CN112542626A

CN112542626A - Built-in battery of mobile terminal and preparation method

Info

Publication number: CN112542626A
Application number: CN201910894587.8A
Authority: CN
Inventors: 杜思红
Original assignee: Beijing Xiaomi Mobile Software Co Ltd
Current assignee: Beijing Xiaomi Mobile Software Co Ltd
Priority date: 2019-09-20
Filing date: 2019-09-20
Publication date: 2021-03-23

Abstract

The present disclosure discloses a built-in battery of a mobile terminal and a method for manufacturing the same, the built-in battery includes: naked electric core and electric core encapsulated layer, this built-in battery still includes: the heat equalizing layer is arranged between the naked electric core and the electric core packaging layer, bonds the naked electric core and the electric core packaging layer, and equalizes heat of the heat emitted by the naked electric core, wherein the heat conductivity coefficient of the heat equalizing layer is larger than a preset threshold value; the cooling layer is arranged on the outer surface of the battery cell packaging layer and used for absorbing heat and cooling. The heat equalizing layer is arranged in the built-in battery, so that heat is equalized from the surface of a heat source, and the reduction of the overall temperature of the built-in battery is facilitated; the surface temperature of the built-in battery is effectively reduced through the cooling layer outside the built-in battery. The structural design of 'internal soaking + external cooling' provides a better solution to the thermal problem caused by the rapid charging technology.

Description

Built-in battery of mobile terminal and preparation method

Technical Field

The disclosure relates to the technical field of batteries, in particular to a built-in battery of a mobile terminal and a preparation method thereof.

Background

In the technical field of batteries, the charging speed is an important performance index of a built-in battery for a mobile terminal, and in order to meet the extreme charging experience of a user, the charging speed of the battery is faster and faster. At the same time, thermal problems due to rapid charging are becoming more and more prominent.

When the battery is charged, the temperature distribution on the surface of the battery is uneven under the influence of comprehensive factors such as current density distribution, local contact impedance unevenness and the like. The problem of local high temperature not only influences key performance such as the cycle life of battery, and when the position that the heat was concentrated was close with the temperature-sensing device distance of battery protection shield moreover, the charging temperature restriction stage that the charging phase can get into the complete machine fast, is difficult to realize quick charge's technical goal. In order to solve the problem, in the related art, a heat dissipation plate is arranged inside a battery core, so that heat inside the battery is dissipated and conducted, and the heat is dissipated to the outside of the battery.

By adopting the technology, the heat balance in the built-in battery during quick charging can be realized only, and the reduction of the overall temperature of the built-in battery can not be effectively realized.

Disclosure of Invention

The built-in battery of the mobile terminal and the preparation method thereof are provided, and the heat problem caused by a quick charging technology can be solved by arranging the heat equalizing layer in the built-in battery and arranging the cooling layer outside the built-in battery, so that the safety and the cycle performance of the built-in battery are improved.

According to an aspect of the present disclosure, there is provided an internal battery of a mobile terminal, the internal battery including: naked electric core and electric core encapsulated layer, this built-in battery still includes:

the heat-equalizing layer is arranged between the naked electric core and the electric core packaging layer, bonds the naked electric core and the electric core packaging layer, and performs heat equalization on heat dissipated by the naked electric core, wherein the heat conductivity coefficient of the heat-equalizing layer is greater than a preset threshold value;

the cooling layer is arranged on the outer surface of the battery cell packaging layer and used for absorbing heat and cooling.

In an alternative embodiment, the cooling layer comprises a cooling material; the cooling material comprises: phase change materials, or thermoelectric materials; the phase change material comprises at least one of silicon dioxide, aluminum oxide and calcium oxide.

In an optional embodiment, an adhesive layer is included between the cell packaging layer and the cooling layer.

In an alternative embodiment, the combined thickness of the temperature reduction layer and the adhesive layer is between 0.2 millimeters and 2.0 millimeters, inclusive.

In an alternative embodiment, the adhesive of the adhesive layer includes at least one of a rubber-based adhesive, a polyamide-based adhesive, a polypropylene-based adhesive, and a polyethylene-based adhesive.

In an alternative embodiment, the heat spreader layer comprises a viscous coating; the viscous coating comprises: any one of a graphene heat conduction layer, a graphite heat conduction layer, a silicon heat conduction layer and heat conduction gel.

In an alternative embodiment, the thermal spreader has a thickness between 0.5 mm and 2.0 mm, inclusive.

According to an aspect of the present disclosure, there is provided a mobile terminal characterized in that the mobile terminal incorporates the built-in battery as described in the above aspect.

In an alternative embodiment, the mobile terminal is a mobile terminal supporting a fast charging mode; when the mobile terminal is in a quick charging mode for charging, the charging multiplying power is larger than 1 coulomb.

In an alternative embodiment, the mobile terminal is a mobile terminal supporting a super fast charging mode; and when the mobile terminal is in a super quick charging mode for charging, the charging multiplying power is more than 3 coulombs.

The beneficial effect that technical scheme that this disclosure provided brought includes at least:

the heat equalizing layer is arranged in the built-in battery, so that heat is equalized from the surface of a heat source, and the reduction of the overall temperature of the built-in battery is facilitated; the surface temperature of the built-in battery is effectively reduced through the cooling layer outside the built-in battery. This internal soaking, external cooling structural design provides a better solution to the thermal problem that rapid charging techniques result in.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.

Fig. 1 is a cross-sectional view of a built-in battery of a mobile terminal according to an exemplary embodiment of the present disclosure;

fig. 2 is a front view of a built-in battery of a mobile terminal according to an exemplary embodiment of the present disclosure;

fig. 3 is a schematic diagram of a mobile terminal according to an exemplary embodiment of the disclosure;

fig. 4 is a schematic diagram of a mobile terminal according to an exemplary embodiment of the disclosure.

Detailed Description

To make the objects, technical solutions and advantages of the present disclosure more apparent, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

Fig. 1 is a cross-sectional view illustrating an internal battery of a mobile terminal according to an exemplary embodiment of the present disclosure, the internal battery including: naked electric core 101 and electric core encapsulated layer 102, this built-in battery still includes:

the heat-conducting and heat-insulating integrated circuit is arranged between a naked battery cell 101 and a battery cell packaging layer 102, the naked battery cell 101 and the battery cell packaging layer 102 are bonded, and a heat-insulating layer 103 is used for insulating heat emitted by the naked battery cell 101, wherein the heat-conducting coefficient of the heat-insulating layer 103 is greater than a preset threshold value;

and the cooling layer 104 is arranged on the outer surface of the battery cell packaging layer 102 and used for absorbing heat and cooling.

Optionally, the soaking layer 103 is a layer for equalizing the temperature of the bare cell 101, eliminating local high temperature.

Optionally, the temperature reduction layer 104 is a layer for storing, absorbing, and dissipating heat to the surface of the internal battery.

The thermal conductivity is the heat transferred by a 1-square-meter area within 1 second for a 1-meter thick material with a temperature difference of 1 degree between the two side surfaces under a stable heat transfer condition. In summary, the heat equalizing layer is arranged inside the built-in battery, and the cooling layer is arranged outside the built-in battery, so that the heat problem caused by the rapid charging technology can be solved, and the safety and the cycle performance of the built-in battery are improved.

Fig. 2 illustrates a front view of a built-in battery of a mobile terminal according to an exemplary embodiment of the present disclosure, the built-in battery including: naked electric core 201, electric core encapsulation layer 202, soaking layer 203 and cooling layer 204.

Optionally, the cooling layer 204 includes a cooling material. The cooling material comprises: phase change materials, or thermoelectric materials.

The phase change material is a substance which changes the state of a substance under the condition of constant temperature and can provide latent heat. The process of changing physical properties is called a phase change process, and in this case, the phase change material absorbs or releases a large amount of latent heat.

The thermoelectric material refers to a material having a large thermoelectric effect, and is also called a thermoelectric material. It can directly convert heat energy into electric energy or directly produce refrigeration by electric energy.

Illustratively, when the temperature reducing material is a phase change material, the phase change material comprises at least one of silicon dioxide, aluminum oxide and calcium oxide.

Illustratively, when the thermoelectric material is used as the temperature reducing material, the thermoelectric material includes at least one of bismuth telluride and alloys thereof, lead telluride and alloys thereof, and silicon germanium alloys.

Optionally, the total thickness of the temperature reduction layer 204 and the adhesive layer is between 0.2 mm and 2.0 mm, inclusive.

Optionally, an adhesive layer is included between the cell encapsulation layer 202 and the cooling layer 204.

The adhesive of the adhesive layer may include at least one of a rubber-based adhesive, a polyamide-based adhesive, a polypropylene-based adhesive, and a polyethylene-based adhesive.

The rubber adhesive is a synthetic adhesive prepared by using synthetic rubber as a base material. The adhesive has low bonding strength and poor heat resistance, belongs to a non-structural adhesive, but has excellent elasticity, convenient use and strong initial adhesion. The adhesive can be used for bonding soft materials such as rubber, plastic, fabric, leather, wood and the like, or bonding two materials with larger difference of thermal expansion coefficients such as metal-rubber and the like, and is an indispensable material for industrial departments such as machinery, traffic, buildings, textiles, plastics, rubber and the like.

The polyamide adhesive is prepared by condensation polymerization of dibasic acid and diamine, has good drug resistance, and can resist acid and alkali, vegetable oil, mineral oil and the like. Because the molecule of the adhesive has polar groups such as amino, carbonyl, amide and the like, the adhesive has good gluing performance on plastics such as wood, pottery, paper, cloth, brass, aluminum, phenolic resin, polyester resin, polyethylene and the like.

Polypropylene adhesives polymerize very easily under the action of light, heat and initiator, can form a water-resistant film with good gloss, are firm in adhesion, difficult to peel, flexible and elastic at room temperature, good in weather resistance, but not high in tensile strength.

The polyethylene binder is a thermoplastic resin obtained by polymerizing ethylene. In industry, copolymers of ethylene with small amounts of alpha-olefins are also included. It is odorless, non-toxic, has hand feeling similar to wax, and has excellent low temperature resistance and good chemical stability.

Optionally, the soaking layer 203 comprises a viscous coating; the viscous coating comprises: any one of a graphene heat conduction layer, a graphite heat conduction layer, a silicon heat conduction layer and heat conduction gel.

Illustratively, when the graphite adhesive layer is used as the adhesive coating of the thermal uniforming layer 203, the main component is graphite, and the granularity is controlled within 50 microns.

Optionally, when the graphene heat conduction layer or the graphite heat conduction layer or the silicon heat conduction layer is used as the adhesive coating, an adhesive exists in the adhesive coating; the adhesive comprises at least one of a rubber adhesive, a polyamide adhesive, a polypropylene adhesive and a polyethylene adhesive.

When the thermally conductive gel is used as the adhesive coating, the thermally conductive gel itself has adhesiveness and does not need to be added with an adhesive.

Optionally, the thickness of the soaking layer 203 is between 0.5 mm and 2.0 mm, inclusive.

Optionally, the cell encapsulation layer 202 is an aluminum-plastic film or a metal shell; the metal shell comprises a steel shell, an aluminum shell and a plastic shell.

The packaging of the bare cell 201 is divided into two categories, one is a metal case cell and the other is a soft-package cell. The metal shell battery cell comprises a steel shell, an aluminum shell and a plastic shell. The soft package battery cell is a battery cell using an aluminum plastic film as a packaging material.

Optionally, the bare cell 201 includes a lithium ion cell.

The lithium ion battery cell has the advantages of high working voltage, high specific energy, long cycle life and no memory effect, and is widely applied to the field of electronic equipment.

In the electrochemical reaction process of the built-in battery, heat diffuses outwards from the bare cell 201. The soaking layer 203 can be effectively contacted with the naked electric core 201, so that a quick soaking effect is achieved, and the risk of overlarge local temperature rise is eliminated, so that the temperature is uniform when heat is transferred to the surface of the built-in battery. The heat equalizing layer 203 has certain bonding performance, can effectively bond the battery cell packaging layer 202 and the naked battery cell 201, can replace a hot melt adhesive layer commonly used in the current battery cell, cannot cause occupation of a battery space, and effectively solves the problem of loss of energy density of the battery cell due to introduction of a heat dissipation structure. In addition, carry out the actual temperature of soaking design can effective quick reduction naked electric core 201 body from built-in battery inside, improve naked electric core 201's cyclicity can, realize higher economic benefits.

When the heat in the internal battery is transferred to the surface of the internal battery, the cooling layer 204 can effectively absorb and store the heat, so as to reduce the surface temperature of the internal battery and maintain the internal battery within a constant temperature range. Meanwhile, the cooling layer 204 has small thickness and occupies small space, so that the introduction of an external heat sink cannot influence the volume energy density of the battery.

In summary, the built-in battery of the mobile terminal provided by this embodiment is internally provided with the soaking layer, so that soaking is performed from the surface of the heat source, which is beneficial to reducing the overall temperature of the built-in battery; through the outside cooling layer, the surface temperature of the built-in battery is effectively reduced. The internal soaking and external cooling structural design provides a better solution to the thermal problem of the battery rapid charging technology.

In addition, the technical scheme provided by the disclosure can effectively realize the temperature control of the surface of the battery during large-current charging, and improve the safety, the cycle performance and the like of the battery. Meanwhile, the structure is simple in design and manufacture, low in cost, easy to realize large-scale production and convenient for practical application of quick-filling products.

Fig. 3 is a schematic diagram of a mobile terminal having a battery as shown in fig. 1 or fig. 2 built therein according to an exemplary embodiment of the present disclosure.

Optionally, the mobile terminal is a mobile terminal supporting a fast charging mode; when the mobile terminal is in a quick charging mode for charging, the charging multiplying power is larger than 1 coulomb.

Optionally, the mobile terminal is a mobile terminal supporting a super fast charging mode; and when the mobile terminal is in a super quick charging mode for charging, the charging multiplying power is more than 3 coulombs.

The mobile terminal may be a mobile phone, a computer, a digital broadcast terminal, a messaging device, a game console, a tablet device, a medical device, a fitness device, a personal digital assistant, or the like.

Illustratively, a mobile phone is taken as the mobile terminal. When the mobile phone is charged, the electric energy enters the mobile phone and is processed by a voltage reduction circuit in the mobile phone, and then voltage is output to charge the battery, and the voltage conversion and voltage reduction process is carried out by a charging management module in the mobile phone. There is a certain loss in this process, and the loss becomes heat transfer. The faster the charging speed, the higher the power, the more heat is dissipated. When the built-in battery of the mobile phone is the built-in battery with the heat dissipation function as in the embodiment, the heat problem of the quick charging can be well solved by soaking the inside of the battery and cooling the outside of the battery under the condition of the quick charging.

Referring to fig. 4, the mobile terminal illustrated in fig. 3 may include one or more of the following components: processing component 402, memory 404, power component 406, multimedia component 408, audio component 410, input/output (I/O) interface 412, sensor component 414, and communication component 416.

The processing component 402 generally controls overall operation of the mobile terminal, such as operations associated with display, telephone calls, data communications, camera operations, and recording operations. The processing component 402 may include one or more processors 420 to execute instructions to perform all or a portion of the steps of the methods described above. Further, the processing component 402 can include one or more modules that facilitate interaction between the processing component 402 and other components. For example, the processing component 402 can include a multimedia module to facilitate interaction between the multimedia component 408 and the processing component 402.

The memory 404 is configured to store various types of data to support operation at the mobile terminal. Examples of such data include instructions for any application or method operating on the mobile terminal, contact data, phonebook data, messages, pictures, videos, and the like. The memory 404 may be implemented by any type or combination of volatile or non-volatile memory devices such as Static Random Access Memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic or optical disks.

The power supply component 406 provides power to the various components of the mobile terminal. The power components 406 may include a power management system, one or more power sources, and other components associated with generating, managing, and distributing power for the mobile terminal.

The multimedia component 408 includes a screen providing an output interface between the mobile terminal and the user. In some embodiments, the screen may include a Liquid Crystal Display (LCD) and a Touch Panel (TP). If the screen includes a touch panel, the screen may be implemented as a touch screen to receive an input signal from a user. The touch panel includes one or more touch sensors to sense touch, slide, and gestures on the touch panel. The touch sensor may not only sense the boundary of a touch or slide action, but also detect the duration and pressure associated with the touch or slide operation. In some embodiments, the multimedia component 408 includes a front facing camera and/or a rear facing camera. The front camera and/or the rear camera may receive external multimedia data when the mobile terminal is in an operation mode, such as a photographing mode or a video mode. Each front camera and rear camera may be a fixed optical lens system or have a focal length and optical zoom capability.

The audio component 410 is configured to output and/or input audio signals. For example, the audio component 410 includes a Microphone (MIC) configured to receive external audio signals when the mobile terminal is in an operating mode, such as a call mode, a recording mode, and a voice recognition mode. The received audio signals may further be stored in the memory 404 or transmitted via the communication component 416. In some embodiments, audio component 410 also includes a speaker for outputting audio signals.

The I/O interface 412 provides an interface between the processing component 402 and peripheral interface modules, which may be keyboards, click wheels, buttons, etc. These buttons may include, but are not limited to: a home button, a volume button, a start button, and a lock button.

The sensor component 414 includes one or more sensors for providing various aspects of state assessment for the mobile terminal. For example, the sensor component 414 may detect an open/closed state of the mobile terminal, the relative positioning of components, such as a display and keypad of the mobile terminal, the sensor component 414 may also detect a change in the position of the mobile terminal or a component of the mobile terminal, the presence or absence of user contact with the mobile terminal, orientation or acceleration/deceleration of the mobile terminal, and a change in the temperature of the mobile terminal. The sensor assembly 414 may include a proximity sensor configured to detect the presence of a nearby object without any physical contact. The sensor assembly 414 may also include a light sensor, such as a CMOS or CCD image sensor, for use in imaging applications. In some embodiments, the sensor assembly 414 may also include an acceleration sensor, a gyroscope sensor, a magnetic sensor, a pressure sensor, or a temperature sensor.

The communication component 416 is configured to facilitate communications between the mobile terminal and other devices in a wired or wireless manner. The mobile terminal may access a wireless network based on a communication standard, such as Wi-Fi, 2G or 3G, or a combination thereof. In an exemplary embodiment, the communication component 416 receives broadcast signals or broadcast related information from an external broadcast management system via a broadcast channel. In an exemplary embodiment, the communication component 416 further includes a Near Field Communication (NFC) module to facilitate short-range communications.

In an exemplary embodiment, the mobile terminal may be implemented by one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), controllers, micro-controllers, microprocessors or other electronic components for performing the above-described methods.

In an exemplary embodiment, a non-transitory computer-readable storage medium comprising instructions, such as the memory 404 comprising instructions, executable by the processor 420 of the mobile terminal to perform the above-described method is also provided. For example, the non-transitory computer readable storage medium may be a ROM, a Random Access Memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, and the like.

The foregoing is considered as illustrative of the embodiments of the disclosure and is not to be construed as limiting thereof, and any modifications, equivalents, improvements and the like made within the spirit and principle of the disclosure are intended to be included within the scope of the disclosure.

Claims

1. An internal battery of a mobile terminal, the internal battery comprising: naked electric core and electric core encapsulated layer, its characterized in that, built-in battery still includes:

the heat equalizing layer is arranged between the naked electric core and the electric core packaging layer, bonds the naked electric core and the electric core packaging layer, and equalizes heat of the heat emitted by the naked electric core, wherein the heat conductivity coefficient of the heat equalizing layer is larger than a preset threshold value;

2. The built-in battery of claim 1, wherein the material of the temperature reduction layer comprises: phase change materials, or thermoelectric materials;

the phase change material comprises at least one of silicon dioxide, aluminum oxide and calcium oxide.

3. The internal battery of claim 2, wherein the cell encapsulation layer and the cooling layer comprise an adhesive layer therebetween.

4. The internal battery according to claim 3, wherein the adhesive of the adhesive layer includes at least one of a rubber-based adhesive, a polyamide-based adhesive, a polypropylene-based adhesive, and a polyethylene-based adhesive.

5. The internal battery according to claim 3, wherein a total thickness of the cooling layer and the adhesive layer is between 0.2 mm and 2.0 mm, inclusive.

6. The internal battery according to any one of claims 1 to 5, wherein the thermal uniforming layer comprises a viscous coating;

the adhesive coating includes: any one of a graphene heat conduction layer, a graphite heat conduction layer, a silicon heat conduction layer and heat conduction gel.

7. The internal battery according to claim 6, wherein the thermal uniforming layer has a thickness between 0.5 mm and 2.0 mm, inclusive.

8. A mobile terminal characterized in that it comprises a built-in battery according to any one of claims 1 to 7.

9. The mobile terminal of claim 8, wherein the mobile terminal is a mobile terminal that supports a fast-charge mode;

and when the mobile terminal is in a quick charging mode for charging, the charging multiplying power is more than 1 coulomb.

10. The mobile terminal of claim 8, wherein the mobile terminal is a mobile terminal that supports a super fast charge mode;

and when the mobile terminal is in a super quick charging mode for charging, the charging multiplying power is more than 3 coulombs.