CN213753978U - Lithium battery secondary voltage protection circuit - Google Patents
Lithium battery secondary voltage protection circuit Download PDFInfo
- Publication number
- CN213753978U CN213753978U CN202022574832.8U CN202022574832U CN213753978U CN 213753978 U CN213753978 U CN 213753978U CN 202022574832 U CN202022574832 U CN 202022574832U CN 213753978 U CN213753978 U CN 213753978U
- Authority
- CN
- China
- Prior art keywords
- resistor
- triode
- mcu
- circuit
- pin
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
- Secondary Cells (AREA)
- Protection Of Static Devices (AREA)
Abstract
The utility model relates to a lithium cell secondary voltage protection circuit, including AFE, MCU, battery total voltage acquisition circuit and controllable three-terminal safety circuit, MCU is connected to AFE, and MCU connects battery total voltage acquisition circuit and controllable three-terminal safety circuit. The utility model discloses increase the circuit and a controllable three-terminal insurance of battery total voltage collection all the way on MCU, substitute the voltage protection chip, the cost is reduced, and circuit design is more simple.
Description
Technical Field
The utility model belongs to the lithium cell field relates to the overvoltage protection technique who relates to the lithium cell, especially a lithium cell secondary voltage protection circuit.
Background
At present, lithium batteries are widely applied, and have problems in use, the minimum unit voltage of the lithium batteries is lower, and in practical application, the lithium batteries are assembled by connecting the single batteries in parallel and in series to form a battery pack with larger capacity, higher voltage and larger current. The highest charging voltage of each battery is limited, and when the charging voltage is too high, the phenomenon of fire and explosion can occur, so that a battery protection board is placed in the battery pack to prevent a certain string of batteries from being too high. Because a single-string overvoltage protection circuit has the possibility of failure, secondary protection is needed in some occasions with higher safety level, at present, a secondary voltage protection chip is mostly placed in the market application mode to form double-path overvoltage acquisition, and when secondary overvoltage protection is triggered, the secondary protection chip actively fuses a main circuit fuse. However, this approach results in a complicated circuit and increased cost in the battery management system. To address this problem the present application proposes a circuit that detects secondary protection.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to overcome prior art's weak point, provide a circuit simple, with low costs lithium cell secondary voltage protection circuit.
The utility model provides a technical scheme that technical problem adopted is:
the utility model provides a lithium cell secondary voltage protection circuit, includes AFE, MCU, battery total voltage acquisition circuit and controllable three terminal safety circuit, and MCU is connected to AFE, and MCU connects battery total voltage acquisition circuit and controllable three terminal safety circuit.
The total battery voltage acquisition circuit comprises a resistor R14, a resistor R17, a resistor R13, a resistor R16 triode Q1 and a triode Q2, wherein the base of the triode Q2 is connected with the BATVEN pin of the MCU through a resistor R16, the collector of the triode Q2 is connected with the base of the triode Q1 through a resistor R13, the emitter of the triode Q1 is connected with the total battery voltage VPACK, the collector of the triode Q1 is connected with one end of the resistor R14, the other end of the resistor R14 is connected with one end of the resistor R17 and the BATV pin of the MCU, the other end of the resistor R17 is connected with the emitter of the triode Q2 and the capacitor C10 and grounded, and the capacitor C10 is connected with the BATV pin of the MCU.
The controllable three-terminal safety circuit comprises a resistor R1, a resistor R2, a triode Q3 and a fuse F1, wherein a first pin of the fuse F1 is connected with a total positive B + of the battery, a second pin of the fuse F1 is connected with a total positive P + of the output of the battery pack, a third pin of the fuse F1 is connected with a collector of the triode Q3, an emitter of the triode Q3 is grounded, a base of the triode Q3 is connected with the resistor R2 and the resistor R1, the resistor R2 is grounded, and the resistor R1 is connected with an EVPEN pin of the MCU.
The model of the AFE is SH79F 367309.
Moreover, the model of the MCU is GD32E 103.
The utility model has the advantages that:
the utility model discloses increase the circuit and a controllable three-terminal insurance of battery total voltage collection all the way on MCU, substitute the voltage protection chip, the cost is reduced, and circuit design is more simple.
Drawings
FIG. 1 is a block diagram of the present protection circuit;
FIG. 2 is a circuit diagram of a total voltage acquisition circuit of the battery;
fig. 3 is a diagram of a controllable triac circuit.
Detailed Description
The present invention will be described in further detail with reference to specific examples, which are provided for illustrative purposes only, and are not intended to be limiting, and the scope of the present invention should not be limited thereby.
A secondary voltage protection circuit of a lithium battery comprises an analog front end AFE (automatic front end) capable of collecting voltage of each string of batteries, an MCU (microprogrammed control unit) capable of communicating with the AFE to process data and a charging switch. And the MCU is connected with the battery total voltage acquisition circuit and the controllable three-terminal safety circuit.
The total battery voltage acquisition circuit comprises a resistor R14, a resistor R17, a resistor R13, a resistor R16 triode Q1 and a triode Q2, wherein the base electrode of the triode Q2 is connected with a BATVEN pin of the MCU through a resistor R16, the collector electrode of the triode Q2 is connected with the base electrode of the triode Q1 through a resistor R13, the emitter electrode of the triode Q1 is connected with the total battery voltage VPACK, the collector electrode of the triode Q1 is connected with one end of the resistor R14, the other end of the resistor R14 is connected with one end of the resistor R17 and the BATV pin of the MCU, the other end of the resistor R17 is connected with the emitter electrode of the triode Q2 and a capacitor C10 which are grounded, and a capacitor C10 is connected with the BATV pin of the MCU.
The controllable three-terminal safety circuit comprises a resistor R1, a resistor R2, a triode Q3 and a fuse F1, wherein a first pin of the fuse F1 is connected with a total positive B + of a battery, a second pin of the fuse F1 is connected with a total positive P + of the output of a battery pack, a third pin of the fuse F1 is connected with a collector of the triode Q3, an emitter of the triode Q3 is grounded, a base of the triode Q3 is connected with the resistor R2 and the resistor R1, the resistor R2 is grounded, and the resistor R1 is connected with an EVPEN pin of the MCU.
The model of the AFE is SH79F 367309. The model of the MCU is GD32E 103.
The utility model discloses a theory of operation does:
the overvoltage protection of the AFE belongs to primary voltage protection, the overvoltage protection controlled by the MCU belongs to secondary voltage protection, and the secondary protection voltage is higher than the primary protection voltage. Normally, the AFE can protect the cells from overvoltage, but when the AFE fails, the AFE will not control the main circuit if the charging switch is tripped. The sum of the total voltage collected by the MCU and the sum of the single-string voltages collected by the AFE are mutually compared, and if one voltage fails or the battery triggers the secondary protection voltage, the MCU controls the three-terminal fuse to be fused to stop charging and discharging.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, many modifications and improvements can be made without departing from the spirit of the present invention, and these modifications and improvements are all within the protection scope of the present invention.
Claims (5)
1. A lithium battery secondary voltage protection circuit is characterized in that: the device comprises an AFE (automatic Circuit), an MCU (micro control Unit), a battery total voltage acquisition circuit and a controllable three-terminal safety circuit, wherein the AFE is connected with the MCU, and the MCU is connected with the battery total voltage acquisition circuit and the controllable three-terminal safety circuit.
2. The lithium battery secondary voltage protection circuit of claim 1, wherein: the total battery voltage acquisition circuit comprises a resistor R14, a resistor R17, a resistor R13, a resistor R16 triode Q1 and a triode Q2, wherein the base electrode of the triode Q2 is connected with a BATVEN pin of the MCU through a resistor R16, the collector electrode of the triode Q2 is connected with the base electrode of the triode Q1 through a resistor R13, the emitter electrode of the triode Q1 is connected with the total battery voltage VPACK, the collector electrode of the triode Q1 is connected with one end of the resistor R14, the other end of the resistor R14 is connected with one end of the resistor R17 and the BATV pin of the MCU, the other end of the resistor R17 is connected with the emitter electrode of the triode Q2 and a capacitor C10 which are grounded, and a capacitor C10 is connected with the BATV pin of the MCU.
3. The lithium battery secondary voltage protection circuit of claim 1, wherein: the controllable three-terminal safety circuit comprises a resistor R1, a resistor R2, a triode Q3 and a fuse F1, wherein a first pin of the fuse F1 is connected with a total positive B + of a battery, a second pin of the fuse F1 is connected with a total positive P + of the output of a battery pack, a third pin of the fuse F1 is connected with a collector of the triode Q3, an emitter of the triode Q3 is grounded, a base of the triode Q3 is connected with the resistor R2 and the resistor R1, the resistor R2 is grounded, and the resistor R1 is connected with an EVPEN pin of the MCU.
4. The lithium battery secondary voltage protection circuit of claim 1, wherein: the model of the AFE is SH79F 367309.
5. The lithium battery secondary voltage protection circuit of claim 1, wherein: the model of the MCU is GD32E 103.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022574832.8U CN213753978U (en) | 2020-11-10 | 2020-11-10 | Lithium battery secondary voltage protection circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022574832.8U CN213753978U (en) | 2020-11-10 | 2020-11-10 | Lithium battery secondary voltage protection circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN213753978U true CN213753978U (en) | 2021-07-20 |
Family
ID=76821574
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202022574832.8U Active CN213753978U (en) | 2020-11-10 | 2020-11-10 | Lithium battery secondary voltage protection circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN213753978U (en) |
-
2020
- 2020-11-10 CN CN202022574832.8U patent/CN213753978U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN209329677U (en) | Overheating protection circuit, electronic cigarette and electronic equipment | |
| CN209389733U (en) | Lithium battery protection board | |
| WO2017148123A1 (en) | Battery protecting device and power assembly | |
| CN205489484U (en) | Protection of secondary battery and power supply module | |
| CN110829585A (en) | Double-circuit power supply device and power supply system | |
| CN2922241Y (en) | Vehicle lithium ion storage cell equalizing protecting circuit | |
| CN205489483U (en) | Protection of secondary battery and power supply module | |
| CN213753978U (en) | Lithium battery secondary voltage protection circuit | |
| CN106356987A (en) | RTC (real time clock) circuit | |
| CN205195249U (en) | Digit BMS protection shield with data storage function | |
| CN207743753U (en) | A kind of self-starting device of lithium ion battery applications Large UPS power supply | |
| CN112838647B (en) | Lithium ion battery circuit with multiple protection functions | |
| CN214755484U (en) | Pre-charging circuit based on PTC | |
| CN211046468U (en) | Lithium battery short-circuit protection circuit | |
| CN210780162U (en) | Charger detection device | |
| CN205016998U (en) | Battery protection chip and battery | |
| CN210380315U (en) | Low-voltage battery charging protection circuit | |
| CN108736559A (en) | A kind of solar storage battery charging-discharging controller based on memristor | |
| CN206894318U (en) | A kind of solar storage battery charging-discharging controller based on memristor | |
| CN111654080A (en) | Be used for battery package overcharge overdischarge duplicate protection circuit | |
| CN107134756A (en) | Battery protecting apparatus and power supply module | |
| CN210297333U (en) | Combined capacitor module circuit with charging current control | |
| CN210469355U (en) | LoRa module power supply circuit of undercurrent power supply | |
| CN212588103U (en) | Be used for battery package overcharge overdischarge duplicate protection circuit | |
| CN104124670B (en) | A kind of dual-protection circuit of lithium battery |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |