A lithium battery charging circuit control method and system

Abstract

The present invention relates to a lithium battery charging circuit control method, comprising the following steps: S1, the charging circuit charges the lithium battery, and at the same time obtains the current charging process of the lithium battery, the charging process comprising: trickle charging, constant current charging, and constant voltage charging; S2, if the current charging process of the lithium battery is constant current charging, then obtain the vibration information of the lithium battery; S3, when the lithium battery is vibrated, reduce the charging current or stop charging completely; S4, after the vibration of the lithium battery stops, the charging process returns to constant current charging. The present invention can automatically reduce the charging current or stop charging completely when the battery is vibrated, and can effectively protect the battery from the smallest possible charging current under the condition of vibration, thereby effectively reducing the generation of dendrites in the battery due to vibration during the charging process, and further extending the battery life.

Description

Technical Field

[0001] This invention relates to the field of lithium battery charging protection, specifically to a lithium battery charging circuit control method. Background Art

[0002] Lithium-ion batteries are a type of battery that uses lithium metal or lithium alloy as the negative electrode material and a non-aqueous electrolyte solution. Lithium-ion batteries have no memory effect, so they can be charged and discharged at any time.

[0003] The charging process of lithium batteries generally includes three stages: trickle charging, constant current charging, and constant voltage charging. Trickle charging is used to pre-charge (recovery charging) fully discharged battery cells. Trickle charging is used when the battery voltage is below approximately 3V, and the trickle charging current is one-tenth of the constant current charging current, i.e., 0.1C. When the battery voltage rises above the trickle charging threshold, the charging current is increased to initiate constant current charging. The constant current charging current is between 0.2C and 1.0C. The battery voltage gradually increases during constant current charging; this voltage is typically set at 3.0-4.2V for a single cell. When the battery voltage reaches 4.2V, constant current charging ends, and the constant voltage charging stage begins. The current decreases gradually from its maximum value as the charging process continues, depending on the cell's saturation level. Charging is considered terminated when the current decreases to 0.01C.

[0004] With advancements in battery technology and changing user habits, fast charging technology is increasingly being incorporated into various products. Fast charging offers rapid charging speeds, especially during the constant current charging phase, where the charging current can often reach 1-3C or even higher. During high-current charging, the reduction of lithium ions forms dendritic lithium metal, or lithium dendrites. Lithium dendrite growth is one of the fundamental issues affecting the safety and stability of lithium-ion batteries. Vibration during charging can accelerate dendrite formation in lithium batteries.

[0005] The purpose of this invention is to design a lithium battery charging circuit control method to address the problems existing in the prior art. Summary of the Invention

[0006] To address the problems existing in the prior art, the present invention provides a lithium battery charging circuit control method that can effectively solve the problems existing in the prior art.

[0007] The technical solution of the present invention is:

[0008] A lithium battery charging circuit control method includes the following steps:

[0009] S1, the charging circuit charges the lithium battery and simultaneously acquires the current charging process of the lithium battery, the charging process including: trickle charging, constant current charging, and constant voltage charging.

[0010] S2, If the current charging process of the lithium battery is constant current charging, then obtain the vibration information of the lithium battery;

[0011] S3: When the lithium battery is subjected to vibration, reduce the charging current or stop charging completely;

[0012] S4, after the vibration experienced by the lithium battery stops, the charging process resumes constant current charging.

[0013] Furthermore, in step S2, the vibration information includes an acceleration value a.

[0014] Furthermore, for the lithium battery, the mass m and the gravitational acceleration g, if m*a is greater than m*g*30%, then the battery is determined to be subjected to vibration.

[0015] Furthermore, in step S3, reducing the charging current or completely stopping charging specifically involves:

[0016] S3.1 When m*a is greater than m*g*50%, the charging circuit is controlled to completely stop charging;

[0017] S3.2 When m*a is greater than m*g*30% and less than m*g*50%, control the charging circuit to reduce the charging current.

[0018] Furthermore, regarding the battery capacity C, in step S3.2, the charging current is less than 0.1C.

[0019] Furthermore, the battery capacity C, and the charging current of the constant current charging are greater than 1C.

[0020] Furthermore, a lithium battery charging circuit control system is provided, comprising:

[0021] The charging circuit charges the lithium battery;

[0022] A current and voltage acquisition module acquires the current charging status, which includes current and voltage.

[0023] An accelerometer detects vibrations in the lithium battery.

[0024] The MCU receives signals from the current and voltage acquisition module and the vibration sensor, and determines the charging process, which includes trickle charging, constant current charging, and constant voltage charging. When the lithium battery is subjected to vibration and the charging process is constant current charging: the MCU controls the charging circuit to reduce the charging current or completely stop charging; after the vibration of the lithium battery stops, the MCU controls the charging circuit to resume the charging process of constant current charging.

[0025] The vibration sensor is an acceleration sensor.

[0026] The vibration sensor is located on one end of the terminal device near the lithium battery.

[0027] Alternatively, the vibration sensor may be positioned at one end of the power line near the lithium battery.

[0028] Therefore, the present invention provides the following effects and / or advantages:

[0029] 1. This invention can automatically reduce the charging current or completely stop charging when the battery is subjected to vibration. It can effectively protect the battery by minimizing the charging current under vibration, thereby effectively reducing the formation of dendrites in the battery due to vibration during charging and further extending the battery life.

[0030] 2. This invention uses an accelerometer and battery mass information to effectively determine the vibration force on the battery. By comparing the vibration force with the battery weight, it stops charging for large vibration forces (greater than m*g*50%) or reduces the charging current for small vibration forces (greater than m*g*30% and less than m*g*50%).

[0031] 3. This invention only activates the control method during trickle charging. During trickle charging and constant voltage charging, the battery charging current is small, the battery itself generates fewer dendrites, and the impact of vibration on the generation of dendrites in the battery itself is small or even negligible.

[0032] 4. The system that implements this control method can be integrated into the end of the charging cable near the device containing the lithium battery, or integrated into the interior of the device containing the lithium battery, which can effectively implement this control method.

[0033] It should be understood that the above summary and the following detailed description of the invention are exemplary and explanatory, and are intended to provide further explanation of the invention as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a functional diagram of Example 2.

[0035] Figure 2 This is a schematic diagram of Example 3.

[0036] Figure 3 This is a schematic diagram of Example 4. Detailed Implementation

[0037] To facilitate understanding by those skilled in the art, the structure of the present invention will now be described in further detail with reference to the accompanying drawings:

[0038] Example 1

[0039] A lithium battery charging circuit control method includes the following steps:

[0040] S1, the charging circuit charges the lithium battery and simultaneously acquires the current charging process of the lithium battery, the charging process including: trickle charging, constant current charging, and constant voltage charging.

[0041] S2, If the current charging process of the lithium battery is constant current charging, then obtain the vibration information of the lithium battery, which includes the acceleration value a.

[0042] S3: When the lithium battery is subjected to vibration, reduce the charging current or stop charging completely;

[0043] Given the mass m of the lithium battery and the gravitational acceleration g, if m*a is greater than m*g*30%, the battery is considered to be subjected to vibration.

[0044] S3.1 When m*a is greater than m*g*50%, the charging circuit is controlled to completely stop charging;

[0045] S3.2 When m*a is greater than m*g*30% and less than m*g*50%, the charging circuit is controlled to reduce the charging current, and the battery capacity C and charging current are less than 0.1C.

[0046] S4, after the vibration of the lithium battery stops, the charging process resumes constant current charging, the battery capacity is C, and the charging current of the constant current charging is greater than 1C.

[0047] Example 2

[0048] refer to Figure 1 ,

[0049] A lithium battery charging circuit control system, comprising:

[0050] The charging circuit charges the lithium battery;

[0051] A current and voltage acquisition module acquires the current charging status, which includes current and voltage.

[0052] An accelerometer detects vibrations in the lithium battery.

[0053] The MCU receives signals from the current and voltage acquisition module and the vibration sensor, and determines the charging process, which includes trickle charging, constant current charging, and constant voltage charging. When the lithium battery is subjected to vibration and the charging process is constant current charging: the MCU controls the charging circuit to reduce the charging current or completely stop charging; after the vibration of the lithium battery stops, the MCU controls the charging circuit to resume the charging process of constant current charging.

[0054] The vibration sensor is an acceleration sensor.

[0055] Example 3

[0056] This embodiment is largely the same as Embodiment Two. Further, refer to... Figure 2 The vibration sensor 1 is located on the terminal device 3 near the end of the lithium battery 2.

[0057] Example 4

[0058] This embodiment is largely the same as Embodiment Two. Further, refer to... Figure 3 The vibration sensor 1 is located at one end of the power line 3 near the lithium battery 2.

[0059] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should be included in the scope of the present invention.

Claims

1. A lithium battery charging circuit control method, characterized in that: The following steps are involved: S1, the charging circuit charges the lithium battery and obtains the current charging process of the lithium battery, wherein the charging process includes: trickle charging, constant current charging, and constant voltage charging; S2, if the current charging process of the lithium battery is constant current charging, obtain the vibration information of the lithium battery; S3, when the lithium battery is subjected to vibration, the charging current is reduced or charging is stopped completely; S4, after the vibration of the lithium battery stops, the charging process is restored to constant current charging; in step S2, the vibration information includes the acceleration value a; the mass m of the lithium battery, the gravity acceleration g, when m*a is greater than m*g*30%, it is determined that the battery is vibrated; In step S3, reducing the charging current or completely stopping charging is specifically as follows: S3.1 When m*a is greater than m*g*50%, the charging circuit is controlled to completely stop charging; S3.2 When m*a is greater than m*g*30% and less than m*g*50%, the charging circuit is controlled to reduce the charging current.

2. A lithium battery charging circuit control method according to claim 1, characterized in that: The battery capacity is C. In step S3.2, the charging current is less than 0.1C.

3. A lithium battery charging circuit control method according to claim 1, characterized in that: The battery capacity is C, and the charging current of the constant current charging is greater than 1C.

4. A lithium battery charging circuit control system applied to a lithium battery charging circuit control method according to any one of claims 1 to 3, characterized in that: Include: Charging circuit, charging the lithium battery; A current and voltage acquisition module is used to acquire the current charging state, wherein the charging state includes current and voltage; Acceleration sensor, to detect the vibration of lithium battery; MCU receives signals from the current and voltage acquisition module and the vibration sensor, and determines the charging process, which includes trickle charging, constant current charging, and constant voltage charging. When the lithium battery is vibrated and the charging process is constant current charging: the MCU controls the charging circuit to reduce the charging current or completely stop charging; after the vibration of the lithium battery stops, the MCU controls the charging circuit to resume the charging process to constant current charging.

5. A lithium battery charging circuit control system according to claim 4, characterized in that: The vibration sensor is an acceleration sensor.

6. A lithium battery charging circuit control system according to claim 4, characterized in that: The vibration sensor is arranged on one end of the terminal device close to the lithium battery.

7. A lithium battery charging circuit control system according to claim 4, characterized in that: The vibration sensor is arranged at one end of the power line close to the lithium battery.

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