阅读说明：本技术 一种电池组短路保护电路装置及方法 (Battery pack short-circuit protection circuit device and method ) 是由 姚斌 施璐 尹志斌 胡艳子 于 2019-12-26 设计创作，主要内容包括：本发明实施例公开了一种电池组短路保护电路装置及方法,该装置包括电池组、检流电阻、放电场效应管、充电场效应管、短路保护场效应管、限流电阻、控制模块和充电单元；电池组、检流电阻、放电电场效应管、充电场效应管和充电单元依次串联,放电场效应管两端并联有短路场效应管和限流电阻,控制模块分别与检流电阻电、放电场效应管、充电场效应管和短路保护场效应管电连接,输出使能信号使充电场效应管闭合和短路保护场效应管闭合,并在预设时间内输出使能信号使放电场效应管闭合,在通过检流电阻检测到回路出现短路时输出使能信号以使放电场效应管关断。实现了短路保护电路简单可靠、成本低,不存在短路保护次数限制、电流电压等级不受限制等效果。(The embodiment of the invention discloses a battery pack short-circuit protection circuit device and a method, wherein the device comprises a battery pack, a current detection resistor, a discharge field-effect tube, a charge field-effect tube, a short-circuit protection field-effect tube, a current limiting resistor, a control module and a charging unit; the battery pack, the current detection resistor, the discharge electric field effect tube, the charge field effect tube and the charge unit are sequentially connected in series, a short circuit field effect tube and a current limiting resistor are connected in parallel at two ends of the discharge field effect tube, the control module is respectively electrically connected with the current detection resistor, the discharge field effect tube, the charge field effect tube and the short circuit protection field effect tube, an enabling signal is output to enable the charge field effect tube to be closed and the short circuit protection field effect tube to be closed, the enabling signal is output to enable the discharge field effect tube to be closed within preset time, and the enabling signal is output to enable the discharge field effect tube to be turned off when the short circuit of a loop is. The short-circuit protection circuit is simple and reliable, low in cost, free of short-circuit protection frequency limitation, free of current and voltage class limitation and the like.)

1. A battery pack short-circuit protection circuit device is characterized by comprising a battery pack, a current detection resistor, a discharge field effect transistor, a charge field effect transistor, a short-circuit protection field effect transistor, a current limiting resistor, a control module and a charging unit;

the positive electrode of the battery pack is connected with the input end of the charging unit; the negative electrode of the battery pack is connected with the first end of the current detection resistor, the second end of the current detection resistor is respectively connected with the drain of the discharge field-effect tube and the drain of the short-circuit protection field-effect tube, the source of the short-circuit protection field-effect tube is connected with the first end of the current limiting resistor, the source of the discharge field-effect tube and the second end of the current limiting resistor are respectively connected with the drain of the charge field-effect tube, and the source of the charge field-effect tube is connected with the output end of the charging unit;

the first input end of the control module is connected with the second end of the current detection resistor, the control module comprises a first enabling end, a second enabling end and a third enabling end, the first enabling end is electrically connected with the grid of the discharge field effect transistor, the second enabling end is electrically connected with the grid of the charge field effect transistor, and the third enabling end is electrically connected with the grid of the short-circuit protection field effect transistor;

the control module is used for outputting a second enabling signal to close the charging field effect transistor, outputting a third enabling signal to close the short-circuit protection field effect transistor, outputting a first enabling signal to the discharging field effect transistor within a preset time to close the discharging field effect transistor, and outputting a first enabling signal to turn off the discharging field effect transistor when the short circuit of the loop is detected through the current detection resistor.

2. The battery short-circuit protection circuit device according to claim 1, wherein the control module is further configured to output a third enable signal within a preset delay time after the discharging fet is turned off to turn off the short-circuit protection fet.

3. The battery pack short-circuit protection circuit device according to claim 1, wherein the control module includes a comparator and a control unit; the first input end of the comparator is electrically connected with the reference voltage end, the second input end of the comparator is electrically connected with the second end of the current detection resistor, and the output end of the comparator is electrically connected with the control unit and used for comparing the output voltage of the second end of the current detection resistor with the reference voltage and outputting the comparison result to the control unit; and the control unit is used for controlling the switching-off and the switching-on of the discharge field effect transistor according to the comparison result.

4. The battery pack short-circuit protection circuit device according to claim 1, wherein the charging unit comprises a load and a battery pack charging power supply, an input terminal of the load and an input terminal of the battery pack charging power supply are respectively connected to the positive electrode of the battery pack, and an output terminal of the load and an output terminal of the battery pack charging power supply are respectively connected to the source stage of the charging fet.

5. The battery pack short-circuit protection circuit device according to claim 1, wherein the current limiting resistor is a thermistor.

6. The battery pack short-circuit protection circuit device according to claim 1, wherein the discharge fet, the charge fet, and the short-circuit protection fet are P-type fets.

7. The battery pack short-circuit protection circuit device according to claim 1, wherein the battery pack is formed by connecting a plurality of battery cells in series.

8. A battery pack short-circuit protection circuit method is characterized by being suitable for a battery pack short-circuit protection circuit device, wherein the battery pack short-circuit protection circuit device comprises a battery pack, a current detection resistor, a discharge field effect transistor, a charge field effect transistor, a short-circuit protection field effect transistor, a current limiting resistor, a charge unit and a control module;

the positive electrode of the battery pack is connected with the input end of the charging unit; the negative electrode of the battery pack is connected with the first end of the current detection resistor, the second end of the current detection resistor is respectively connected with the drain of the discharge field-effect tube and the drain of the short-circuit protection field-effect tube, the source of the short-circuit protection field-effect tube is connected with the first end of the current limiting resistor, the source of the discharge field-effect tube and the second end of the current limiting resistor are respectively connected with the drain of the charge field-effect tube, and the source of the charge field-effect tube is connected with the output end of the charging unit;

the first input end of the control module is connected with the second end of the current detection resistor, the control module comprises a first enabling end, a second enabling end and a third enabling end, the first enabling end is electrically connected with the grid of the discharge field effect transistor, the second enabling end is electrically connected with the grid of the charge field effect transistor, and the third enabling end is electrically connected with the grid of the short-circuit protection field effect transistor;

the battery pack short-circuit protection circuit method comprises the following steps:

after the power is on, outputting a second enabling signal to close the charging field effect transistor, outputting a third enabling signal to close the short-circuit protection field effect transistor, and outputting a first enabling signal within a preset time to close the short-circuit protection field effect transistor;

when the short circuit of the loop is detected through the current detection resistor, a first enabling signal is output to enable the discharging field effect transistor to be turned off.

9. The battery short-circuit protection circuit method according to claim 7, wherein after outputting a first enable signal to turn off the discharge field-effect transistor when the short circuit of the circuit is detected by the current detection resistor, the method further comprises:

and outputting a third enabling signal within a preset time delay time to turn off the short-circuit protection field effect transistor.

10. The battery short-circuit protection circuit method according to claim 7, further comprising performing initialization configuration and self-test after power-up.

Technical Field

The embodiment of the invention relates to a battery pack short-circuit protection technology, in particular to a battery pack short-circuit protection circuit device and a battery pack short-circuit protection method.

Background

Along with the progress of science and technology, the integration of equipment in various industries is higher and higher, the application of lithium battery packs is wider and wider, the lithium battery packs are mainly applied to various fields such as base station backup batteries, portable energy storage batteries and household energy storage, the battery application in different industries has safe operation and long-term reliability, serious faults and even thermal runaway cannot occur during working, the requirements of fire explosion and the like cannot occur, and particularly the lithium battery packs have strong requirements on short-circuit protection.

The short-circuit protection circuit is an important component in protecting the short circuit of the lithium battery. In the prior art, when an external circuit is short-circuited, the withstand voltage of a discharge field effect transistor connected in series in a lithium battery short-circuit protection circuit is improved, so that the cost is greatly increased, and the thermal management design of a battery pack is not facilitated; in addition, although the discharge field effect transistor is connected in parallel with the transient diode, the absorption capacity and the protection frequency of the discharge field effect transistor are limited, the cost is increased, and the short-circuit protection function cannot be realized completely and reliably.

Disclosure of Invention

The embodiment of the invention provides a device and a method for a battery short-circuit protection circuit, which aim to realize the effects of simple and reliable short-circuit protection circuit, low cost, no short-circuit protection frequency limitation and the like.

In a first aspect, an embodiment of the present invention provides a battery pack short-circuit protection circuit apparatus, where the apparatus includes a battery pack, a current detection resistor, a discharge field-effect transistor, a charge field-effect transistor, a short-circuit protection field-effect transistor, a current limiting resistor, a control module, and a charging unit.

The positive electrode of the battery pack is connected with the input end of the charging unit; the negative electrode of the battery pack is connected with the first end of the current detection resistor, the second end of the current detection resistor is respectively connected with the drain of the discharge field effect transistor and the drain of the short-circuit protection field effect transistor, the source of the short-circuit protection field effect transistor is connected with the first end of the current limiting resistor, the source of the discharge field effect transistor and the second end of the current limiting resistor are respectively connected with the drain of the charge field effect transistor, and the source of the charge field effect transistor is connected with the output end of the charging unit.

The first input end of the control module is connected with the second end of the current detection resistor, the control module comprises a first enabling end, a second enabling end and a third enabling end, the first enabling end is electrically connected with a grid of the discharge field effect transistor, the second enabling end is electrically connected with a grid of the charge field effect transistor, and the third enabling end is electrically connected with a grid of the short-circuit protection field effect transistor.

The control module is used for outputting a second enabling signal to close the charging field effect transistor, outputting a third enabling signal to close the short-circuit protection field effect transistor, outputting a first enabling signal to the discharging field effect transistor within a preset time to close the discharging field effect transistor, and outputting a first enabling signal to turn off the discharging field effect transistor when the short circuit of the loop is detected through the current detection resistor.

Optionally, the control module is further configured to output a third enable signal within a preset delay time after the discharging fet is turned off, so as to turn off the short-circuit protection fet.

Optionally, the control module includes a comparator and a control unit; the first input end of the comparator is electrically connected with the reference voltage end, the second input end of the comparator is electrically connected with the second end of the current detection resistor, and the output end of the comparator is electrically connected with the control unit and used for comparing the output voltage of the second end of the current detection resistor with the reference voltage and outputting the comparison result to the control unit; and the control unit is used for controlling the switching-off and the switching-on of the discharge field effect transistor according to the comparison result.

Optionally, the charging unit includes a load and a battery pack charging power supply, an input end of the load and an input end of the battery pack charging power supply are respectively connected to the positive electrode of the battery pack, and an output end of the load and an output end of the battery pack charging power supply are respectively connected to the source stage of the charging field effect transistor.

Optionally, the current limiting resistor is a thermal sensitive semiconductor resistor.

Optionally, the discharge field effect transistor, the charge field effect transistor and the short-circuit protection field effect transistor are all P-type field effect transistors.

Optionally, the battery pack is formed by connecting a plurality of battery cells in series.

In a second aspect, an embodiment of the present invention further provides a battery pack short-circuit protection circuit method, which is applicable to a battery pack short-circuit protection circuit device, where the battery pack short-circuit protection circuit device includes a battery pack, a current detection resistor, a discharge field-effect transistor, a charge field-effect transistor, a short-circuit protection field-effect transistor, a current limiting resistor, a charging unit, and a control module;

the positive electrode of the battery pack is connected with the input end of the charging unit; the negative electrode of the battery pack is connected with the first end of the current detection resistor, the second end of the current detection resistor is respectively connected with the drain of the discharge field effect transistor and the drain of the short-circuit protection field effect transistor, the source of the short-circuit protection field effect transistor is connected with the first end of the current limiting resistor, the source of the discharge field effect transistor and the second end of the current limiting resistor are respectively connected with the drain of the charge field effect transistor, and the source of the charge field effect transistor is connected with the output end of the charging unit.

The first input end of the control module is connected with the second end of the current detection resistor, the control module comprises a first enabling end, a second enabling end and a third enabling end, the first enabling end is electrically connected with a grid of the discharge field effect transistor, the second enabling end is electrically connected with a grid of the charge field effect transistor, and the third enabling end is electrically connected with a grid of the short-circuit protection field effect transistor.

The battery pack short-circuit protection circuit method comprises the following steps:

after power-on, outputting a second enabling signal to close the charging field effect transistor, outputting a third enabling signal to close the short-circuit protection field effect transistor, and outputting a first enabling signal within a preset time to close the short-circuit protection field effect transistor,

when the short circuit of the loop is detected through the current detection resistor, a first enabling signal is output to enable the discharging field effect transistor to be turned off.

Optionally, when the short circuit of the loop is detected by the current detection resistor, after outputting a first enable signal to turn off the discharge field effect transistor, the method further includes:

and outputting a third enabling signal within a preset time delay time to turn off the short-circuit protection field effect transistor.

Optionally, after power-on, performing initialization configuration and self-checking.

The embodiment of the invention discloses a battery pack short-circuit protection circuit device, which comprises a battery pack, a current detection resistor, a discharge field effect transistor, a charge field effect transistor, a short-circuit protection field effect transistor, a current limiting resistor, a control module and a charging unit, wherein the current detection resistor is connected with the charge field effect transistor; the battery pack, the current detection resistor, the discharge electric field effect tube, the charge field effect tube and the charge unit are sequentially connected in series, a short circuit field effect tube and a current limiting resistor are connected in parallel at two ends of the discharge field effect tube, the control module is respectively electrically connected with the current detection resistor, the discharge field effect tube, the charge field effect tube and the short circuit protection field effect tube, an enabling signal is output to enable the charge field effect tube to be closed and the short circuit protection field effect tube to be closed, the enabling signal is output to enable the discharge field effect tube to be closed within preset time, and the enabling signal is output to enable the discharge field effect tube to be turned off when the short circuit of a loop is. The problems that in the prior art, short-circuit protection is realized through a transient diode, absorption capacity is limited, protection times are limited and the like are solved, and the effects that a short-circuit protection circuit is simple and reliable, low in cost, free of short-circuit protection times and the like are achieved. After the discharge field effect transistor is turned off, the charge field effect transistor and the short-circuit protection field effect transistor still work, and the induced voltage generated when the short circuit occurs is not directly applied to the discharge field effect transistor, so that the voltage-resistant grade of the field effect transistor is not limited.

Drawings

Fig. 1 is a schematic diagram of a battery short-circuit protection circuit device according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a battery short-circuit protection circuit device according to a second embodiment of the present invention;

fig. 3 is a flowchart of a method for protecting a short circuit of a battery pack according to a third embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.