CN113949136A

CN113949136A - Lithium battery pack management chip, method and system

Info

Publication number: CN113949136A
Application number: CN202111311168.0A
Authority: CN
Inventors: 不公告发明人
Original assignee: Zhuhai Maiju Microelectronics Co Ltd
Current assignee: Zhuhai Maiju Microelectronics Co Ltd
Priority date: 2020-11-24
Filing date: 2021-11-08
Publication date: 2022-01-18
Also published as: CN112398199A

Abstract

The utility model provides a lithium cell group management chip, lithium cell group include a plurality of lithium cell monomer of series connection, include: the multiplexing unit is controlled to respectively collect the battery voltage of one lithium battery cell in the N lithium battery cells; an analog-to-digital conversion unit receiving the battery voltage and converting the battery voltage into a digital signal; a first filtering unit for performing filtering processing on the digital signal and generating a filtered signal; the comparison and conversion unit is used for comparing the filtered signal with a preset voltage threshold so as to generate state information; the state filtering unit converts the state information into a voltage state signal; and the switch control module is used for generating control signals of a charging switch and a discharging switch of the lithium battery pack based on the voltage state signal so as to control the on and off of the charging switch and the discharging switch, thereby controlling the charging and discharging of the lithium battery pack. The disclosure also provides a lithium battery pack management method, a lithium battery pack management system and electric equipment.

Description

Lithium battery pack management chip, method and system

Technical Field

The disclosure relates to a lithium battery pack management chip, a method, a system and an electric device.

Background

The lithium battery has high requirements on charging and discharging, and when overcharge, overdischarge, overcurrent, short circuit and the like occur, the internal pressure of the lithium battery is greatly increased due to heat, and sparks, combustion and even explosion are easily generated. Therefore, overcharge and overdischarge protection of the lithium battery pack is necessary.

At present, for a low-cost independent lithium battery management chip (without an upper computer), a plurality of analog comparators are generally used for sampling battery voltage, and battery charging and discharging control is completed by comparing information such as discharging current and temperature with a threshold value configured by a user. The more flexible the user configuration support, the more complex the comparator reference voltage generation circuit, and the greater the power consumption that results.

Also, since the analog comparator can only output a single bit of information, more complicated post-processing algorithms are limited from being applied.

Disclosure of Invention

In order to solve one of the above technical problems, the present disclosure provides a lithium battery pack management chip, a method, a system and an electrical device.

According to an aspect of the present disclosure, a lithium battery pack management chip, the lithium battery pack includes N lithium battery cells connected in series, and the lithium battery pack management chip includes:

a multiplexing unit controlled to collect a battery voltage of one lithium battery cell of the N lithium battery cells, respectively;

an analog-to-digital conversion unit that receives the battery voltage and converts the battery voltage into a digital signal;

a first filtering unit for performing filtering processing on the digital signal and generating a filtered signal;

the comparison and conversion unit is used for comparing the filtered signal with a preset voltage threshold so as to generate state information;

a state filtering unit that converts the state information into a voltage state signal; and

the switch control module generates control signals of a charging switch and a discharging switch of the lithium battery pack based on the voltage state signal so as to control the on and off of the charging switch and the discharging switch, and therefore the charging and discharging of the lithium battery pack are controlled.

According to at least one embodiment of the present disclosure, the battery voltage of one lithium battery of the multiplexing unit is received, and the battery voltage is amplified to generate an amplified signal, and the amplified signal is provided to the analog-to-digital conversion unit.

According to at least one embodiment of the present disclosure, the first filtering units are FIR filters and the number of the first filtering units is N, and each of the N first filtering units is configured to perform filtering processing on the digital signal generated by the battery voltage of each of the N lithium battery cells collected by the multiplexing unit.

According to at least one embodiment of the present disclosure, the number of the comparison and conversion units is N, and each of the N comparison and conversion units is configured to receive the filtered signal output by each of the N first filtering units, respectively.

According to at least one embodiment of the present disclosure, the number of the state filtering units is N, and each of the N state filtering units is configured to receive the state information output by each of the N comparison and conversion units, respectively.

According to at least one embodiment of the present disclosure, the preset voltage threshold includes an over-voltage threshold and an under-voltage threshold, and the filtered signal is compared with the over-voltage threshold and the under-voltage threshold, respectively, so as to convert the filtered signal into status information.

According to at least one embodiment of the present disclosure, the status information is single-bit status information.

According to at least one embodiment of the present disclosure, the voltage status signal includes an over-voltage status signal and an under-voltage status signal.

According to at least one embodiment of the present disclosure, the apparatus further comprises a gain control module, wherein the gain control module is configured to adjust an amplification gain factor of the signal amplification unit.

According to at least one embodiment of the present disclosure, the number of the signal amplifying units and the analog-to-digital converting units is one.

According to at least one embodiment of the present disclosure, the apparatus further includes an equalization determination module, where the equalization determination module is configured to receive the filtered signal output by the first filtering unit, so as to determine an equalization condition of the battery voltages of the N lithium battery cells.

According to at least one embodiment of the present disclosure, the temperature sensing unit is configured to detect a temperature of a lithium battery pack to generate a temperature voltage value, acquire the temperature voltage value of the temperature sensing unit by controlling the multiplexing unit, and amplify the temperature voltage value by the signal amplifying unit to generate an amplified temperature voltage signal, the analog-to-digital converting unit is configured to receive the amplified temperature voltage signal and output the amplified temperature voltage signal to the N +1 th first filter for filtering to generate a filtered temperature voltage signal, the N +1 th comparing and converting unit is configured to compare the filtered temperature voltage signal with a preset temperature threshold value to generate temperature state information, the (N + 1) th state filtering unit converts the temperature state information into a temperature state signal, and the switch control module controls the on and off of the charging switch and the discharging switch according to the temperature state signal.

According to at least one embodiment of the present disclosure, the preset temperature threshold includes a charging low temperature threshold, a charging high temperature threshold, a discharging low temperature threshold, and a discharging high temperature threshold, and the filtered temperature voltage signal is respectively compared with the charging low temperature threshold, the charging high temperature threshold, the discharging low temperature threshold, and the discharging high temperature threshold according to a charging and discharging state of the lithium battery pack.

According to at least one embodiment of the present disclosure, the temperature status signal includes a low temperature state of charge, a high temperature state of charge, a low temperature state of discharge, and a high temperature state of discharge.

According to at least one embodiment of the present disclosure, the lithium battery pack further includes a current sensing unit, an N +1 th first filter, an N +1 th comparison and conversion unit, and a state filtering group, the current sensing unit is configured to detect a charge and discharge current of the lithium battery pack to generate a first voltage value representing the charge and discharge current, acquire the first voltage value of the current sensing unit by controlling the multiplexing unit, amplify the first voltage value by the signal amplifying unit to generate an amplified first voltage signal, the analog-to-digital conversion unit receives the amplified first voltage signal and outputs the amplified first voltage signal to the N +1 th first filter to be filtered to generate a filtered first voltage signal, and the N +1 th comparison and conversion unit is configured to compare the filtered first voltage signal with a preset current voltage threshold, the state filtering group converts the current state information into a current state signal, and the switch control module controls the on and off of the charging switch and the discharging switch according to the current state signal.

According to at least one embodiment of the present disclosure, the state filter bank includes a plurality of state filters corresponding to different current thresholds and response times such that the response time is shorter as the charge and discharge current is larger.

According to at least one embodiment of the present disclosure, the state filtering unit includes a state register and a counter, when the state information received by the state filtering unit is opposite to the state information registered by the state register, the counter is incremented by 1, otherwise, the counter is cleared, and when the counter is incremented to a specified response time threshold, the state register is inverted.

According to at least one embodiment of the present disclosure, the first filtering unit is an FIR filter.

According to at least one embodiment of the present disclosure, the system further includes an equalization determination module, a first median filter, and a kalman filter, where the first median filter receives a digital signal from the analog-to-digital conversion unit, performs median filtering, the processed signal is provided to the kalman filter for processing, the signal processed by the kalman filter is provided to the equalization determination module, and the equalization determination module determines an equalization condition of the battery voltage of the N lithium battery cells according to the received signal.

According to at least one embodiment of the present disclosure, the apparatus further includes a current sensing unit, a second comparison and conversion unit, and a state filtering group, wherein the current sensing unit is configured to detect a charge and discharge current of the lithium battery pack to generate a first voltage value representing the charge and discharge current, and collect a first voltage value of the current sensing unit by controlling the multiplexing unit, and amplify the first voltage value by the signal amplifying unit to generate an amplified first voltage signal, the analog-to-digital conversion unit receives the amplified first voltage signal and outputs the amplified first voltage signal to the second comparison and conversion unit, the second comparison and conversion unit is configured to compare the filtered first voltage signal with a preset current-to-voltage threshold value to generate current state information, and the state filtering group converts the current state information into a current state signal, and the switch control module controls the on and off of the charging switch and the discharging switch according to the current state signal.

According to at least one embodiment of the present disclosure, the temperature sensing unit is configured to detect a temperature of a lithium battery pack to generate a temperature voltage value, collect the temperature voltage value of the temperature sensing unit by controlling the multiplexing unit, amplify the temperature voltage value by the signal amplifying unit to generate an amplified temperature voltage signal, receive the amplified temperature voltage signal and output the amplified temperature voltage signal to the second median filter for filtering to generate a filtered temperature voltage signal, compare the filtered temperature voltage signal with a preset temperature threshold value to generate temperature state information, and convert the temperature state information into a temperature state signal by the second state filtering unit, and the switch control module controls the on and off of the charging switch and the discharging switch according to the temperature state signal.

According to at least one embodiment of the present disclosure, the lithium battery pack further includes a battery open circuit detection unit, the battery open circuit detection unit includes N capacitors, each capacitor of the N capacitors is connected in parallel with each lithium battery cell of the N lithium battery cells, each capacitor is charged after being discharged, a battery voltage of each lithium battery cell is obtained by measuring a voltage across each capacitor, and open circuit detection is performed according to the battery voltage.

According to at least one embodiment of the present disclosure, the lithium battery pack further includes a current analog-to-digital conversion unit, a current sensing unit, a second comparison conversion unit, and a state filtering group, wherein the current sensing unit is configured to detect a charge and discharge current of the lithium battery pack to generate a first voltage value representing the charge and discharge current, and collect the first voltage value of the current sensing unit by controlling the multiplexing unit, and amplify the first voltage value by the signal amplifying unit to generate an amplified first voltage signal, the current analog-to-digital conversion unit receives the amplified first voltage signal and outputs the amplified first voltage signal to the second comparison conversion unit, the second comparison conversion unit is configured to compare the filtered first voltage signal with a preset current voltage threshold to generate current state information, and the state filtering group converts the current state information into a current state signal, and the switch control module controls the on and off of the charging switch and the discharging switch according to the current state signal.

According to at least one embodiment of the present disclosure, the lithium battery pack further includes a current sensing unit, an overcurrent comparator, a second comparison and conversion unit, and a state filtering group, wherein the current sensing unit is configured to detect a charge and discharge current of the lithium battery pack to generate a first voltage value representing the charge and discharge current, and collect the first voltage value of the current sensing unit by controlling the multiplexing unit, and amplify the first voltage value by the signal amplifying unit to generate an amplified first voltage signal, the analog-to-digital conversion unit receives the amplified first voltage signal and outputs the amplified first voltage signal to the second comparison and conversion unit, the second comparison and conversion unit is configured to compare the filtered first voltage signal with a preset current-to-voltage threshold value to generate current state information, and the state filtering group converts the current state information into a current state signal, the switch control module controls the charging switch and the discharging switch to be switched on and off according to the current state signal, wherein the overcurrent comparator is used for comparing the charging and discharging current detected by the current sensing unit with a preset current voltage threshold value to judge whether the charging and discharging current is greater than the preset current voltage threshold value, and if the charging and discharging current is greater than the preset current voltage threshold value, the analog-to-digital conversion unit is controlled to shorten the sampling period of the analog-to-digital conversion unit.

According to another aspect of the present disclosure, a lithium battery pack management method includes N lithium battery cells connected in series, including:

the multiplexing unit is controlled so as to respectively collect the battery voltage of one lithium battery cell in the N lithium battery cells;

receiving the battery voltage through an analog-to-digital conversion unit and converting the battery voltage into a digital signal;

the first filtering unit is used for filtering the digital signal and generating a filtered signal;

converting the state information into a voltage state signal through a state filtering unit; and

and generating control signals of a charging switch and a discharging switch of the lithium battery pack through a switch control module based on the voltage state signal so as to control the on and off of the charging switch and the discharging switch, thereby controlling the charging and discharging of the lithium battery pack.

According to at least one embodiment of the present disclosure, the method further includes receiving, by a signal amplification unit, a battery voltage of one lithium battery from the multiplexing unit, and amplifying the battery voltage to generate an amplified signal, which is provided to the analog-to-digital conversion unit.

According to at least one embodiment of the present disclosure, the method further comprises adjusting an amplification gain factor of the signal amplification unit.

According to at least one embodiment of the present disclosure, the method further includes receiving the filtered signal output by the first filtering unit to determine a balancing condition of the battery voltages of the N lithium battery cells.

According to at least one embodiment of the present disclosure, the method further comprises detecting the temperature of the lithium battery pack by a temperature sensing unit to generate a temperature voltage value and collecting the temperature voltage value of the temperature sensing unit by controlling the multiplexing unit, and the temperature voltage value is amplified by the signal amplifying unit to generate an amplified temperature voltage signal, the analog-to-digital conversion unit receives the amplified temperature voltage signal and outputs the amplified temperature voltage signal to the (N + 1) th first filter for filtering so as to generate a filtered temperature voltage signal, the (N + 1) th comparison and conversion unit is used for comparing the filtered temperature voltage signal with a preset temperature threshold value, so as to generate temperature state information, the (N + 1) th state filtering unit converts the temperature state information into a temperature state signal, and the switch control module controls the on and off of the charging switch and the discharging switch according to the temperature state signal.

According to at least one embodiment of the present disclosure, the method further includes detecting, by a current sensing unit, a charge and discharge current of the lithium battery pack to generate a first voltage value representing the charge and discharge current, acquiring, by controlling the multiplexing unit, the first voltage value of the current sensing unit, and amplifying, by the signal amplifying unit, the first voltage value to generate an amplified first voltage signal, receiving, by the analog-to-digital converting unit, the amplified first voltage signal and outputting the amplified first voltage signal to an N +1 th first filter for filtering to generate a filtered first voltage signal, comparing, by an N +1 th comparing and converting unit, the filtered first voltage signal with a preset current-to-voltage threshold to generate current state information, and converting, by a state filtering group, the current state information into a current state signal, and the switch control module controls the on and off of the charging switch and the discharging switch according to the current state signal.

According to still another aspect of the present disclosure, a lithium battery pack management system includes:

the lithium battery pack management chip is at least used for detecting the battery voltage of each lithium battery cell in the N lithium battery cells of the lithium battery pack; and

the lithium battery pack management chip controls the on and off of the charging switch and the discharging switch according to the detected battery voltage.

According to yet another aspect of the disclosure, an electrical device comprises:

a lithium battery pack;

the lithium battery pack management system is used for controlling the charging and discharging of the lithium battery pack; and

a powered device connected to the lithium battery pack to provide power through the lithium battery pack.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the disclosure and together with the description serve to explain the principles of the disclosure.

Fig. 1 shows a schematic diagram of a lithium battery pack management chip according to one embodiment of the present disclosure.

Fig. 2 shows a schematic diagram of a lithium battery pack management chip according to one embodiment of the present disclosure.

Fig. 3 shows a schematic diagram of a lithium battery pack management chip according to one embodiment of the present disclosure.

Fig. 4 illustrates a flow chart of a lithium battery pack management method according to one embodiment of the present disclosure.

Fig. 5 illustrates a flow chart of a lithium battery pack management method according to one embodiment of the present disclosure.

Fig. 6 illustrates a flow chart of a lithium battery pack management method according to one embodiment of the present disclosure.

Fig. 7 shows a schematic diagram of a state filter according to one embodiment of the present disclosure.

Fig. 8 shows a schematic diagram of an electrical device according to an embodiment of the present disclosure.

Detailed Description

The present disclosure will be described in further detail with reference to the drawings and embodiments. It is to be understood that the specific embodiments described herein are for purposes of illustration only and are not to be construed as limitations of the present disclosure. It should be further noted that, for the convenience of description, only the portions relevant to the present disclosure are shown in the drawings.

It should be noted that the embodiments and features of the embodiments in the present disclosure may be combined with each other without conflict. Technical solutions of the present disclosure will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

Unless otherwise indicated, the illustrated exemplary embodiments/examples are to be understood as providing exemplary features of various details of some ways in which the technical concepts of the present disclosure may be practiced. Accordingly, unless otherwise indicated, features of the various embodiments may be additionally combined, separated, interchanged, and/or rearranged without departing from the technical concept of the present disclosure.

The use of cross-hatching and/or shading in the drawings is generally used to clarify the boundaries between adjacent components. As such, unless otherwise noted, the presence or absence of cross-hatching or shading does not convey or indicate any preference or requirement for a particular material, material property, size, proportion, commonality between the illustrated components and/or any other characteristic, attribute, property, etc., of a component. Further, in the drawings, the size and relative sizes of components may be exaggerated for clarity and/or descriptive purposes. While example embodiments may be practiced differently, the specific process sequence may be performed in a different order than that described. For example, two processes described consecutively may be performed substantially simultaneously or in reverse order to that described. In addition, like reference numerals denote like parts.

When an element is referred to as being "on" or "on," "connected to" or "coupled to" another element, it can be directly on, connected or coupled to the other element or intervening elements may be present. However, when an element is referred to as being "directly on," "directly connected to" or "directly coupled to" another element, there are no intervening elements present. For purposes of this disclosure, the term "connected" may refer to physically, electrically, etc., and may or may not have intermediate components.

For descriptive purposes, the present disclosure may use spatially relative terms such as "below … …," below … …, "" below … …, "" below, "" above … …, "" above, "" … …, "" higher, "and" side (e.g., as in "side wall") to describe one component's relationship to another (other) component as illustrated in the figures. Spatially relative terms are intended to encompass different orientations of the device in use, operation, and/or manufacture in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "below … …" can encompass both an orientation of "above" and "below". Further, the devices may be otherwise positioned (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, when the terms "comprises" and/or "comprising" and variations thereof are used in this specification, the presence of stated features, integers, steps, operations, elements, components and/or groups thereof are stated but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof. It is also noted that, as used herein, the terms "substantially," "about," and other similar terms are used as approximate terms and not as degree terms, and as such, are used to interpret inherent deviations in measured values, calculated values, and/or provided values that would be recognized by one of ordinary skill in the art.

According to one aspect of the present disclosure, a lithium battery pack management chip is provided.

Fig. 1 illustrates a lithium battery pack management chip 10 according to one embodiment of the present disclosure. The lithium battery pack management chip 10 is used for managing the lithium battery pack 11, and the lithium battery pack 11 comprises N lithium battery cells connected in series.

As shown in fig. 1, the lithium battery pack management chip 10 may include: the circuit comprises a multiplexing unit 110, a signal amplifying unit 120, an analog-to-digital conversion unit 130, a first filtering unit 104, a comparison conversion unit 150, a state filtering unit 160 and a switch control module 170.

The multiplexing unit 110 is controlled so as to collect the battery voltages VC 0-VCn of one of the N lithium battery cells, respectively. Wherein the multiplexing unit 110 may be gated to collect the battery voltage of each of the N lithium battery cells in a time division multiplexing manner. Among them, the gating of the multiplexing unit 110 may be controlled by the channel control unit 111.

The signal amplification unit 120 (amplifier) receives the battery voltage of one lithium battery selected from the multiplexing unit 110 and amplifies the battery voltage to generate an amplified signal, which is supplied to the analog-to-digital conversion unit 130. For example, the amplifier may be an adjustable gain amplifier, and the gain of the signal amplifying unit 120 is adjusted by the gain control unit 121. For the voltage of the single battery, the detection value ranges of the charging and discharging current and the temperature are very different, and in order to fully utilize the resolution of the ADC, before the sampling value is sent to the ADC, the sampling value is converted from analog to digital in the full-scale range of the ADC through an analog amplifier with controllable gain as far as possible.

The analog-to-digital conversion unit 130 receives the battery voltage and converts the battery voltage into a digital signal. Wherein the analog-to-digital conversion unit 130 may be a high-precision ADC.

The first filtering unit 140 is configured to perform filtering processing on the digital signal and generate a filtered signal. The first filtering unit 140 may be an FIR filter.

The comparison and conversion unit 150 is used for comparing the filtered signal with a preset voltage threshold so as to generate state information. The preset voltage threshold comprises an overvoltage threshold and an undervoltage threshold, and the filtered signal is compared with the overvoltage threshold and the undervoltage threshold respectively so as to convert the filtered signal into state information.

The state filtering unit 160 converts the state information into a voltage state signal. The voltage status signals include an over-voltage status signal and an under-voltage status signal.

The switch control module 170 generates control signals of the charge switch 12 and the discharge switch 13 of the lithium battery pack based on the voltage status signal to control the on/off of the charge switch 12 and the discharge switch 13, so as to control the charge and discharge of the lithium battery pack.

The analog front end is formed by an amplifier with adjustable gain and an ADC with high precision, the battery voltage is collected by time division multiplexing, the battery voltage converted by the ADC is filtered by the first filtering unit 140 and then is compared and converted with an overvoltage threshold and an undervoltage threshold respectively, wherein the converted data can be single-bit state information, and the single-bit state information is converted into an undervoltage state or an overvoltage state by the state filtering unit and is provided for the switch control module.

The lithium battery pack management chip 10 may further include an equalization determination module (not shown) for receiving the filtered signal output by the first filtering unit 140 to determine an equalization condition of the battery voltages of the N lithium battery cells.

Fig. 2 illustrates a lithium battery pack management chip according to one embodiment of the present disclosure.

The lithium battery pack management chip 20 is used for managing the lithium battery pack 21, and the lithium battery pack 21 comprises N lithium battery cells connected in series.

As shown in fig. 2, the lithium battery pack management chip 20 may include: the circuit comprises a multiplexing unit 210, a signal amplifying unit 220, an analog-to-digital conversion unit 230, a first filtering unit 240, a comparison conversion unit 250, a state filtering unit 260 and a switch control module 270.

The multiplexing unit 210 is controlled so as to collect the battery voltages VC 0-VCn of one of the N lithium battery cells, respectively. Wherein the multiplexing unit 210 can be gated to collect the battery voltage of each of the N lithium battery cells in a time division multiplexing manner. Among them, the gating of the multiplexing unit 210 may be controlled by the channel control unit 211.

The signal amplification unit 220 (amplifier) receives the battery voltage from one lithium battery selected by the multiplexing unit 210 and amplifies the battery voltage to generate an amplified signal, which is supplied to the analog-to-digital conversion unit 230. The amplifier may be, for example, an adjustable gain amplifier, and the gain of the signal amplifying unit 220 is adjusted by the gain control unit 221.

The analog-to-digital conversion unit 230 receives the battery voltage and converts the battery voltage into a digital signal. Wherein the analog-to-digital conversion unit 230 may be a high-precision ADC.

The first filtering unit 240 is configured to perform filtering processing on the digital signal and generate a filtered signal. The first filtering unit 240 may be an FIR filter.

The comparison and conversion unit 250 is used for comparing the filtered signal with a preset voltage threshold so as to generate state information. The preset voltage threshold comprises an overvoltage threshold and an undervoltage threshold, and the filtered signal is compared with the overvoltage threshold and the undervoltage threshold respectively so as to convert the filtered signal into state information.

The state filtering unit 260 converts the state information into a voltage state signal. The voltage status signals include an over-voltage status signal and an under-voltage status signal.

The switch control module 270 generates control signals for the charge switch 22 and the discharge switch 23 of the lithium battery pack based on the voltage status signal to control the on/off of the charge switch 22 and the discharge switch 23, so as to control the charging and discharging of the lithium battery pack.

As shown in fig. 2, the number of the first filtering units 240 is N, and each first filtering unit 240 in the N first filtering units 240 is configured to respectively perform filtering processing on a digital signal generated by the battery voltage of each lithium battery cell of the N lithium battery cells collected by the multiplexing unit. The number of the comparison and conversion units 250 is N, and each of the N comparison and conversion units is configured to receive the filtered signal output by each of the N first filtering units, respectively. The number of the state filtering units 260 is N, and each of the N state filtering units is configured to receive the state information output by each of the N comparison and conversion units, respectively.

It should be noted that, as shown in fig. 2, the number of the signal amplifying units 200 and the analog-to-digital converting units 230 is one.

According to a further example, the system further includes an equalization determination module (not shown), where the equalization determination module is configured to receive the filtered signal output by the first filtering unit, so as to determine an equalization condition of the battery voltages of the N lithium battery cells.

According to a further example, a temperature sensing unit 24, an N +1 th first filter 241, an N +1 th comparison conversion unit 251, and an N +1 th state filtering unit 261 are further included.

The temperature sensing unit 24 may be in the form of a thermistor, and is disposed near the lithium battery pack, for detecting the temperature of the lithium battery pack, and representing the temperature value by detecting the voltage across the thermistor, such that the temperature sensing unit 24 will generate a voltage signal representing the temperature value, and collect the temperature voltage value of the temperature sensing unit by controlling the multiplexing unit, and amplify the temperature voltage value by the signal amplifying unit to generate an amplified temperature voltage signal, the analog-to-digital converting unit receives the amplified temperature voltage signal and outputs it to the N +1 th first filter for filtering to generate a filtered temperature voltage signal, the N +1 th comparison converting unit is for comparing the filtered temperature voltage signal with a preset temperature threshold to generate temperature state information, the N +1 th state filtering unit converts the temperature state information into a temperature state signal, the switch control module controls the on and off of the charging switch and the discharging switch according to the temperature state signal.

The preset temperature threshold comprises a charging low-temperature threshold, a charging high-temperature threshold, a discharging low-temperature threshold and a discharging high-temperature threshold, and the filtered temperature voltage signal is respectively compared with the charging low-temperature threshold, the charging high-temperature threshold, the discharging low-temperature threshold and the discharging high-temperature threshold according to the charging and discharging state of the lithium battery pack.

The temperature state signal includes a low temperature state of charge, a high temperature state of charge, a low temperature state of discharge, and a high temperature state of discharge.

According to a further example, a current sensing unit 25, an N +2 th first filter (not shown), an N +2 th comparison conversion unit (not shown), and a state filtering group (not shown) are further included.

The current sensing unit may be a detection resistor connected in series to a current path of the lithium battery pack and configured to detect a charging and discharging current of the lithium battery pack.

The detection current of the current sensing unit is collected by controlling the multiplexing unit, the detection current is amplified by the signal amplification unit to generate an amplified first voltage signal, the analog-to-digital conversion unit receives the amplified first voltage signal and outputs the amplified first voltage signal to the (N + 2) th first filter for filtering to generate a filtered first voltage signal, the (N + 2) th comparison and conversion unit is used for comparing the filtered first voltage signal with a preset current-voltage threshold value to generate current state information, the state filtering group converts the current state information into a current state signal, and the switch control module controls the on and off of the charging switch and the discharging switch according to the current state signal.

The state filtering group comprises a plurality of state filters, and the state filters correspond to different current thresholds and response times, so that the response time is shorter as the charging and discharging current is larger.

The state filtering unit comprises a state register and a counter, when the state information received by the state filtering unit is opposite to the state information registered by the state register, the counter is increased by 1, otherwise, the counter is cleared, and when the counter is accumulated to a specified response time threshold value, the state register is turned over. In the present disclosure, fig. 7 shows a schematic diagram of a filtering unit according to a state.

In a further example of the present disclosure, the N +2 th first filter in the above example may not be included therein. The current sensing unit may be a detection resistor connected in series to a current path of the lithium battery pack and configured to detect a charge and discharge current of the lithium battery pack to generate a voltage signal representing the charge and discharge current. The voltage signal of the current sensing unit is collected by controlling the multiplexing unit, the voltage signal is amplified by the signal amplifying unit to generate an amplified first voltage signal (the voltage signal is smaller than a voltage value of a battery), the analog-to-digital conversion unit receives the amplified first voltage signal and outputs the amplified first voltage signal to the (N + 2) th comparison and conversion unit, the (N + 2) th comparison and conversion unit is used for comparing the filtered first voltage signal with a preset current-voltage threshold value to generate current state information, the state filtering group converts the current state information into the current state signal, and the switch control module controls the conduction and the disconnection of the charging switch and the discharging switch according to the current state signal.

Fig. 3 illustrates a lithium battery pack management chip according to one embodiment of the present disclosure.

The lithium battery pack management chip 30 is used for managing the lithium battery pack 31, and the lithium battery pack 31 includes N lithium battery cells connected in series.

As shown in fig. 3, the lithium battery pack management chip 30 may include: the circuit comprises a multiplexing unit 310, a signal amplifying unit 320, an analog-to-digital conversion unit 330, a first filtering unit 340, a comparison conversion unit 350, a state filtering unit 360 and a switch control module 370.

The multiplexing unit 310 is controlled so as to collect the battery voltages VC 0-VCn of one of the N lithium battery cells, respectively. Wherein the multiplexing unit 310 may be gated to collect the battery voltage of each of the N lithium battery cells in a time division multiplexing manner. The gating of the multiplexing unit 310 may be controlled by the channel control unit 311.

The signal amplification unit 320 (amplifier) receives the battery voltage of one lithium battery selected by the multiplexing unit 310 and amplifies the battery voltage to generate an amplified signal, which is supplied to the analog-to-digital conversion unit 330. The amplifier may be, for example, an adjustable gain amplifier, and the gain of the signal amplifying unit 320 is adjusted by the gain control unit 321.

The analog-to-digital conversion unit 330 receives the battery voltage and converts the battery voltage into a digital signal. Wherein the analog-to-digital conversion unit 330 may be a high-precision ADC.

The first filtering unit 340 is configured to perform filtering processing on the digital signal and generate a filtered signal. The first filtering unit 340 may be an FIR filter.

The comparison and conversion unit 350 (digital comparator 2) is used for comparing the filtered signal with a preset voltage threshold value so as to generate state information. The preset voltage threshold comprises an overvoltage threshold and an undervoltage threshold, and the filtered signal is compared with the overvoltage threshold and the undervoltage threshold respectively so as to convert the filtered signal into state information. The state information is single-bit state information.

The state filtering unit 360 converts the state information into a voltage state signal. The voltage status signals include an over-voltage status signal and an under-voltage status signal.

The switch control module 370 generates control signals of the charge switch 32 and the discharge switch 33 of the lithium battery pack based on the voltage status signal to control the on/off of the charge switch 22 and the discharge switch 33, thereby controlling the charge and discharge of the lithium battery pack.

According to an example, a gain control module 321 is further included, and the gain control module 321 is configured to adjust an amplification gain factor of the signal amplification unit.

According to an example, the system further comprises an equalization judging module 380, a first median filter 341 and a kalman filter 351, wherein the first median filter 341 receives the digital signal from the analog-to-digital conversion unit and performs median filtering, the processed signal is provided to the kalman filter 351 for processing, the signal processed by the kalman filter 351 is provided to the equalization judging module, and the equalization judging module 380 judges the equalization condition of the battery voltage of the N lithium battery cells according to the received signal.

The output signal of the equalization discrimination module 380 is used to control the MOSFETs 390 connected in parallel with each battery cell, for example, the drain and source of each MOSFET are respectively connected to two ends of each battery cell, and the output signal controls the gate of the MOSFET.

According to an example, the current sensing unit 35, the second comparison and conversion unit 352, and the state filtering group 361 are further included. The current sensing unit is used for detecting the charging and discharging current of the lithium battery pack to generate a voltage signal representing the charging and discharging current, the voltage signal of the current sensing unit is collected by controlling the multiplexing unit, the voltage signal is amplified by the signal amplifying unit to generate an amplified first voltage signal, the analog-to-digital conversion unit receives the amplified first voltage signal and outputs the amplified first voltage signal to the second comparison and conversion unit, the second comparison and conversion unit is used for comparing the filtered first voltage signal with a preset current-voltage threshold value to generate current state information, the state filtering group converts the current state information into the current state signal, and the switch control module controls the charging switch and the discharging switch to be switched on and off according to the current state signal.

According to an example, the lithium battery pack temperature detection device further comprises a temperature sensing unit 34, a second median filter 342, a third comparison and conversion unit 353, and a second state filtering unit 362, wherein the temperature sensing unit is used for detecting the temperature of the lithium battery pack, the detection temperature of the temperature sensing unit is collected by controlling the multiplexing unit, the detection temperature is amplified by the signal amplifying unit to generate an amplified temperature voltage signal, the analog-to-digital conversion unit receives the amplified temperature voltage signal and outputs the amplified temperature voltage signal to the second median filter for filtering to generate a filtered temperature voltage signal, the third comparison and conversion unit is used for comparing the filtered temperature voltage signal with a preset temperature threshold value, the second state filtering unit converts the temperature state information into a temperature state signal, and the switch control module controls the charging switch and the discharging switch to be switched on and off according to the temperature state signal. The preset temperature threshold comprises a charging low-temperature threshold, a charging high-temperature threshold, a discharging low-temperature threshold and a discharging high-temperature threshold, and the filtered temperature voltage signal is respectively compared with the charging low-temperature threshold, the charging high-temperature threshold, the discharging low-temperature threshold and the discharging high-temperature threshold according to the charging and discharging state of the lithium battery pack. The temperature state signal includes a low temperature state of charge, a high temperature state of charge, a low temperature state of discharge, and a high temperature state of discharge.

According to an example, the open circuit detection unit 391 further includes a battery open circuit detection unit, where the battery open circuit detection unit includes N capacitors, each capacitor in the N capacitors is connected in parallel with each lithium battery cell in the N lithium battery cells, and charges each capacitor after discharging, obtains a battery voltage of each lithium battery cell by measuring a voltage across each capacitor, and performs open circuit detection according to the battery voltage. If an open circuit detection occurs, the measured cell voltage may be greater than the cell maximum voltage or less than the cell minimum voltage.

In another example of the present disclosure, the battery pack further includes a current analog-to-digital conversion unit, a current sensing unit, a second comparison conversion unit, and a state filtering set, the current sensing unit is configured to detect a charge and discharge current of the lithium battery pack to generate a voltage signal representing the charge and discharge current, the voltage Ifairy of the current sensing unit is collected by controlling the multiplexing unit, the signal amplification unit is used for amplifying the voltage Ifairy to generate an amplified first voltage signal, the current analog-to-digital conversion unit is used for receiving the amplified first voltage signal and outputting the amplified first voltage signal to the second comparison and conversion unit, the second comparison and conversion unit is used for comparing the filtered first voltage signal with a preset current-to-voltage threshold value, the state filtering group converts the current state information into a current state signal, and the switch control module controls the charging switch and the discharging switch to be switched on and off according to the current state signal. If an ADC is to detect both voltage and current, the sampling period of the ADC cannot be too long, which would result in loss of current information, and if it is too short, which would result in significant power consumption. In this example, the current is detected by adding a separate ADC, which may cause the power consumption of the ADC to decrease, and the ADC for detecting the current is activated only because it operates only occasionally, for example, when the current value is greater than a predetermined value or is controlled digitally intermittently, and the average power consumption may be controlled by controlling the duty ratio. Power consumption can be effectively reduced according to this approach.

In another example of the present disclosure, the lithium battery pack further includes a current sensing unit, an overcurrent comparator, a second comparison and conversion unit, and a state filtering group, the current sensing unit is configured to detect a charging and discharging current of the lithium battery pack to generate a voltage signal representing the charging and discharging current, collect a voltage signal of the current sensing unit by controlling the multiplexing unit, amplify the voltage signal by the signal amplifying unit to generate an amplified first voltage signal, the analog-to-digital conversion unit receives the amplified first voltage signal and outputs the amplified first voltage signal to the second comparison and conversion unit, the second comparison and conversion unit is configured to compare the filtered first voltage signal with a preset current-to-voltage threshold value to generate current state information, the state filtering group converts the current state information into a current state signal, and the switch control module controls the charging switch and the discharging switch to be turned on or off according to the current state signal, the overcurrent comparator is used for comparing the charging and discharging current detected by the current sensing unit with a preset current-voltage threshold value to judge whether the charging and discharging current is larger than the preset current-voltage threshold value, and if so, the analog-to-digital conversion unit is controlled to shorten the sampling period of the analog-to-digital conversion unit.

According to the example, by adding the overcurrent comparator, when the voltage signal corresponding to the detected current is greater than the threshold value, the sampling speed of the ADC can be increased, so that real-time detection of the voltage and the current can be realized by using one ADC.

According to another aspect of the present disclosure, there is provided a lithium battery pack management method, the lithium battery pack including N lithium battery cells connected in series. For the related content in the lithium battery pack management method, reference may be made to the above description, and for the sake of brevity, the description is not repeated herein.

Fig. 4 illustrates a lithium battery pack management method 400 according to one example of the present disclosure. As shown in fig. 4, the method may include the following steps.

In step 402, the multiplexing unit is controlled to collect the battery voltage of one of the N lithium battery cells, respectively.

In step 404, the battery voltage is received by the analog-to-digital conversion unit and converted into a digital signal.

In step 406, the first filtering unit is used to filter the digital signal and generate a filtered signal.

In step 408, the comparison and conversion unit is used to compare the filtered signal with a preset voltage threshold so as to generate status information.

In step 410, the state information is converted into a voltage state signal by a state filtering unit.

In step 412, the switch control module generates control signals for the charge switch and the discharge switch of the lithium battery pack based on the voltage status signal to control the on/off of the charge switch and the discharge switch, thereby controlling the charge and discharge of the lithium battery pack.

Further, the lithium battery pack management method 400 may further include receiving, by the signal amplification unit, a battery voltage of one lithium battery from the multiplexing unit, and amplifying the battery voltage to generate an amplified signal, which is provided to the analog-to-digital conversion unit, for example, as shown in step 403.

Furthermore, the first filtering units are FIR filters and are N in number, and each of the N first filtering units is configured to perform filtering processing on the digital signal generated by the battery voltage of each of the N lithium battery cells collected by the multiplexing unit.

Furthermore, the number of the comparison and conversion units is N, and each of the N comparison and conversion units is configured to receive the filtered signal output by each of the N first filtering units, respectively.

Furthermore, the number of the state filtering units is N, and each of the N state filtering units is configured to receive the state information output by each of the N comparison and conversion units, respectively.

Further, the preset voltage threshold includes an overvoltage threshold and an undervoltage threshold, and the filtered signal is compared with the overvoltage threshold and the undervoltage threshold, respectively, so as to convert the filtered signal into the state information.

Further, the status information is single-bit status information.

Further, the voltage status signal includes an over-voltage status signal and an under-voltage status signal.

Further, the method also comprises the step of adjusting the amplification gain factor of the signal amplification unit.

Furthermore, the number of the signal amplifying units and the analog-to-digital conversion units is one.

Furthermore, the method is characterized by also comprising the step of receiving the filtered signals output by the first filtering unit so as to judge the balance condition of the battery voltages of the N lithium battery cells.

Further, as shown in fig. 5, the detection of the temperature is also included. Wherein the temperature detection method may include the following.

In step 502, the temperature sensing unit is used to detect the temperature of the lithium battery pack.

In step 504, the detected temperature of the temperature sensing unit is collected by controlling the multiplexing unit.

In step 506, the detected temperature is amplified by the signal amplifying unit to generate an amplified temperature voltage signal.

In step 508, the analog-to-digital conversion unit receives the amplified temperature voltage signal and performs analog-to-digital conversion.

In step 510, the (N + 1) th first filter performs filtering to generate a filtered temperature voltage signal.

In step 512, the (N + 1) th comparing and converting unit is configured to compare the filtered temperature voltage signal with a preset temperature threshold, so as to generate temperature status information.

In step 514, the (N + 1) th state filtering unit converts the temperature state information into a temperature state signal.

In step 516, the switch control module controls the charging switch and the discharging switch to be turned on or off according to the temperature status signal.

The (N + 1) th state filtering unit converts the temperature state information into a temperature state signal, and the switch control module controls the on and off of the charging switch and the discharging switch according to the temperature state signal.

Further, the preset temperature threshold comprises a charging low-temperature threshold, a charging high-temperature threshold, a discharging low-temperature threshold and a discharging high-temperature threshold, and the filtered temperature voltage signal is respectively compared with the charging low-temperature threshold, the charging high-temperature threshold, the discharging low-temperature threshold and the discharging high-temperature threshold according to the charging and discharging state of the lithium battery pack.

Further, the temperature state signal includes a charge low temperature state, a charge high temperature state, a discharge low temperature state, and a discharge high temperature state.

Further, a current detection method is also provided, and as shown in fig. 6, the current detection method may include the following.

In step 602, the current sensing unit is used for detecting a charge/discharge current of the lithium battery pack to generate a voltage signal representing the charge/discharge current.

In step 604, the voltage signal of the current sensing unit is collected by controlling the multiplexing unit.

In step 606, the voltage signal is amplified by the signal amplifying unit to generate an amplified first voltage signal.

In step 608, the analog-to-digital conversion unit receives the amplified first voltage signal and performs analog-to-digital conversion.

In step 610, the (N + 1) th first filter filters to generate a filtered first voltage signal.

In step 612, the (N + 1) th comparing and converting unit is configured to compare the filtered first voltage signal with a preset current-voltage threshold, so as to generate current status information.

In step 614, the state filter bank converts the current state information to a current state signal.

In step 616, the switch control module controls the charging switch and the discharging switch to be turned on or off according to the current status signal.

Further, the state filter group comprises a plurality of state filters, and the state filters correspond to different current thresholds and response times, so that the response time is shorter as the charging and discharging current is larger.

Further, the state filtering unit comprises a state register and a counter, when the state information received by the state filtering unit is opposite to the state information registered by the state register, the counter is increased by 1, otherwise, the counter is cleared, and when the counter is accumulated to a specified response time threshold value, the state register is turned over.

In a further example of the present disclosure, the first filtering unit is a FIR filter.

The preset voltage threshold comprises an overvoltage threshold and an undervoltage threshold, and the filtered signal is compared with the overvoltage threshold and the undervoltage threshold respectively so as to convert the filtered signal into state information. The state information is single-bit state information.

The voltage status signals include an over-voltage status signal and an under-voltage status signal.

The gain control module is used for adjusting the amplification gain coefficient of the signal amplification unit.

The balancing judgment module is used for judging the balancing condition of the battery voltages of the N lithium battery monomers according to the received signals.

In one example, the lithium battery pack further comprises a current sensing unit, a second comparison and conversion unit and a state filtering group, wherein the current sensing unit is used for detecting charging and discharging currents of the lithium battery pack, the detection currents of the current sensing unit are collected by controlling the multiplexing unit, the detection currents are amplified by the signal amplification unit to generate amplified first voltage signals, the analog-to-digital conversion unit receives the amplified first voltage signals and outputs the amplified first voltage signals to the second comparison and conversion unit, the second comparison and conversion unit is used for comparing the filtered first voltage signals with a preset current voltage threshold value to generate current state information, the state filtering group converts the current state information into current state signals, and the switch control module controls the charging switch and the discharging switch to be switched on and off according to the current state signals.

In one example, the lithium ion battery pack temperature detection device further comprises a temperature sensing unit, a second median filter, a third comparison and conversion unit and a second state filtering unit, wherein the temperature sensing unit is used for detecting the temperature of the lithium ion battery pack, the detection temperature of the temperature sensing unit is collected by controlling the multiplexing unit, the detection temperature is amplified by the signal amplifying unit to generate an amplified temperature voltage signal, the analog-to-digital conversion unit receives the amplified temperature voltage signal and outputs the amplified temperature voltage signal to the second median filter for filtering to generate a filtered temperature voltage signal, the third comparison and conversion unit is used for comparing the filtered temperature voltage signal with a preset temperature threshold value, the second state filtering unit converts the temperature state information into a temperature state signal, and the switch control module controls the charging switch and the discharging switch to be switched on and off according to the temperature state signal.

In one example, the open circuit detection device further comprises a battery open circuit detection unit, wherein the battery open circuit detection unit comprises N capacitors, each capacitor in the N capacitors is connected in parallel with each lithium battery cell in the N lithium battery cells respectively, each capacitor is charged after being discharged, the battery voltage of each lithium battery cell is obtained by measuring the voltage at two ends of each capacitor, and open circuit detection is performed according to the battery voltage.

In one example, the device further comprises a current analog-to-digital conversion unit, a current sensing unit, a second comparison conversion unit and a state filtering set, wherein the current sensing unit is used for detecting the charge and discharge current of the lithium battery set to generate a voltage signal representing the charge and discharge current, the multiplexing unit is controlled to collect voltage signals of the current sensing unit, the signal amplification unit amplifies the voltage signals to generate amplified first voltage signals, the current analog-to-digital conversion unit receives the amplified first voltage signals and outputs the amplified first voltage signals to the second comparison and conversion unit, the second comparison and conversion unit is used for comparing the filtered first voltage signals with a preset current-voltage threshold value, the state filtering group converts the current state information into a current state signal, and the switch control module controls the charging switch and the discharging switch to be switched on and off according to the current state signal.

In one example, the lithium battery pack further comprises a current sensing unit, an overcurrent comparator, a second comparison and conversion unit and a state filtering set, wherein the current sensing unit is used for detecting the charging and discharging current of the lithium battery pack to generate a voltage signal representing the charging and discharging current, the multiplexing unit is controlled to collect the voltage signal of the current sensing unit, the signal amplifying unit is used for amplifying the voltage signal to generate an amplified first voltage signal, the analog-to-digital conversion unit is used for receiving the amplified first voltage signal and outputting the amplified first voltage signal to the second comparison and conversion unit, the second comparison and conversion unit is used for comparing the filtered first voltage signal with a preset current voltage threshold value to generate current state information, the state filtering set is used for converting the current state information into a current state signal, and the switch control module is used for controlling the charging switch and the discharging switch to be switched on and off according to the current state signal, the overcurrent comparator is used for comparing the charging and discharging current detected by the current sensing unit with a preset current-voltage threshold value to judge whether the charging and discharging current is larger than the preset current-voltage threshold value, and if so, the analog-to-digital conversion unit is controlled to shorten the sampling period of the analog-to-digital conversion unit.

According to a further embodiment of the present disclosure, there is also provided a lithium battery pack management system including: the lithium battery pack management chip is at least used for detecting the battery voltage of each lithium battery cell in the N lithium battery cells of the lithium battery pack; and the lithium battery pack management chip controls the on and off of the charging switch and the discharging switch according to the detected battery voltage.

In a lithium battery management system, the priority of detection of charge and discharge current is highest, and the sampling frequency is also required to be as high as possible. The present disclosure designs an analog front end channel control method to allocate various detected time gaps. During working, the sampling frequency of the sampling circuit working at the charging and discharging current is unchanged, a plurality of sampling periods are allocated to voltage detection or temperature detection according to the sampling frequency requirements of voltage and temperature, and any two voltage detection or temperature detection periods are not adjacent. In a non-current detection period, the current value is predicted according to the latest current sampling values and the change rate, and because the time interval of two times of voltage or temperature detection is long enough, the system can be considered to continuously detect the charging and discharging current all the time, so that the current, voltage and temperature detection is realized by using a set of analog front end.

In the median filter of the present disclosure, recursive median filtering may be adopted, on the premise that the sampling rate is not reduced, a fifo queue of a predetermined length is set, a new value is sampled every period, the tail of the sampled queue is inserted and the old value at the head of the queue is removed, the queue is sorted, and the intermediate value is taken as the final result.

According to a further embodiment of the present disclosure, there is also provided an electrical device including: a lithium battery pack; in the lithium battery pack management system, the lithium battery pack management system is used for controlling the charging and discharging of the lithium battery pack; and the electric device is connected with the lithium battery pack so as to supply power through the lithium battery pack.

In the description herein, reference to the description of the terms "one embodiment/mode," "some embodiments/modes," "example," "specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment/mode or example is included in at least one embodiment/mode or example of the application. In this specification, the schematic representations of the terms used above are not necessarily intended to be the same embodiment/mode or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments/modes or examples. Furthermore, the various embodiments/aspects or examples and features of the various embodiments/aspects or examples described in this specification can be combined and combined by one skilled in the art without conflicting therewith.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

It will be understood by those skilled in the art that the foregoing embodiments are merely for clarity of illustration of the disclosure and are not intended to limit the scope of the disclosure. Other variations or modifications may occur to those skilled in the art, based on the foregoing disclosure, and are still within the scope of the present disclosure.

Claims

1. A lithium battery pack management chip comprises N lithium battery cells connected in series, and is characterized by comprising:

2. The lithium battery pack management chip according to claim 1, further comprising a signal amplification unit, wherein the signal amplification unit receives a battery voltage of one lithium battery from the multiplexing unit and amplifies the battery voltage to generate an amplified signal, and the amplified signal is provided to the analog-to-digital conversion unit;

optionally, the first filtering units are FIR filters and are N in number, and each of the N first filtering units is configured to respectively perform filtering processing on a digital signal generated by the battery voltage of each of the N lithium battery cells collected by the multiplexing unit;

optionally, the number of the comparison and conversion units is N, and each of the N comparison and conversion units is configured to receive the filtered signal output by each of the N first filtering units, respectively.

3. The lithium battery pack management chip according to claim 1, wherein the number of the state filtering units is N, and each of the N state filtering units is configured to receive the state information output by each of the N comparison and conversion units;

optionally, the preset voltage threshold includes an overvoltage threshold and an undervoltage threshold, and the filtered signal is compared with the overvoltage threshold and the undervoltage threshold, respectively, so as to convert the filtered signal into state information;

optionally, the status information is single-bit status information;

optionally, the voltage status signal includes an overvoltage status signal and an undervoltage status signal;

optionally, the apparatus further includes a gain control module, where the gain control module is configured to adjust an amplification gain coefficient of the signal amplification unit;

optionally, the number of the signal amplifying units and the number of the analog-to-digital conversion units are one;

optionally, the system further comprises an equalization judging module, wherein the equalization judging module is configured to receive the filtered signal output by the first filtering unit, so as to judge the equalization condition of the battery voltages of the N lithium battery cells.

4. The lithium battery pack management chip according to any one of claims 1 to 3, further comprising a temperature sensing unit, an N +1 th first filter, an N +1 th comparison and conversion unit, and an N +1 th status filtering unit, wherein the temperature sensing unit is configured to detect a temperature of the lithium battery pack to generate a temperature voltage value, collect the temperature voltage value of the temperature sensing unit by controlling the multiplexing unit, and amplify the temperature voltage value by the signal amplifying unit to generate an amplified temperature voltage signal, the analog-to-digital conversion unit receives the amplified temperature voltage signal and outputs the amplified temperature voltage signal to the N +1 th first filter for filtering to generate a filtered temperature voltage signal, and the N +1 th comparison and conversion unit is configured to compare the filtered temperature voltage signal with a preset temperature threshold, the (N + 1) th state filtering unit converts the temperature state information into a temperature state signal, and the switch control module controls the on and off of the charging switch and the discharging switch according to the temperature state signal;

optionally, the preset temperature threshold includes a charging low temperature threshold, a charging high temperature threshold, a discharging low temperature threshold and a discharging high temperature threshold, and the filtered temperature voltage signal is respectively compared with the charging low temperature threshold, the charging high temperature threshold, the discharging low temperature threshold and the discharging high temperature threshold according to the charging and discharging state of the lithium battery pack;

optionally, the temperature status signal includes a low temperature state of charge, a high temperature state of charge, a low temperature state of discharge, and a high temperature state of discharge.

5. The lithium battery pack management chip according to any one of claims 1 to 4, further comprising a current sensing unit, an N +1 th first filter, an N +1 th comparison and conversion unit, and a state filtering set, wherein the current sensing unit is configured to detect a charging and discharging current of the lithium battery pack to generate a first voltage value representing the charging and discharging current, and collect a first voltage value of the current sensing unit by controlling the multiplexing unit, and amplify the first voltage value by the signal amplifying unit to generate an amplified first voltage signal, the analog-to-digital conversion unit receives the amplified first voltage signal and outputs the amplified first voltage signal to the N +1 th first filter for filtering to generate a filtered first voltage signal, and the N +1 th comparison and conversion unit is configured to compare the filtered first voltage signal with a preset current voltage threshold, the state filtering group converts the current state information into a current state signal, and the switch control module controls the on and off of the charging switch and the discharging switch according to the current state signal.

6. The lithium battery pack management chip according to claim 1, wherein the state filter set comprises a plurality of state filters corresponding to different current thresholds and response times, such that the greater the charge and discharge current, the shorter the response time;

optionally, the state filtering unit includes a state register and a counter, when the state information received by the state filtering unit is opposite to the state information registered by the state register, the counter is incremented by 1, otherwise, the counter is cleared, and when the counter is incremented to a specified response time threshold, the state register is turned over;

optionally, the first filtering unit is an FIR filter;

optionally, the status information is single-bit status information;

optionally, the system further includes an equalization determination module, a first median filter, and a kalman filter, where the first median filter receives the digital signal from the analog-to-digital conversion unit, performs median filtering, the processed signal is provided to the kalman filter for processing, the signal processed by the kalman filter is provided to the equalization determination module, and the equalization determination module determines the equalization condition of the battery voltages of the N lithium battery cells according to the received signal.

7. The lithium battery pack management chip according to any one of claims 1 to 6, further comprising a current sensing unit, a second comparison and conversion unit, and a state filtering set, wherein the current sensing unit is configured to detect a charging and discharging current of the lithium battery pack to generate a first voltage value representing the charging and discharging current, collect the first voltage value of the current sensing unit by controlling the multiplexing unit, and amplify the first voltage value by the signal amplifying unit to generate an amplified first voltage signal, the analog-to-digital conversion unit receives the amplified first voltage signal and outputs the amplified first voltage signal to the second comparison and conversion unit, the second comparison and conversion unit is configured to compare the filtered first voltage signal with a preset current-to-voltage threshold to generate a current state information, and the state filtering set converts the current state information into a current state signal, the switch control module controls the on and off of the charging switch and the discharging switch according to the current state signal;

optionally, the temperature sensing unit is configured to detect a temperature of the lithium battery pack to generate a temperature voltage value, acquire the temperature voltage value of the temperature sensing unit by controlling the multiplexing unit, amplify the temperature voltage value by the signal amplifying unit to generate an amplified temperature voltage signal, receive the amplified temperature voltage signal by the analog-to-digital conversion unit and output the amplified temperature voltage signal to the second median filter to filter the amplified temperature voltage signal to generate a filtered detected temperature signal, compare the filtered temperature voltage signal with a preset temperature threshold to generate temperature state information, and convert the temperature state information into a temperature state signal by the second state filtering unit, the switch control module controls the on and off of the charging switch and the discharging switch according to the temperature state signal;

optionally, the temperature status signal includes a charge low temperature status, a charge high temperature status, a discharge low temperature status, and a discharge high temperature status;

optionally, the battery open circuit detection unit further includes N capacitors, each capacitor in the N capacitors is connected in parallel with each lithium battery cell in the N lithium battery cells, each capacitor is charged after being discharged, the battery voltage of each lithium battery cell is obtained by measuring the voltage at two ends of each capacitor, and the open circuit detection is performed according to the battery voltage.

8. The lithium battery pack management chip according to any one of claims 1 to 7, further comprising a current analog-to-digital conversion unit, a current sensing unit, a second comparison and conversion unit, and a state filtering set, wherein the current sensing unit is configured to detect a charging and discharging current of the lithium battery pack to generate a first voltage value representing the charging and discharging current, collect a first voltage value of the current sensing unit by controlling the multiplexing unit, and amplify the first voltage value by the signal amplifying unit to generate an amplified first voltage signal, the current analog-to-digital conversion unit receives the amplified first voltage signal and outputs the amplified first voltage signal to the second comparison and conversion unit, and the second comparison and conversion unit is configured to compare the filtered first voltage signal with a preset current voltage threshold value to generate current state information, the state filtering group converts the current state information into a current state signal, and the switch control module controls the on and off of the charging switch and the discharging switch according to the current state signal;

optionally, the apparatus further includes a current sensing unit, an overcurrent comparator, a second comparison and conversion unit, and a state filtering set, the current sensing unit is configured to detect a charge and discharge current of the lithium battery pack to generate a first voltage value representing the charge and discharge current, and collect a first voltage value of the current sensing unit by controlling the multiplexing unit, and amplify the first voltage value by the signal amplifying unit to generate an amplified first voltage signal, the analog-to-digital conversion unit receives the amplified first voltage signal and outputs the amplified first voltage signal to the second comparison and conversion unit, the second comparison and conversion unit is configured to compare the filtered first voltage signal with a preset current-to-voltage threshold value to generate current state information, and the state filtering set converts the current state information into a current state signal, the switch control module controls the charging switch and the discharging switch to be switched on and off according to the current state signal, wherein the overcurrent comparator is used for comparing the charging and discharging current detected by the current sensing unit with a preset current voltage threshold value to judge whether the charging and discharging current is greater than the preset current voltage threshold value, and if the charging and discharging current is greater than the preset current voltage threshold value, the analog-to-digital conversion unit is controlled to shorten the sampling period of the analog-to-digital conversion unit.

9. A management method of a lithium battery pack, wherein the lithium battery pack comprises N lithium battery cells connected in series, and the management method is characterized by comprising the following steps:

10. A lithium battery pack management system, comprising:

the lithium battery pack management chip according to any one of claims 1 to 8, the lithium battery pack management chip being configured to detect at least a cell voltage of each of the N lithium battery cells of the lithium battery pack; and