve 1 / 2 temperature measurement channels each time, thereby improving measurement efficiency.

[0013] 2. The utility model synchronously controls the selection channels of all two-choice analog switches through the digital output terminal of the MCU, and the control logic is simple. Moreover, the selection of the channel only occupies the pin of one MCU chip and does not occupy the GPIO channel. The saved GPIO channel can be used to expand the temperature measurement channel, thereby improving the utilization rate of the GPIO channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a circuit principle diagram of a single cell temperature detection device in the prior art;

[0015] Figure 2 This is a circuit schematic diagram of the utility model. DETAILED DESCRIPTION

[0016] The technical solution of the utility model is described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the utility model, rather than all the embodiments.

[0017] like Figure 2 A single cell temperature detection device includes an MCU chip and an AFE chip connected by daisy chain communication, and also includes a measurement circuit whose input end is connected to the temperature sensor in a one-to-one correspondence. The number of the measurement circuit and the temperature sensor is 2n.

[0018] The single cell temperature detection device also includes n two-to-one analog switches (U1, U2...Un). Every two measurement circuits correspond to one two-to-one analog switch and one GPIO channel of the AFE chip. The two input channels (A1 and A2) of each two-to-one analog switch are respectively electrically connected to the output ends of the two corresponding measurement circuits, and the output end B of each two-to-one analog switch is respectively electrically connected to the corresponding GPIO channel. A total of 2n measurement circuits / temperature sensors can be connected through n two-to-one analog switches, and n GPIO channels are occupied.

[0019] A digital output port (including an IO port with input and output functions) of the MCU chip is connected to the input end of the digital isolator, and the output end of the digital isolator is simultaneously connected to the strobe control end of all the two-to-one analog switches, so as to control the synchronous strobe channels of all the two-to-one analog switches.

[0020] The specific measurement process is as follows:

[0021] 1) The MCU chip sets the GPIO channel of the AFE chip as an analog channel;

[0022] 2) The digital output port used to select the channel on the MCU chip is set low or high to select the A1 channel of each two-to-one analog switch;

[0023] 3) The MCU chip controls the AFE chip to start measurement;

[0024] 4) The MCU chip reads the conversion values ​​of n GPIO channels;

[0025] 5) The digital output port of the MCU chip is set high or low to select the A2 channel of each two-to-one analog switch;

[0026] 6) The MCU chip controls the AFE chip to start measurement;

[0027] 7) The MCU chip reads the conversion values ​​of n GPIO channels;

[0028] 8) At this point, all 2n temperature channels in this round have been measured. Repeat steps 2) to 7) to measure the temperature in real time.

[0029] It should be noted that it is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. The scope of the present invention is defined by the claims rather than the above description.

Claims

1. A single cell battery temperature detection device, comprising an MCU chip and an AFE chip connected in communication, and also comprising a measurement circuit connected in a one-to-one correspondence with the temperature sensor, characterized in that: The single cell temperature detection device also includes a plurality of two-to-one analog switches; Each two measurement circuits correspond to a two-to-one analog switch and a GPIO channel of the AFE chip; the two input channels of each two-to-one analog switch are electrically connected to the output ends of the two corresponding measurement circuits, and the output ends of each two-to-one analog switch are electrically connected to the corresponding GPIO channels; A digital output port of the MCU chip is connected to the enable control terminals of all the two-to-one analog switches.

2. The single cell battery temperature detection device according to claim 1, characterized in that: The digital output port is connected to the input end of the digital isolator, and the output end of the digital isolator is connected to the strobe control end of all the two-to-one analog switches.

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