CN213585208U

CN213585208U - Charging-discharging and display control circuit of lithium ion battery

Info

Publication number: CN213585208U
Application number: CN202022273322.7U
Authority: CN
Inventors: 刘辉; 胡蒙杰; 邬嘉男
Original assignee: Ningbo Nengxin Electronics Co Ltd
Current assignee: Ningbo Nengxin Electronics Co Ltd
Priority date: 2020-10-13
Filing date: 2020-10-13
Publication date: 2021-06-29
Anticipated expiration: 2030-10-13

Abstract

The utility model discloses a lithium ion battery charge-discharge and display control circuit, including two sections lithium ion battery, mode identification converting circuit, charging voltage identification circuit, battery abnormity indicating circuit, prevent the mistake charging circuit, overdischarge circuit and display control circuit, wherein two sections lithium ion battery pass through the mode identification converting circuit and discern whether for the charging mode, two sections lithium ion battery are parallelly connected and independent separately during charging, two sections lithium ion battery series connection power supplies during discharging, adopt a CPU who takes AD collection function to control. The utility model provides a lithium ion charge-discharge and display control circuit possesses that the battery overcharges, overflows, overdischarging and battery unusual (open a way, short circuit and reversal) protection and charging input voltage discernment protection let hold the electrical product on hand safer to have low cost, safer, more convenient, advantages such as long service life.

Description

Charging-discharging and display control circuit of lithium ion battery

Technical Field

The utility model belongs to the technical field of the electronic circuit, especially, relate to a lithium ion battery charge-discharge and display control circuit.

Background

A lithium ion battery is a secondary battery (rechargeable battery) that mainly operates by movement of lithium ions between a positive electrode and a negative electrode. During the charge and discharge process, lithium ions are intercalated and deintercalated between the two electrodes: during charging, lithium ions are extracted from the positive electrode and are inserted into the negative electrode through the electrolyte, and the negative electrode is in a lithium-rich state; the opposite is true during discharge.

The lithium ion battery charging control is divided into two stages, the first stage is constant current charging, and when the battery voltage is lower than 4.2V, the charger charges with constant current. The second stage is the constant voltage charging stage, when the battery voltage reaches 4.2V, because lithium ion battery characteristic, if the voltage is high again, will damage, the charger can fix the voltage at 4.2V, and charging current can reduce gradually, when the electric current reduces to a definite value (generally when 1/10 sets up the electric current), cuts off charging circuit, and the completion of charging pilot lamp is bright, the completion of charging.

The lithium ion battery is permanently damaged by over-charging and discharging of the positive and negative electrodes. Over-discharge causes the collapse of the carbon sheet layer structure of the cathode, and the collapse can cause that lithium ions can not be inserted in the charging process; the overcharge causes excessive lithium ions to be inserted into the carbon structure of the negative electrode, so that part of the lithium ions cannot be released any more.

When the lithium ion battery is charged and discharged, multiple protections are required: short-circuit protection, overcurrent protection, overvoltage protection, reverse battery connection protection and the like. For this purpose, the protection device monitors the battery voltage and, when it reaches the battery overcharge voltage, activates the overcharge protection function and stops charging. Over-discharge protection: in order to prevent an overdischarge state of the lithium ion battery, when the lithium ion battery voltage is lower than its overdischarge voltage detection point, an overdischarge protection is activated, the discharge is terminated, and the battery is maintained in a standby mode of low quiescent current. Overcurrent and short-circuit protection: when the discharge current of the lithium ion battery is overlarge or a short circuit condition is generated, the protection device activates an overcurrent protection function.

However, in the existing charge and discharge detection circuit, the charge and discharge detection function and the charge and discharge indicator function are usually designed separately, that is, the charge detection function is realized by one identification chip and a corresponding peripheral circuit, the charge indicator function is realized by another chip and a corresponding peripheral circuit, the discharge detection function is realized by one identification chip and a corresponding peripheral circuit, and the discharge indicator function is realized by another chip and a corresponding peripheral circuit, so that the charge and discharge circuit is complicated, and the design of dividing into four groups of circuits increases additional chips, which causes the increase of circuit cost.

SUMMERY OF THE UTILITY MODEL

In view of the above situation, the utility model provides a lithium ion battery charge-discharge and display control circuit, this lithium ion charge-discharge and display control circuit possess the battery overcharge, overflow, overdischarge and battery unusual (open a way, short circuit and reversal) protection and charge input voltage discernment protection, let the electrical product of holding on hand safer to have advantages such as low cost, safer, more convenient, long service life.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a lithium ion battery charging and discharging and display control circuit comprises two lithium ion batteries, a mode identification conversion circuit, a charging voltage identification circuit, a battery abnormity indication circuit, an anti-error charging circuit, an over-discharging circuit and a display control circuit, wherein the two lithium ion batteries identify whether the charging mode is adopted or not through the mode identification conversion circuit, the two lithium ion batteries are connected in parallel and are independent respectively during charging, the two lithium ion batteries are connected in series for power supply during discharging, and a CPU with an AD acquisition function is adopted for control;

the charging voltage identification circuit can detect the voltage of the lithium ion battery and feed back the voltage to the battery abnormality indication circuit, the anti-mis-charging circuit and the display control circuit according to different voltages of the lithium ion battery;

the over-discharge circuit provides LED load over-current protection and battery over-discharge protection by using an MCU control technology when the lithium ion battery is in discharge.

The utility model discloses further preferred scheme: the lithium ion battery is a 18650 battery.

The utility model discloses further preferred scheme: the charging voltage identification circuit comprises a charging circuit and a lithium ion protection circuit.

Compared with the prior art, the utility model has the advantages of:

1) the utility model provides a lithium ion battery charge-discharge and display control circuit adopts the CPU with AD acquisition function to control the charge-discharge of the lithium ion battery, can simplify the charge-discharge circuit, thereby reducing the circuit cost;

2) the utility model provides a lithium ion battery charge-discharge and display control circuit possess the battery simultaneously and cross charge, overflow, cross discharge and battery unusual (open a way, short circuit and reversal) protection and charge input voltage discernment protection, let and hold the electrical product on hand safer to have low cost, safer, more convenient, advantages such as long service life.

Drawings

The present invention will be described in further detail below with reference to the drawings and preferred embodiments, but those skilled in the art will appreciate that the drawings are only drawn for the purpose of explaining the preferred embodiments, and therefore should not be taken as limiting the scope of the present invention. Furthermore, unless specifically stated otherwise, the drawings are merely schematic representations based on conceptual representations of elements or structures depicted and may contain exaggerated displays and are not necessarily drawn to scale.

Fig. 1 is the overall structure diagram of the lithium ion battery charging/discharging and display control circuit of the present invention.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings.

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the invention.

As shown in fig. 1: the utility model provides a lithium ion battery charge-discharge and display control circuit, includes two sections lithium ion battery, mode identification converting circuit, charging voltage identification circuit, battery abnormity indicating circuit, prevents that the circuit that charges by mistake, overdischarge circuit and display control circuit, wherein two sections lithium ion battery pass through the mode identification converting circuit and discern whether to be the mode of charging, and two sections lithium ion battery are parallelly connected and independent respectively during charging, and two sections lithium ion battery series connection power supply during discharging adopts a CPU who takes AD collection function to control.

The charging voltage identification circuit can detect the voltage of the lithium ion battery and feed back the voltage to the battery abnormality indication circuit, the anti-mis-charging circuit and the display control circuit according to different voltages of the lithium ion battery. In addition, the charging voltage identification circuit comprises a charging circuit and a lithium ion protection circuit.

In the embodiment of the utility model provides an, lithium ion battery is 18650 batteries.

The embodiment of the utility model provides an in, the control process of charging is 18650 batteries of a power management chip control when charging, every battery department all has a lithium battery protection chip protection simultaneously, and only discern the 5V charger, judge by the CPU who takes AD acquisition function, trickle according to the standard, the constant current, the constant voltage syllogic mode of charging charges the battery, effectively guarantee safety and battery life charge, and ensure that the battery reaches the full charge amount, and there is corresponding electric quantity pilot lamp drive (the ruddiness of charging instruction, be full of and change green light instruction), single maximum charging current can reach 1A, thereby possess battery unusual (open a way, short circuit and reversal connection) protection and the input reversal protection of charging.

The embodiment of the utility model provides an in, discharge control process is two 18650 batteries when discharging and establishes ties, possesses that the LED load overflows protection and battery and overdischarge (5.2V) protection. The maximum working current of the LED load is 3.5A, PWM curve discharge is adopted, the PWM frequency is 20KHZ, and the static power consumption of the whole machine is less than 80 uA.

Through the description, the utility model discloses a lithium ion battery charge-discharge and display control circuit possess the battery simultaneously and cross charge, overflow, cross discharge and battery unusual (open a way, short circuit and reversal) protection and charge input voltage discernment protection, let and hold the electrical product on hand safer to have low cost, safer, more convenient, advantages such as long service life.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may include, for example, a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The above is to the utility model discloses going on the detailed introduction, having used specific individual example to right in this paper the utility model discloses a principle and implementation mode have been elucidated, and the explanation of above embodiment only is used for helping understanding the utility model discloses and core thought. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, the present invention can be further modified and modified, and such modifications and modifications also fall within the protection scope of the appended claims.

Claims

1. The utility model provides a lithium ion battery charge-discharge and display control circuit, includes two sections lithium ion battery, mode identification converting circuit, charging voltage identification circuit, battery abnormity indicating circuit, prevents that the circuit that charges by mistake, overdischarge circuit and display control circuit, its characterized in that: the two lithium ion batteries are identified whether to be in a charging mode or not through the mode identification conversion circuit, the two lithium ion batteries are connected in parallel and are independent respectively during charging, the two lithium ion batteries are connected in series for power supply during discharging, and a CPU with an AD acquisition function is adopted for control; the charging voltage identification circuit can detect the voltage of the lithium ion battery and feed back the voltage to the battery abnormality indication circuit, the anti-mis-charging circuit and the display control circuit according to different voltages of the lithium ion battery; the over-discharge circuit provides LED load over-current protection and battery over-discharge protection by using an MCU control technology when the lithium ion battery is in discharge.

2. The lithium ion battery charging/discharging and display control circuit according to claim 1, wherein: the lithium ion battery is a 18650 battery.

3. The lithium ion battery charging/discharging and display control circuit according to claim 1, wherein: the charging voltage identification circuit comprises a charging circuit and a lithium ion protection circuit.