CN112838623A

CN112838623A - Lithium ion battery charging method and device

Info

Publication number: CN112838623A
Application number: CN201911155631.XA
Authority: CN
Inventors: 张炳雁; 薛原; 洪达; 徐凡; 谢封超
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-11-22
Filing date: 2019-11-22
Publication date: 2021-05-25

Abstract

The application is applicable to the technical field of battery charging, and provides a lithium ion battery charging method, which comprises the following steps: firstly, charging the lithium ion battery with the rated charging voltage of the lithium ion battery until the charging current of the lithium ion battery reaches the cut-off charging current; then, charging the lithium ion battery by using the cut-off charging current until the charging voltage of the lithium ion battery reaches the cut-off charging voltage; the cut-off charging voltage is greater than the rated charging voltage of the lithium ion battery; the charging of the lithium ion battery can be finished, the step of constant voltage charging by cut-off charging voltage is reduced, so that the quick charging performance of the lithium ion battery is realized, the high-voltage on-position time of the lithium ion battery is saved, the side reaction of the anode of the lithium ion battery and the interface of electrolyte can be effectively slowed down, the aging of the battery is slowed down, and the service life of the battery is prolonged.

Description

Lithium ion battery charging method and device

Technical Field

The application belongs to the technical field of battery charging, and particularly relates to a lithium ion battery charging method and device.

Background

At present, two methods are mainly used for improving the charging speed of the lithium ion battery, wherein the first method is to improve the initial charging multiplying power, and the second method is to improve the cut-off charging voltage, and the two methods both have important influence on the service life of the lithium ion battery, so that the relationship between the charging method and the service life of the battery needs to be sufficiently coordinated.

Disclosure of Invention

The embodiment of the application provides a charging method and a charging device for a lithium ion battery, which can prolong the service life of the lithium ion battery.

In a first aspect, an embodiment of the present application provides a method for charging a lithium ion battery, including:

charging the lithium ion battery with the rated charging voltage of the lithium ion battery until the charging current of the lithium ion battery reaches the cut-off charging current;

charging the lithium ion battery with the cut-off charging current until the charging voltage of the lithium ion battery reaches a cut-off charging voltage; wherein the cut-off charging voltage is greater than the rated charging voltage of the lithium ion battery.

In one possible implementation form of the first aspect, the charging is constant voltage charging or constant current charging.

Exemplarily, the lithium ion battery is charged at a rated charging voltage of the lithium ion battery to a cut-off charging current at a constant voltage; and then carrying out constant current charging on the lithium ion battery to a cut-off charging voltage by using a cut-off charging current.

It will be appreciated that the above-described constant voltage charging or constant current charging is only an alternative embodiment, and that one possible implementation of the first aspect includes a step-regulated charging voltage mode, a step-regulated charging current mode, a constant voltage charging and a constant current charging.

In a second aspect, an embodiment of the present application provides a charging apparatus for a lithium ion battery, including:

the voltage charging module is used for charging the lithium ion battery with the rated charging voltage of the lithium ion battery until the charging current of the lithium ion battery reaches the cut-off charging current;

the current charging module is used for charging the lithium ion battery with the cut-off charging current until the charging voltage of the lithium ion battery reaches the cut-off charging voltage; wherein the cut-off charging voltage is greater than the rated charging voltage of the lithium ion battery.

In a third aspect, an embodiment of the present application provides a terminal device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor implements the lithium ion battery charging method according to any one of the first aspect when executing the computer program.

In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, where a computer program is stored, and when the computer program is executed by a processor, the method for charging a lithium ion battery according to any one of the above first aspects is implemented.

In a fifth aspect, an embodiment of the present application provides a computer program product, which, when run on a terminal device, causes the terminal device to execute the lithium ion battery charging method described in any one of the above first aspects.

It is understood that the beneficial effects of the second aspect to the fifth aspect can be referred to the related description of the first aspect, and are not described herein again.

The embodiment of the application charges the lithium ion battery to the charging current of the lithium ion battery by the rated charging voltage of the lithium ion battery to reach the cut-off charging current, and then charges the lithium ion battery to the charging voltage of the lithium ion battery by the cut-off charging current to reach the cut-off charging voltage, so that the charging of the lithium ion battery can be completed, the step of constant-voltage charging by the cut-off charging voltage is reduced, thereby realizing the quick charging performance of the lithium ion battery, simultaneously saving the high-voltage on-site time of the lithium ion battery, effectively slowing down the side reaction of the anode of the lithium ion battery and the interface of electrolyte, slowing down the aging of the battery, and prolonging the service life of.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a schematic structural diagram of a mobile phone to which a lithium ion battery charging method provided in an embodiment of the present application is applied;

fig. 2 is a schematic diagram of a software architecture for a charging method of a lithium ion battery according to an embodiment of the present disclosure;

FIG. 3 is a schematic flow diagram of a conventional lithium-ion battery charging method;

FIG. 4 is a schematic diagram showing the charging voltage and charging rate variation in the charging process of a conventional lithium ion battery charging method;

fig. 5 is a schematic flow chart of a charging method for a lithium ion battery according to an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of the current-voltage relationship during charging in a stepwise regulated charging voltage mode;

FIG. 7 is a schematic diagram of the voltage-current relationship during charging in a stepwise regulated charging current mode;

FIG. 8 is a graph comparing the charging voltage and charging time variation with the charging voltage and charging time variation of the prior art according to an embodiment of the present application

Fig. 9 is a schematic flow chart of a charging method for a lithium ion battery according to another embodiment of the present disclosure;

fig. 10 is a schematic flow chart of a charging method for a lithium ion battery according to another embodiment of the present disclosure;

fig. 11 is an exemplary diagram of a comparison result of measured charging data corresponding to a first example of the present application;

fig. 12 is an exemplary graph of measured charging data comparison results according to a second example of the present application;

fig. 13 is an exemplary diagram of a comparison result of measured charging data corresponding to the third example of the present application;

fig. 14 is a schematic structural diagram of a charging device of a lithium ion battery provided in an embodiment of the present application;

fig. 15 is a schematic structural diagram of another charging device for a lithium ion battery provided in an embodiment of the present application;

fig. 16 is a schematic structural diagram of another charging device for a lithium ion battery provided in an embodiment of the present application;

fig. 17 is a schematic structural diagram of a charging parameter testing module of a lithium ion battery charging apparatus according to an embodiment of the present disclosure;

fig. 18 is a schematic structural diagram of a charging parameter testing module of a lithium ion battery charging apparatus according to an embodiment of the present disclosure;

fig. 19 is a schematic structural diagram of a terminal device according to an embodiment of the present application.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It should also be understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

As used in this specification and the appended claims, the term "if" may be interpreted contextually as "when", "upon" or "in response to" determining "or" in response to detecting ". Similarly, the phrase "if it is determined" or "if a [ described condition or event ] is detected" may be interpreted contextually to mean "upon determining" or "in response to determining" or "upon detecting [ described condition or event ]" or "in response to detecting [ described condition or event ]".

Furthermore, in the description of the present application and the appended claims, the terms "first," "second," "third," and the like are used for distinguishing between descriptions and not necessarily for describing or implying relative importance.

Reference throughout this specification to "one embodiment" or "some embodiments," or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," or the like, in various places throughout this specification are not necessarily all referring to the same embodiment, but rather "one or more but not all embodiments" unless specifically stated otherwise. The terms "comprising," "including," "having," and variations thereof mean "including, but not limited to," unless expressly specified otherwise.

The lithium ion battery charging method provided by the embodiment of the application can be applied to mobile phones, tablet computers, wearable devices, vehicle-mounted devices, Augmented Reality (AR)/Virtual Reality (VR) devices, notebook computers, ultra-mobile personal computers (UMPCs), netbooks, Personal Digital Assistants (PDAs) and other terminal devices, and the embodiment of the application does not limit the specific types of the terminal devices at all.

For example, the terminal device may be a Station (ST) in a WLAN, which may be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA) device, a handheld device with Wireless communication capability, a computing device or other processing device connected to a Wireless modem, a vehicle-mounted device, a vehicle-mounted networking terminal, a computer, a laptop, a handheld communication device, a handheld computing device, a satellite Wireless device, a Wireless modem card, a television set-top box (STB), a Customer Premises Equipment (CPE), and/or other devices for communicating over a Wireless system and a next generation communication system, such as a Mobile terminal in a 5G Network or a Public Land Mobile Network (future evolved, PLMN) mobile terminals in the network, etc.

By way of example and not limitation, when the terminal device is a wearable device, the wearable device may also be a generic term for intelligently designing daily wearing by applying wearable technology, developing wearable devices, such as glasses, gloves, watches, clothing, shoes, and the like. A wearable device is a portable device that is worn directly on the body or integrated into the clothing or accessories of the user. The wearable device is not only a hardware device, but also realizes powerful functions through software support, data interaction and cloud interaction. The generalized wearable intelligent device has the advantages that the generalized wearable intelligent device is complete in function and large in size, can realize complete or partial functions without depending on a smart phone, such as a smart watch or smart glasses, and only is concentrated on a certain application function, and needs to be matched with other devices such as the smart phone for use, such as various smart bracelets for monitoring physical signs, smart jewelry and the like.

Take the terminal device as a mobile phone as an example. Fig. 1 is a block diagram illustrating a partial structure of a mobile phone according to an embodiment of the present disclosure. Those skilled in the art will appreciate that the handset configuration shown in fig. 1 is not intended to be limiting and may include more or fewer components than those shown, or some components may be combined, or a different arrangement of components.

The following describes each component of the mobile phone in detail with reference to fig. 1:

the terminal load 10 includes RF circuitry 110, memory 120, a display unit 130, an audio system 140, and a processor 150.

The RF circuit 110 may be used for receiving and transmitting signals during information transmission and reception or during a call, and in particular, receives downlink information of a base station and then processes the received downlink information to the processor 180; in addition, the data for designing uplink is transmitted to the base station. Typically, the RF circuitry includes, but is not limited to, an antenna, at least one Amplifier, a transceiver, a coupler, a Low Noise Amplifier (LNA), a duplexer, and the like. In addition, the RF circuitry 110 may also communicate with networks and other devices via wireless communications. The wireless communication may use any communication standard or protocol, including but not limited to Global System for Mobile communication (GSM), General Packet Radio Service (GPRS), Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA), Long Term Evolution (LTE)), e-mail, Short Messaging Service (SMS), and the like.

The memory 120 may be used to store software programs and modules, and the processor 180 executes various functional applications and data processing of the mobile phone by operating the software programs and modules stored in the memory 120. The memory 120 may mainly include a storage program area and a storage data area, wherein the storage program area may store an operating system, an application program required by at least one function (such as a sound playing function, an image playing function, etc.), and the like; the storage data area may store data (such as audio data, a phonebook, etc.) created according to the use of the cellular phone, and the like. Further, the memory 120 may include high speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other volatile solid state storage device.

The display unit 130 may be used to display information input by the user or information provided to the user and various menus of the mobile phone. The Display unit 130 may include a Display panel, and optionally, the Display panel may be configured in the form of a Liquid Crystal Display (LCD), an Organic Light-Emitting Diode (OLED), or the like. Further, the touch panel may cover the display panel, and when the touch panel detects a touch operation thereon or nearby, the touch panel transmits the touch operation to the processor 150 to determine the type of the touch event, and then the processor 150 provides a corresponding visual output on the display panel according to the type of the touch event. Although the touch panel and the display panel can be two separate components to implement the input and output functions of the mobile phone, in some embodiments, the touch panel and the display panel can be integrated to implement the input and output functions of the mobile phone.

The audio system 140 includes audio circuitry, a speaker, and a microphone that provides an audio interface between the user and the handset. The audio circuit can transmit the electric signal converted from the received audio data to the loudspeaker, and the electric signal is converted into a sound signal by the loudspeaker to be output; on the other hand, the microphone converts the collected sound signal into an electrical signal, which is received by the audio circuit and converted into audio data, which is then processed by the audio data output processor 150 and then transmitted to, for example, another cellular phone via the RF circuit 110, or the audio data is output to the memory 120 for further processing.

The processor 150 is a control center of the mobile phone, connects various parts of the entire mobile phone by using various interfaces and lines, and performs various functions of the mobile phone and processes data by operating or executing software programs and/or modules stored in the memory 120 and calling data stored in the memory 120, thereby performing overall monitoring of the mobile phone. Alternatively, processor 150 may include one or more processing units; preferably, the processor 150 may integrate an application processor, which mainly handles operating systems, user interfaces, application programs, etc., and a modem processor, which mainly handles wireless communications. It will be appreciated that the modem processor described above may not be integrated into the processor 150.

The mobile phone 100 further includes a charging port 02 connected to the charger 00, and a charging/discharging port 03 connected to the charging port 02 and the terminal load 01. The handset 100 also includes a battery 40 for powering the various components. The charging/discharging port 03 includes a charging detection circuit 031, a charging protection circuit 032, and a power conversion circuit 033. The charger 00 outputs a charging voltage, the charging port 02 transfers the charging voltage, the charging detection circuit generates a detection signal according to the charging voltage, and the charging protection circuit 032 transfers the charging voltage to the battery 40 according to the detection signal. The battery 40 outputs a battery voltage, and the power conversion circuit 33 generates a supply voltage from the battery voltage to supply power to the end load 10.

The battery 40 includes a battery cell 41, a dual protection control switch 42, a dual protection chip 43, and a charging/discharging interface 44. The battery cell 41 outputs a battery voltage, the dual protection chip 43 generates a control signal, the dual protection control switch 42 communicates the battery voltage or the charging voltage according to the control signal, and the charging/discharging interface 44 switches the battery voltage or the charging voltage.

Fig. 2 is a schematic diagram of a software structure of the mobile phone 100 according to the embodiment of the present application. Taking the operating system of the mobile phone 100 as an Android system as an example, in some embodiments, the Android system is divided into four layers, which are an application layer, an application Framework (FWK) layer, a system layer and a hardware abstraction layer, and the layers communicate with each other through a software interface.

As shown in fig. 2, the application layer may be a series of application packages, which may include short message, calendar, camera, video, navigation, gallery, call, and other applications.

The application framework layer provides an Application Programming Interface (API) and a programming framework for the application programs of the application layer. The application framework layer may include some predefined functions, such as functions for receiving events sent by the application framework layer.

As shown in FIG. 2, the application framework layers may include a window manager, a resource manager, and a notification manager, among others.

The window manager is used for managing window programs. The window manager can obtain the size of the display screen, judge whether a status bar exists, lock the screen, intercept the screen and the like. The content provider is used to store and retrieve data and make it accessible to applications. The data may include video, images, audio, calls made and received, browsing history and bookmarks, phone books, etc.

The resource manager provides various resources for the application, such as localized strings, icons, pictures, layout files, video files, and the like.

The notification manager enables the application to display notification information in the status bar, can be used to convey notification-type messages, can disappear automatically after a short dwell, and does not require user interaction. Such as a notification manager used to inform download completion, message alerts, etc. The notification manager may also be a notification that appears in the form of a chart or scroll bar text at the top status bar of the system, such as a notification of a background running application, or a notification that appears on the screen in the form of a dialog window. For example, prompting text information in the status bar, sounding a prompt tone, vibrating the electronic device, flashing an indicator light, etc.

The application framework layer may further include:

a viewing system that includes visual controls, such as controls to display text, controls to display pictures, and the like. The view system may be used to build applications. The display interface may be composed of one or more views. For example, the display interface including the short message notification icon may include a view for displaying text and a view for displaying pictures.

The phone manager is used to provide the communication functions of the handset 100. Such as management of call status (including on, off, etc.).

The system layer may include a plurality of functional modules. For example: a sensor service module, a physical state identification module, a three-dimensional graphics processing library (such as OpenGL ES), and the like.

The sensor service module is used for monitoring sensor data uploaded by various sensors in a hardware layer and determining the physical state of the mobile phone 100;

the physical state recognition module is used for analyzing and recognizing user gestures, human faces and the like;

the three-dimensional graphic processing library is used for realizing three-dimensional graphic drawing, image rendering, synthesis, layer processing and the like.

The system layer may further include:

the surface manager is used to manage the display subsystem and provide fusion of 2D and 3D layers for multiple applications.

The media library supports a variety of commonly used audio, video format playback and recording, and still image files, among others. The media library may support a variety of audio-video encoding formats, such as MPEG4, h.264, MP3, AAC, AMR, JPG, PNG, and the like.

The hardware abstraction layer is a layer between hardware and software. The hardware abstraction layer may include a display driver, a camera driver, a sensor driver, etc. for driving the relevant hardware of the hardware layer, such as a display screen, a camera, a sensor, etc.

The lithium ion battery charging method provided by the embodiment of the present application can be implemented on the mobile phone 100 having the above hardware structure/software structure.

It should be appreciated that, in the conventional charging method for the li-ion battery, as shown in fig. 3, in the end of charging (the last step or steps of charging), the li-ion battery is first subjected to constant current charging with a first cut-off current I3 (the first cut-off current I3 is about 0.5C) until the charging voltage of the li-ion battery reaches a specified cut-off charging voltage Ux, and then subjected to constant voltage charging with the specified cut-off charging voltage Ux until the charging current of the li-ion battery reaches a second cut-off current I4 (the second cut-off current I4 is between 0.02C and 0.03C), and the specified cut-off charging voltage Ux is generally about 0 to 50mV higher than the rated charging voltage U0 of the li-ion battery. Fig. 4 shows a schematic diagram of changes of charging voltage and charging rate in a charging process of a conventional lithium ion battery charging method, wherein in fig. 4, an abscissa represents charging time, and an ordinate represents charging voltage and charging rate.

On the premise of meeting the rated capacity, the traditional lithium ion battery charging method improves the specified cut-off charging voltage, increases constant-current charging steps, and reduces the constant-voltage charging time at the tail end of charging, thereby improving the charging speed. However, there are two problems with this type of approach: 1) the designated cut-off charging voltage Ux at the charging end is higher than the rated charging voltage U0 of the lithium ion battery, but the corresponding charging rate I3 is not reduced to be within 0.5C, and the lithium ion battery is still charged by using a larger rate above the rated charging voltage U0, so that lithium dendrites are easily separated out from the surface of the negative electrode of the lithium ion battery, the capacity attenuation is accelerated, and meanwhile, the diaphragm can be pierced after the lithium dendrites grow to a certain size, and the short circuit risk is brought. 2) The step of constant voltage charging with high voltage (appointed cut-off charging voltage Ux) is reserved at the tail end of charging, which is equivalent to increasing the high voltage on-site time of the lithium ion battery, so that the risks of oxidation of the anode material of the lithium ion battery and decomposition of electrolyte are enlarged, and the aging of the battery is accelerated.

Therefore, the traditional lithium ion battery charging method can improve the charging speed by increasing the specified cut-off charging voltage to be higher than the rated charging voltage of the lithium ion battery, but the charging tail end still keeps the steps of high-rate constant-current charging and high-voltage constant-voltage charging, and the side reaction of the anode and the electrolyte interface can be triggered, so that the film forming impedance of the electrode and the electrolyte interface can be rapidly increased, the aging of the battery is accelerated, and the service life of the battery is shortened.

Fig. 5 shows a schematic flow chart of a lithium ion battery charging method provided by the present application, which can be applied to the above-mentioned mobile phone 100 by way of example and not limitation. The lithium ion battery charging method comprises the following steps:

s101: and charging the lithium ion battery with the rated charging voltage of the lithium ion battery until the charging current of the lithium ion battery reaches the cut-off charging current.

The rated charging voltage of the lithium ion battery refers to the nominal voltage of the lithium ion battery, the battery can mark a voltage, for example, a dry battery marks 1.5V, some lithium ion batteries mark 3.7V, and a storage battery marks 4.8V, 6V or 12V, and the like, and meanwhile, the rated charging voltage of the lithium ion battery can also refer to the normal working voltage of the lithium ion battery.

The off-charging current refers to a charging current of the battery at the end of charging the battery with the charging voltage.

In one possible implementation, the lithium ion battery is charged at a constant voltage with a rated charging voltage of the lithium ion battery until the charging current of the lithium ion battery reaches a cutoff charging current.

In another possible implementation manner, the lithium ion battery may be charged in a step-wise charging voltage adjustment manner until the charging current of the lithium ion battery reaches the cut-off charging current, wherein a final charging voltage in the step-wise charging voltage adjustment manner is a rated charging voltage of the lithium ion battery.

The charging voltage is adjusted in a stepwise manner, i.e. stepwise constant voltage charging, specifically, the charging voltage is adjusted in a stepwise manner so that the actual charging current curve of the battery approaches the current-voltage curve during charging, as shown in fig. 6.

S102: charging the lithium ion battery with the cut-off charging current until the charging voltage of the lithium ion battery reaches the cut-off charging voltage; wherein the cut-off charging voltage is greater than the rated charging voltage of the lithium ion battery.

The off-charging voltage refers to a charging voltage of the battery at the end of charging the battery with the charging current.

In one possible implementation, the lithium ion battery is charged with a constant current by stopping the charging current until the charging voltage of the lithium ion battery reaches the stopping charging voltage, thereby completing the charging.

In another possible implementation manner, the charging current is adjusted in a stepwise manner to charge the lithium ion battery until the charging voltage of the lithium ion battery reaches the cut-off charging voltage, thereby completing the charging. The initial charging current in the stepwise adjustment charging voltage mode is the cut-off charging current.

The charging current is adjusted in a stepwise manner, i.e. stepwise constant current charging, specifically, the charging current is adjusted in a stepwise manner so that the actual charging voltage curve of the battery approaches the voltage-current curve during the charging process, as shown in fig. 7.

Alternatively, the cutoff charging current may have a value range of (0.02C, 1.5C), and the cutoff charging voltage may have a value range of (U0, U0+200 mV); wherein, U0 is the rated charging voltage of the lithium ion battery.

Preferably, the interval of the value of the off-state charging current may be (0.12C, 0.4C).

A comparison graph of the charging voltage and the charging time variation provided by an embodiment of the present application with the charging voltage and the charging time variation of the prior art is shown in fig. 8, in which the abscissa is the charging time and the ordinate is the charging voltage. The two curves in the upper half of fig. 8 are the voltage variation with charging time of the positive electrode of the lithium ion battery in the prior art and the voltage variation with charging time of the positive electrode of the ion battery in the present application, respectively, and the two curves in the lower half of fig. 8 are the voltage variation with charging time of the lithium ion battery in the prior art, respectivelyThe voltage of the negative electrode of the ion battery changes with the charging time, U0 is rated charging voltage, Uy is cut-off charging voltage of the application, Ux is cut-off charging voltage specified by the prior art, and U_{Negative electrode 1}For the negative cut-off charging voltage of the present application, U_{Negative electrode 2}The charging voltage is cut off for the negative electrode of the prior art. According to the experimental test result, the voltage of the negative electrode of the lithium ion battery is larger than 0V in the whole charging process, namely no dendritic crystal is separated out. This is because the charging terminal cuts off the charging voltage U_xHigher than the rated charging voltage U of the lithium ion battery₀But corresponds to the charging rate I₃Reduced to less than 0.5C at rated charging voltage U₀The lithium ion battery is charged by using a small multiplying power, so that the lithium dendrite is prevented from being separated out from the surface of the negative electrode of the lithium ion battery, the capacity attenuation is accelerated, and the lithium dendrite can pierce the short circuit risk caused by the diaphragm after growing to a certain size.

Furthermore, since the off-charging current (0.02C, 1.5C) of the end-of-charge of the charging scheme of the application example is much higher than the off-charging current (0.02C to 0.03C) of the end-of-charge of the charging scheme of the related art, the charging time is greatly reduced while the same charging capacity is accomplished.

Optionally, as shown in fig. 9, step S101 may further include step S99 and step S100 before.

S99: acquiring the current working condition of the lithium ion battery, wherein the working condition comprises the current ambient temperature of the lithium ion battery and/or the current charging cycle number of the lithium ion battery;

s100: acquiring a charging parameter corresponding to the current working condition from a preset database according to the current working condition of the lithium ion battery; wherein the charging parameters include an off-charge voltage and an off-charge current.

And acquiring charging parameters matched with the charging cycle times and the ambient temperature from a prestored database. The charging parameters in the database correspond to the number of charging cycles and the ambient temperature one to one.

Optionally, as shown in fig. 10, step S99 may be preceded by step S97 and step S98.

S97: and testing corresponding charging parameters of the lithium ion battery under different working conditions.

It should be noted that step S97 may include two cases.

In the first case, step S97 includes steps S97-1a and S97-2 a.

S97-1 a: testing experimental charging time lengths corresponding to different experimental charging parameters of the lithium ion battery under a certain working condition; the experimental charging parameters include an experimental cut-off charging voltage and an experimental cut-off charging current.

S97-2 a: when the experimental charging time corresponding to the experimental charging parameter is less than the preset charging time and the experimental cut-off charging voltage or the experimental cut-off charging current corresponding to the experimental charging parameter is the minimum, taking the experimental charging parameter as the charging parameter corresponding to a certain working condition

It should be noted that, by executing steps S97-1a and S97-2a under different operating conditions, the charging parameters corresponding to the lithium ion battery under different operating conditions can be obtained.

By way of example and not limitation, when the step S97-2a is to use the experimental charging parameter as the charging parameter corresponding to a certain operating condition when the experimental charging duration corresponding to the experimental charging parameter is less than the preset charging duration and the experimental cut-off charging voltage corresponding to the experimental charging parameter is the minimum, the step S97-2a may include the following steps:

a1: the target voltage is set as an initial experiment cut-off charging voltage, and the target current is set as an initial experiment cut-off charging current.

B1: and acquiring the experimental charging time of the lithium ion battery under the target voltage and the target current.

C1: judging whether the experimental charging time is less than the preset charging time or not; if yes, go to step D1; if the determination result is negative, step E1 is executed.

D1: the cutoff charging voltage is set to a target voltage, the cutoff charging current is set to a target current, and the flow steps are terminated.

E1: the target current is updated to the sum of the target current and the step current value.

F1: judging whether the target current is larger than the maximum value of the target current or not; if yes, go to step G1; if the determination result is negative, step B1 is executed.

G1: the target current is set as the initial experiment off-charging current, the target voltage is updated to the sum of the target voltage and the step voltage value, and step H1 is performed.

H1: judging whether the target voltage is greater than the maximum value of the target voltage or not; if the judgment result is yes, ending the flow step; if the determination result is negative, step B1 is executed.

By way of example and not limitation, when the step S97-2a is to use the experimental charging parameter as the charging parameter corresponding to a certain operating condition when the experimental charging duration corresponding to the experimental charging parameter is less than the preset charging duration and the experimental cutoff charging current corresponding to the experimental charging parameter is the minimum, the step S97-2a may include the following steps:

a2: the target voltage is set as an initial experiment cut-off charging voltage, and the target current is set as an initial experiment cut-off charging current.

B2: and acquiring the experimental charging time of the lithium ion battery under the target voltage and the target current.

C2: judging whether the experimental charging time is less than the preset charging time or not; if yes, go to step D2; if the determination result is negative, step E2 is executed.

D2: the cutoff charging voltage is set to a target voltage, the cutoff charging current is set to a target current, and the flow steps are terminated.

E2: the target voltage is updated to the sum of the target voltage and the stepped voltage value.

F2: judging whether the target voltage is greater than the maximum value of the target voltage or not; if yes, go to step G2; if the determination result is negative, step B2 is executed.

G2: the target voltage is set as the initial experiment off-charging voltage, the target current is updated to the sum of the target current and the step current value, and step H2 is executed.

H2: judging whether the target current is larger than the maximum value of the target current or not; if the judgment result is yes, ending the flow step; if the determination result is negative, step B2 is executed.

In the second case, step S97 includes steps S97-1b and S97-2 b.

S97-1 b: testing experimental charging time lengths corresponding to different experimental charging parameters of the lithium ion battery under a certain working condition; the experimental charging parameters include an experimental cut-off charging voltage and an experimental cut-off charging current.

S97-2 b: and when the experimental charging time corresponding to the experimental charging parameter is the minimum, taking the experimental charging parameter as the corresponding charging parameter under a certain working condition.

It should be noted that, by executing steps S97-1b and S97-2b under different operating conditions, the charging parameters corresponding to the lithium ion battery under a plurality of operating conditions can be obtained.

By way of example and not limitation, step S97-2b may include the steps of:

a3: the target voltage is set as an initial experiment cut-off charging voltage, and the target current is set as an initial experiment cut-off charging current.

B3: and acquiring the experimental charging time of the lithium ion battery under the target voltage and the target current.

C3: and acquiring the target charging time length according to the experimental charging time length.

When step C3 is executed for the first time in the loop, step C3 specifically includes: setting the target charging time as an experimental charging time; when the step C3 is not executed for the first time during the loop, the step C3 specifically includes: judging whether the experimental charging time is less than the target charging time; if the experimental charging time is judged to be less than the target charging time, the target charging time is the experimental charging time; if it is determined that the experimental charging period is not less than the target charging period, step D3 is executed.

D3: the target voltage is updated to the sum of the target voltage and the stepped voltage value.

E3: judging whether the target voltage is greater than the maximum value of the target voltage or not; if yes, go to step F3; if the determination result is negative, step B3 is executed.

F3: the target voltage is set as the initial experiment cut-off charging voltage, and the target current is updated to the sum of the target current and the step current value.

G3: judging whether the target current is larger than the maximum value of the target current or not; if yes, go to step H3; if the determination result is negative, step B3 is executed.

H3: and taking the experimental charging parameter corresponding to the target charging time as the charging parameter under the working condition.

S98: and storing the charging parameters and the working conditions obtained by the test into a database in a correlation manner.

In one embodiment, a two-dimensional array is generated to characterize the relationship between the operating conditions and the charging parameters.

For a better understanding of the present application, the lithium battery cell charging method of the present application is explained below by specific examples:

in a first example, a 4.0Ah-4.4V voltage system lithium ion battery is taken as a sample, the charging rate of 1.0C is 4.0A, and the rated charging voltage U0 is 4.4V. Referring to the method shown in fig. 5, a three-electrode battery is manufactured by embedding a lithium reference electrode in the battery in advance, a cut-off charging current is used for charging above the rated charging voltage U0 of the lithium ion battery until the cut-off charging voltage is reached, and according to theoretical calculation and experimental test results, the negative electrode voltage of the lithium ion battery is greater than 0V in the whole charging process, namely no dendrite is separated out. In specific implementation, based on the calibration result of the negative voltage curve in the charging process, on the premise of meeting the requirement of the preset charging time, the minimum cut-off charging voltage is taken as the corresponding scheme (according to the first condition of step 97), and a charging parameter and working condition association database as shown in table 1 is established. The current battery environmental temperature is 25 ℃, the cycle period is 150 cycles, based on the parameters of 25 ℃ and 150 cycles, a charging strategy can be matched in a database shown in table 1, according to the charging strategy, the cut-off charging current I5 is 0.26C, the cut-off charging voltage Uy is the sum of U0 and 55mV, namely the cut-off charging voltage Uy is 4.455V, and therefore the risk of lithium precipitation on the surface of the negative electrode in the whole charging process can be guaranteed.

As shown in table 2, the prior art charging scheme includes the following three phases: 1)1.72C constant current charging to 4.22V, 4.22V constant voltage charging to 1.29C; 2) charging the 1.29C constant current to a rated charging voltage of 4.4V, and charging the 4.4V constant voltage to 0.6C; 3) and (4) charging the battery to a specified cutoff charging voltage of 4.45V by using a 0.6C constant current, and charging the battery to 0.09C by using a 4.45V constant voltage.

The charging scheme of this example includes the following three phases: 1)1.72C constant current charging to 4.22V, 4.22V constant voltage charging to 1.29C; 2) charging the 1.29C constant current to a rated charging voltage of 4.4V, and charging the 4.4V constant voltage to 0.26C; 3) and 0.26C is subjected to constant current charging to a specified cut-off charging voltage of 4.455V, and the charging is finished.

The charging scheme of the present example is supported by the terminal device shown in fig. 1 and the lithium ion battery charging method shown in fig. 5.

Table 1 first example database relating charging parameters and operating conditions

Table 225 ℃ comparison of prior art charging protocol to first example charging protocol

The comparison result of the measured charging data in table 2 and fig. 11 shows that the full charging time corresponding to the charging scheme of the present example is 52.2min at an ambient temperature of 25 ℃, and the charging scheme of the prior art is 65min, which obviously increases the charging speed of the charging method provided by the present example greatly. Meanwhile, the high voltage duration of the charging scheme of this example exceeding the rated charging voltage by 4.4V or more is only 5.3min, whereas the high voltage duration of the prior art charging scheme of 4.4V or more is 30.8 min. Therefore, the charging scheme of the example greatly reduces the duration time of the high voltage on the basis of greatly improving the charging speed, and effectively inhibits the interface side reaction of the anode and the electrolyte, thereby reducing the influence on the service life of the lithium ion battery.

At the ambient temperature of 25 ℃, the low-current constant-current charging is adopted to cut off, the cut-off charging voltage at the tail end (the last step or steps of charging) of the charging is improved, and the high-voltage constant-voltage charging step is removed, so that the influence on the service life of the lithium ion battery can be effectively reduced when the charging speed of the lithium ion battery is increased. In addition, the charging scheme of the present example is adjusted in real-time according to the real-time charging temperature and the number of cycle cycles, thereby maximizing battery life.

For example, in a second example, a 3.0Ah-4.4V voltage system lithium ion battery is used as a sample, the charge rate of 1.0C is 3.0A, and the rated charge voltage U0 is 4.4V. Referring to the method shown in fig. 5, a three-electrode battery is manufactured by embedding a lithium reference electrode in the battery in advance, a cut-off charging current I5 is used for charging above the rated charging voltage U0 of the lithium ion battery, the cut-off charging voltage is Uy, and according to theoretical calculation and experimental test results, the negative electrode voltage of the lithium ion battery is greater than 0V in the whole charging process, namely no dendrite is separated out. In specific implementation, based on the calibration result of the negative voltage curve in the charging process, on the premise of meeting the charging time requirement, the minimum value of the cutoff charging voltage Uy is taken as a corresponding scheme (according to the first condition of step S97), and a charging parameter and working condition association database as shown in table 3 is established. The current battery ambient temperature is 7 ℃ and the cycle period is 160 cycles. Therefore, referring to the implementation flow shown in fig. 5, according to the parameters of 7 ℃ and 160 cycles, a charging strategy can be matched in the database of table 3, according to which the cutoff charging current I5 is 0.17C, the cutoff charging voltage Uy is the sum of U0 and 45mV, that is, the cutoff charging voltage Uy is 4.445V, thereby effectively ensuring that there is no risk of lithium deposition on the cathode surface during the whole charging process.

As shown in table 4, the prior art charging scheme includes the following three phases: 1)1.72C constant current charging to 4.22V, 4.22V constant voltage charging to 1.29C; 2) charging the 1.29C constant current to a rated charging voltage of 4.4V, and charging the 4.4V constant voltage to 0.6C; 3) and (4) charging the battery to a specified cutoff charging voltage of 4.45V by using a 0.6C constant current, and charging the battery to 0.09C by using a 4.45V constant voltage.

The charging scheme of this example includes the following three phases: 1)1.72C constant current charging to 4.22V, 4.22V constant voltage charging to 1.29C; 2) charging the battery to a rated charging voltage of 4.4V by a constant current of 1.29C and charging the battery to 0.17C by a constant voltage of 4.4V; 3) and 0.17C is subjected to constant current charging to a specified cut-off charging voltage of 4.445V, and the charging is finished.

TABLE 3 second example database relating charging parameters to operating conditions

TABLE 47 deg.C comparison of Prior Art charging protocol and inventive charging protocol

The comparison result of the actually measured charging data in fig. 12 and table 4 shows that the full charging time corresponding to the charging scheme of the present example is 59.6min at an ambient temperature of 7 ℃, and the charging scheme of the prior art is 65min, which obviously increases the charging speed of the charging method provided by the present example greatly. Meanwhile, the high voltage duration of the present example charging scheme above the rated charging voltage of 4.4V is 13min, while the high voltage duration of the prior art charging scheme above 4.4V is 30.8 min. Therefore, according to the charging scheme, on the basis of greatly improving the charging speed, the high-voltage duration time is greatly reduced, and the interface side reaction of the anode and the electrolyte is effectively inhibited, so that the influence on the service life of the lithium ion battery is reduced.

As can be seen from the first example and the second example, the lithium ion battery charging method provided by the present application achieves expected beneficial effects at ambient temperatures of 25 ℃ and 7 ℃, so that the lithium ion battery charging method provided by the present application is suitable for different temperature environments.

For example, in a third example, a 3.5Ah-4.42V voltage system lithium ion battery is used as a sample, the charge rate of 1.0C is 3.5A, and the rated charge voltage U0 is 4.42V. Referring to the method shown in fig. 5, a three-electrode battery is manufactured by embedding a lithium reference electrode in the battery in advance, a small current I5 is used for charging above the rated charging voltage U0 of the lithium ion battery, the cut-off charging voltage is Uy, and according to theoretical calculation and experimental test results, the negative electrode voltage of the lithium ion battery is greater than 0V in the whole charging process, namely, no dendrite is separated out. In specific implementation, based on the calibration result of the negative voltage curve in the charging process, on the premise of meeting the charging time requirement, the minimum value of the cut-off charging voltage Uy is taken as a corresponding scheme (according to the first condition of step S97), and a charging parameter and working condition association database as shown in table 5 is established for real-time calling during charging of the terminal device. Taking the current ambient temperature of the battery as 25 ℃ and the cycle period of 300 cycles as an example, referring to the execution flow shown in fig. 5, the charging strategy can be matched in the database in table 5, and according to the charging strategy, the cutoff charging current I5 is 0.34C, the cutoff charging voltage Uy is the sum of U0 and 40mV, that is, the cutoff charging voltage Uy is 4.46V, so that the risk of lithium precipitation on the negative electrode surface in the whole charging process is effectively ensured.

As shown in table 6, the prior art charging scheme includes the following three phases: 1)1.72C constant current charging to 4.27V, 4.27V constant voltage charging to 1.29C; 2) charging the 1.29C to a rated charging voltage of 4.42V by a constant current, and charging the 4.42V to 0.6C by a constant voltage; 3) and the charging is finished when the charging is carried out at 0.6C constant current charging to the specified cutoff charging voltage of 4.47V and at 4.47V constant voltage charging to 0.09C.

The charging scheme of this example includes the following three phases: 1)1.72C constant current charging to 4.27V, 4.27V constant voltage charging to 1.29C; 2) charging the 1.29C to a rated charging voltage of 4.42V by constant current, and charging the 4.42V to 0.34C by constant voltage; 3) and (5) performing constant current charging to the specified cutoff charging voltage of 4.46V at 0.34C, and completing the charging.

TABLE 5 third example database relating charging parameters and operating conditions

TABLE 625 deg.C Prior Art charging protocol vs. inventive charging protocol

The comparison result of the measured charging data in fig. 13 and table 5 shows that the full charging time corresponding to the charging scheme of the present example is 43.5min at an ambient temperature of 25 ℃, and the charging scheme of the prior art is 65min, which obviously increases the charging speed of the charging method provided by the present example greatly. Meanwhile, the high voltage duration of the present example charging scheme above the rated charging voltage of 4.4V is 5.9min, while the high voltage duration of the prior art charging scheme above 4.4V is 30.8 min. Therefore, according to the charging scheme, on the basis of greatly improving the charging speed, the high-voltage duration time is greatly reduced, and the interface side reaction of the anode and the electrolyte is effectively inhibited, so that the influence on the service life of the lithium ion battery is reduced.

Therefore, the high-voltage 4.42V system lithium ion battery can also shorten the charging time by improving the cut-off charging voltage at the tail end of charging and cutting off the low-current constant-current charging, so that the influence on the service life of the lithium ion battery is reduced when the charging speed of the lithium ion battery is increased.

As can be seen from the first example and the third example, the lithium ion battery with the voltage system of 4.0Ah to 4.4V and the lithium ion battery with the voltage system of 3.5Ah to 4.42V both achieve the expected beneficial effects by applying the charging method for the lithium ion battery provided by the present application, so that the charging method for the lithium ion battery provided by the present application is suitable for the lithium ion batteries with different rated voltage specifications.

For example, in the fourth example, a 4.0Ah-4.4V voltage system lithium ion battery was used as a sample, the charge rate of 1.0C was 4.0A, and the rated charge voltage U0 was 4.4V. Referring to the method shown in fig. 5, a three-electrode battery is manufactured by embedding a lithium reference electrode in the battery in advance, a cut-off charging current I5 is used for charging above the rated charging voltage U0 of the lithium ion battery, the cut-off charging voltage is Uy, and according to theoretical calculation and experimental test results, the negative electrode voltage of the lithium ion battery is greater than 0V in the whole charging process, namely no dendrite is separated out. In specific implementation, based on the calibration result of the negative voltage curve in the charging process, on the premise of meeting the requirement of charging time, a smaller value of the cut-off charging current I5 is taken as a corresponding scheme, and a charging parameter and working condition association database shown in table 7 is established for real-time calling during charging of the terminal device. Taking the current ambient temperature of the battery as 25 ℃ and the cycle period of 250 cycles as an example, referring to the execution flow shown in fig. 5, the charging strategy can be matched with the database in table 7, and according to the charging strategy, the cutoff charging current I5 is 0.34C, and the cutoff charging voltage Uy is the sum of U0 and 44mV, that is, the cutoff charging voltage is 4.44V, so that no risk of lithium precipitation on the negative electrode surface in the whole charging process is effectively ensured.

As shown in table 8, the prior art charging scheme includes the following three phases: 1) charging the battery to a rated charging voltage of 4.40V by a constant current of 1.29C and charging the battery to 0.6C by a constant voltage of 4.40V; 2) and (4) charging the battery to a specified cutoff charging voltage of 4.45V by using a 0.6C constant current, and charging the battery to 0.09C by using a 4.45V constant voltage.

The charging scheme of this example includes the following three phases: 1) charging the 1.29C to a rated charging voltage of 4.40V by constant current, and charging the 4.40V to 0.34C by constant voltage; 2) and (5) performing constant current charging to the specified cutoff charging voltage of 4.44V at 0.34C, and completing the charging.

The charging scheme of the present example is supported by the terminal device shown in fig. 3 and the lithium ion battery charging method shown in fig. 5.

Table 7 database relating charge parameters and operating conditions of the fourth example

Table 825 ℃ comparison of prior art charging protocol and inventive charging protocol

Based on the current 25 ℃ and 250cycle parameters, the matched charge tip charging strategy (0.34C, 4.44V) in the database shown in table 7 was within the negative lithiation charging boundary. Therefore, according to the charging scheme, on the basis of greatly improving the charging speed, the high-voltage constant-voltage charging step is eliminated, so that the side reaction of the positive electrode and the electrolyte interface can be effectively inhibited, and the influence on the service life of the lithium ion battery can be reduced.

In a common constant-current charging or constant-voltage charging scene, the charging time can be shortened by increasing the cut-off charging voltage at the tail end of charging and adopting a low-current constant-current charging cut-off, so that the influence on the service life of the lithium ion battery is reduced when the charging speed of the lithium ion battery is increased.

As can be seen from the first example and the fourth example, the lithium ion battery charging method provided by the present application achieves expected beneficial effects by adopting a step-wise charging voltage/current adjustment mode or a constant voltage/constant current charging mode, so that the lithium ion battery charging method provided by the present application is applicable to different charging modes.

It should be understood that, the sequence numbers of the steps in the foregoing embodiments do not imply an execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

Fig. 14 shows a structural block diagram of a lithium ion battery charging device provided in the embodiment of the present application, corresponding to the lithium ion battery charging method described in the foregoing embodiment, and only shows portions related to the embodiment of the present application for convenience of description.

Referring to fig. 14, the lithium ion battery charging apparatus 30 includes a voltage charging module 310 and a current charging module 320.

The voltage charging module 310 is configured to charge the lithium ion battery with the rated charging voltage of the lithium ion battery until the charging current of the lithium ion battery reaches the cut-off charging current.

A current charging module 320, configured to charge the lithium ion battery with a cut-off charging current until a charging voltage of the lithium ion battery reaches a cut-off charging voltage; wherein the cut-off charging voltage is greater than the rated charging voltage of the lithium ion battery.

In another embodiment, as shown in fig. 15, the lithium ion battery charging apparatus 30 may further include an operating condition obtaining module 330 and a charging parameter obtaining module 340.

The working condition obtaining module 330 is configured to obtain a current working condition of the lithium ion battery, where the working condition includes a current ambient temperature of the lithium ion battery and/or a current charging cycle number of the lithium ion battery.

A charging parameter obtaining module 340, configured to obtain, according to a current working condition of the lithium ion battery, a charging parameter corresponding to the current working condition from a preset database; wherein the charging parameters include an off-charge voltage and an off-charge current.

In another embodiment, as shown in fig. 16, the li-ion battery charging device 30 may further include a charging parameter testing module 350 and a storage module 360.

And the charging parameter testing module 350 is configured to test charging parameters corresponding to different working conditions of the lithium ion battery.

And the storage module 360 is used for storing the tested charging parameters and working conditions in a database in an associated manner.

There are two situations for the charging parameter testing module 350.

In the first case, as shown in fig. 17, the charging parameter testing module 350 includes a first charging period testing module 351a and a first charging parameter determining module 352 a.

The first charging duration testing module 351a is used for testing experimental charging durations corresponding to different experimental charging parameters of the lithium ion battery under a certain working condition; the experimental charging parameters include an experimental cut-off charging voltage and an experimental cut-off charging current.

The first charging parameter determining module 352a is configured to, when an experimental charging duration corresponding to an experimental charging parameter is less than a preset charging duration and an experimental cut-off charging voltage corresponding to the experimental charging parameter or the experimental cut-off charging current is minimum, use the experimental charging parameter as a corresponding charging parameter under a certain working condition.

In the second case, as shown in fig. 18, the charging parameter testing module 350 includes a second charging period testing module 351b and a second charging parameter determining module 352 b.

The second charging duration testing module 351b is used for testing experimental charging durations corresponding to different experimental charging parameters of the lithium ion battery under a single working condition; the experimental charging parameters include an experimental cut-off charging voltage and an experimental cut-off charging current.

The second charging parameter determining module 352b is configured to, when the experimental charging duration corresponding to the experimental charging parameter is the minimum, take the experimental charging parameter as the charging parameter corresponding to the working condition.

The voltage charging module 310 is specifically configured to: charging the lithium ion battery in a step-type charging voltage adjusting mode until the charging current of the lithium ion battery reaches a cut-off charging current, wherein the final charging voltage in the step-type charging voltage adjusting mode is the rated charging voltage of the lithium ion battery;

the current charging module 320 is specifically configured to: and charging the lithium ion battery in a step-type charging current adjusting mode until the charging voltage of the lithium ion battery reaches a cut-off charging voltage, wherein the initial charging current in the step-type charging current adjusting mode is the cut-off charging current.

The numerical range of the cut-off charging current is (0.02C, 1.5C), and the numerical range of the cut-off charging voltage is (U0, U0+200 mV); wherein, U0 is the rated charging voltage of the lithium ion battery.

It should be noted that, for the information interaction, execution process, and other contents between the above-mentioned devices/units, the specific functions and technical effects thereof are based on the same concept as those of the embodiment of the method of the present application, and specific reference may be made to the part of the embodiment of the method, which is not described herein again.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned division of the functional units and modules is illustrated, and in practical applications, the above-mentioned function distribution may be performed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules, so as to perform all or part of the functions described above. Each functional unit and module in the embodiments may be integrated in one processing unit, or each unit may exist alone physically, or two or more units are integrated in one unit, and the integrated unit may be implemented in a form of hardware, or in a form of software functional unit. In addition, specific names of the functional units and modules are only for convenience of distinguishing from each other, and are not used for limiting the protection scope of the present application. The specific working processes of the units and modules in the system may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

An embodiment of the present application further provides a network device, where the network device includes: at least one processor, a memory, and a computer program stored in the memory and executable on the at least one processor, the processor implementing the steps of any of the various method embodiments described above when executing the computer program.

The embodiments of the present application further provide a computer-readable storage medium, where a computer program is stored, and when the computer program is executed by a processor, the computer program implements the steps that can be implemented in the above method embodiments.

The embodiments of the present application provide a computer program product, which when running on a mobile terminal, enables the mobile terminal to implement the steps in the above method embodiments when executed.

Fig. 19 is a schematic structural diagram of a lithium ion battery charging apparatus/terminal device according to an embodiment of the present application. As shown in fig. 19, the lithium-ion battery charging apparatus/terminal device 19 of this embodiment includes: at least one processor 190 (only one processor is shown in fig. 19), a memory 191, and a computer program 192 stored in memory 191 and executable on at least one processor 190, the steps in any of the various lithium ion battery charging method embodiments described above being implemented by processor 190 when computer program 192 is executed by processor 190.

The lithium ion battery charging device/terminal 19 may be a computing device such as a desktop computer, a notebook, a palm top computer, and a cloud server. The lithium ion battery charging apparatus/terminal device may include, but is not limited to, a processor 190 and a memory 191. It will be understood by those skilled in the art that fig. 19 is merely an example of the li-ion battery charging apparatus/terminal device 19, and does not constitute a limitation of the li-ion battery charging apparatus/terminal device 19, and may include more or less components than those shown, or some components in combination, or different components, such as input-output devices, network access devices, etc.

The Processor 190 may be a Central Processing Unit (CPU), and the Processor 190 may be other general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic, discrete hardware components, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The storage 191 may be, in some embodiments, an internal storage unit of the lithium ion battery charging apparatus/terminal device 19, such as a hard disk or a memory of the lithium ion battery charging apparatus/terminal device 19. The memory 191 may be an external storage device of the lithium ion battery charging apparatus/terminal device 19 in other embodiments, such as a plug-in hard disk provided on the lithium ion battery charging apparatus/terminal device 19, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), and the like. Further, the memory 191 may also include both internal storage elements of the lithium ion battery charging apparatus/terminal device 19 and external storage devices. The memory 191 is used for storing an operating system, an application program, a BootLoader (BootLoader), data, and other programs, such as program codes of a computer program. The memory 191 may also be used to temporarily store data that has been output or is to be output.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, all or part of the processes in the methods of the embodiments described above can be implemented by a computer program, which can be stored in a computer readable storage medium and used by a processor to implement the steps of the embodiments of the methods described above. Wherein the computer program comprises computer program code, which may be in the form of source code, object code, an executable file or some intermediate form, etc. The computer readable medium may include at least: any entity or apparatus capable of carrying computer program code to a terminal device, recording medium, computer Memory, Read-Only Memory (ROM), Random-Access Memory (RAM), electrical carrier wave signals, telecommunications signals, and software distribution medium. Such as a usb-disk, a removable hard disk, a magnetic or optical disk, etc. In certain jurisdictions, computer-readable media may not be an electrical carrier signal or a telecommunications signal in accordance with legislative and patent practice.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and reference may be made to the related descriptions of other embodiments for parts that are not described or illustrated in a certain embodiment.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus/network device and method may be implemented in other ways. For example, the above-described apparatus/network device embodiments are merely illustrative, and for example, a module or a unit may be divided into only one logical function, and may be implemented in other ways, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

Units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.

Claims

1. A method of charging a lithium ion battery, comprising:

2. The method of charging a lithium ion battery of claim 1, further comprising, prior to said charging the lithium ion battery to a cutoff charging current at a lithium ion battery nominal charging voltage:

acquiring the current working condition of the lithium ion battery, wherein the working condition comprises the current ambient temperature of the lithium ion battery and/or the current charging cycle number of the lithium ion battery;

acquiring a charging parameter corresponding to the current working condition from a preset database according to the current working condition of the lithium ion battery; wherein the charging parameters include the cutoff charging voltage and the cutoff charging current.

3. The method of charging a lithium ion battery of claim 2, further comprising, prior to obtaining the current operating conditions of the lithium ion battery:

testing corresponding charging parameters of the lithium ion battery under different working conditions;

and storing the charging parameters and the working conditions obtained by the test into the database in an associated manner.

4. The method for charging a lithium ion battery according to claim 3, wherein the testing the corresponding charging parameters of the lithium ion battery under different working conditions comprises:

testing the experimental charging time lengths corresponding to different experimental charging parameters of the lithium ion battery under a certain working condition; the experimental charging parameters comprise experimental cut-off charging voltage and experimental cut-off charging current;

and when the experimental charging time corresponding to the experimental charging parameter is less than the preset charging time and the experimental cut-off charging voltage or the experimental cut-off charging current corresponding to the experimental charging parameter is the minimum, taking the experimental charging parameter as the charging parameter corresponding to the certain working condition.

5. The method for charging a lithium ion battery according to claim 3, wherein the testing the corresponding charging parameters of the lithium ion battery under different working conditions comprises:

and when the experimental charging time corresponding to the experimental charging parameter is the minimum, taking the experimental charging parameter as the charging parameter corresponding to the certain working condition.

6. The method of claim 1, wherein the step of charging the lithium ion battery at the lithium ion battery rated charging voltage with a constant voltage until the charging current of the lithium ion battery reaches the cutoff charging current comprises:

charging the lithium ion battery in a step-type charging voltage adjusting mode until the charging current of the lithium ion battery reaches a cut-off charging current, wherein the final charging voltage in the step-type charging voltage adjusting mode is the rated charging voltage of the lithium ion battery;

the performing constant-current charging on the lithium ion battery with the cut-off charging current until the charging voltage of the lithium ion battery reaches the cut-off charging voltage comprises:

and charging the lithium ion battery in a step-type charging current adjusting mode until the charging voltage of the lithium ion battery reaches a cut-off charging voltage, wherein the initial charging current in the step-type charging current adjusting mode is the cut-off charging current.

7. The method of claim 1, wherein the cutoff charging current has a value range of (0.02C, 1.5C), and the cutoff charging voltage has a value range of (U0, U0+200 mV); wherein U0 is the rated charging voltage of the lithium ion battery.

8. A lithium ion battery charging device, comprising:

9. A terminal device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that the processor implements the method according to any of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium, in which a computer program is stored which, when being executed by a processor, carries out the method according to any one of claims 1 to 7.