Battery protection circuit, protection board and battery

Abstract

The utility model provides a battery protection circuit, a protection board and a battery. The battery protection circuit comprises a voltameter IC and a fuse. The positive input pin of the battery current error amplifier of the voltameter IC is connected with one end of the fuse, and the negative input pin of the battery current error amplifier of the voltameter IC is connected with the other end of the fuse. According to the battery protection circuit provided by the utility model, the fuse is used for replacing a precision resistor as a current detection component, so that the current detection cost of the battery PCM protection board is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to a battery protection circuit, a protection board and a battery. Background Art

[0002] At present, the detection circuit on the battery PCM (Protection Circuit Module) protection board generally uses precision resistors to convert current. The current detection method is: the voltage difference V across the precision resistor is detected by the fuel meter IC (Integrated Circuit), and the stability of the precision resistor R is used to obtain the current I of the battery PCM protection board circuit through Ohm's law I=V / R.

[0003] However, due to the existence of precision resistors, the cost of current detection on the battery PCM protection board is increased. Utility Model Content

[0004] Therefore, the technical problem to be solved by the utility model is to solve the problem that the precision resistor is provided in the relevant battery PCM protection board, which increases the cost of current detection of the battery PCM protection board, thereby providing a battery protection circuit, a protection board and a battery.

[0005] In a first aspect, an embodiment of the utility model provides a battery protection circuit, comprising:

[0006] A fuel gauge IC and a fuse; a positive input pin of a battery current error amplifier of the fuel gauge IC is connected to one end of the fuse, and a negative input pin of the battery current error amplifier of the fuel gauge IC is connected to the other end of the fuse.

[0007] Optionally, a battery protection circuit further includes:

[0008] A connector is connected to the fuel gauge IC.

[0009] Optionally, a battery protection circuit further includes:

[0010] A first field effect transistor, wherein a gate of the first field effect transistor is connected to the fuel gauge IC, and a source of the first field effect transistor is connected to the connector.

[0011] Optionally, the first field effect transistor is an N-type MOS transistor.

[0012] Optionally, it also includes:

[0013] A second field effect transistor, wherein a gate of the second field effect transistor is connected to the fuel gauge IC, a drain of the second field effect transistor is connected to the drain of the first field effect transistor, and a source of the second field effect transistor is connected to the fuse.

[0014] Optionally, the second field effect transistor is an N-type MOS transistor.

[0015] Optionally, it also includes:

[0016] A third field effect transistor, wherein a gate of the third field effect transistor is connected to the fuel gauge IC, a drain of the third field effect transistor is connected to the fuse, and a source of the third field effect transistor is connected to the connector.

[0017] Optionally, the third field effect transistor is an N-type MOS tube.

[0018] In a second aspect, an embodiment of the utility model provides a battery protection board, including: a battery protection circuit; the battery protection circuit is integrated on the battery protection board.

[0019] In a third aspect, an embodiment of the utility model provides a battery, comprising:

[0020] At least one battery cell is connected to a battery protection circuit.

[0021] The technical solution of the utility model has the following advantages:

[0022] The utility model provides a battery protection circuit, including a fuel gauge IC and a fuse; the positive input pin of the battery current error amplifier of the fuel gauge IC is connected to one end of the fuse, and the negative input pin of the battery current error amplifier of the fuel gauge IC is connected to the other end of the fuse. The utility model provides a battery protection circuit, which uses a fuse to replace a precision resistor as a current detection component on the basis of an existing battery PCM protection board, thereby reducing the cost of current detection of the battery PCM protection board. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 It is a structural schematic diagram of a battery PCM protection board provided with a precision resistor in the prior art;

[0025] Figure 2 The figure is a structural diagram of a specific example of a battery protection circuit in an embodiment of the present utility model.

[0026] In the figure, 1-electricity meter IC; 2-fuse; 3-connector; 4-first field effect transistor; 5-second field effect transistor; 6-third field effect transistor; 7-battery cell. DETAILED DESCRIPTION

[0027] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "upper end", "interior", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0029] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "setting" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements, it can be a wireless connection, or it can be a wired connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0031] like Figure 1 As shown in the figure, in the relevant battery PCM protection board, the current passes through P+ and P- in the main circuit to charge and discharge the battery cell. The current passes through the precision resistor, forming a voltage difference across the precision resistor. The fuel gauge IC detects the voltage difference across the precision resistor. Since the resistance of the precision resistor is very stable, the fuel gauge IC can use Ohm's law to divide the voltage difference by the resistance of the precision resistor to obtain the current, so the current can be displayed. However, due to the existence of precision resistors, the cost of current detection is relatively high; Figure 1In the figure, 2nd IC refers to the secondary protection IC, which is an independent protection unit parallel to the fuel gauge. It has the function of overvoltage protection by monitoring the voltage of each battery cell.

[0032] In order to solve the above problems, the utility model provides a battery protection circuit, such as Figure 2 As shown, including:

[0033] A fuel gauge IC1 and a fuse (Fuse) 2; a positive input pin of a battery current error amplifier of the fuel gauge IC1 is connected to one end of the fuse 2, and a negative input pin of the battery current error amplifier of the fuel gauge IC1 is connected to the other end of the fuse 2.

[0034] Specifically, the fuel gauge (Gauge) IC detects the voltage difference between the two ends of the fuse 2 and converts it into current using Ohm's law, and then obtains the battery PCM protection board for current detection.

[0035] The battery protection circuit provided in this embodiment uses a fuse 2 to replace a precision resistor as a current detection component on the basis of an existing battery PCM protection board, thereby reducing the cost of current detection of the battery PCM protection board.

[0036] In an optional embodiment, it also includes:

[0037] Connector 3: Connector 3 is connected to the fuel gauge IC1.

[0038] Specifically, Figure 2 As shown, the connector 3 includes an input positive electrode P+, ​​an input negative electrode P−, a clock CLK and a data terminal DAT, wherein the clock CLK and the data terminal DAT are both connected to the electric meter IC1 .

[0039] In an optional embodiment, it also includes:

[0040] A first field effect transistor (MOSFET) 4 , wherein a gate of the first field effect transistor 4 is connected to the electric meter IC1 , and a source of the first field effect transistor 4 is connected to the connector 3 .

[0041] Specifically, the source of the first field effect transistor 4 is connected to the input positive electrode P+ in the connector 3 .

[0042] Furthermore, the first field effect transistor 4 is an N-type MOS transistor.

[0043] In an optional embodiment, it also includes:

[0044] The second field effect transistor 5 has a gate connected to the electricity meter IC1 , a drain connected to the drain of the first field effect transistor 4 , and a source connected to the fuse 2 .

[0045] Specifically, the second field effect transistor 5 adopts an N-type MOS tube

[0046] In an optional embodiment, it also includes:

[0047] The third field effect transistor 6 has a gate connected to the electricity meter IC1 , a drain connected to the fuse 2 , and a source connected to the connector 3 .

[0048] Specifically, the first field effect transistor 4 , the second field effect transistor 5 and the third field effect transistor 6 are all turned on and off by the electricity meter IC1 .

[0049] Furthermore, the third field effect transistor 6 is an N-type MOS transistor.

[0050] The utility model also provides a battery protection board, comprising: a battery protection circuit; the battery protection circuit is integrated on the battery protection board.

[0051] The utility model also provides a battery protection board, comprising:

[0052] At least one battery cell (Cell), wherein the battery cell is connected to a battery protection circuit.

[0053] Specifically, the battery cell is connected to the fuel gauge IC1 and the fuse 2 in the battery protection circuit, and the battery cell is connected to the input negative electrode P- in the connector 3 .

[0054] Furthermore, the battery cell serves as an energy storage unit and has the function of charging and storing.

[0055] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention of the utility model.

Claims

1. A battery protection circuit, characterized in that: include: Fuel gauge IC and fuse; A positive input pin of a battery current error amplifier of the fuel gauge IC is connected to one end of the fuse, and a negative input pin of a battery current error amplifier of the fuel gauge IC is connected to the other end of the fuse.

2. The battery protection circuit according to claim 1, characterized in that: Also includes: A connector is connected to the fuel gauge IC.

3. The battery protection circuit according to claim 2, characterized in that: Also includes: A first field effect transistor, wherein a gate of the first field effect transistor is connected to the fuel gauge IC, and a source of the first field effect transistor is connected to the connector.

4. The battery protection circuit according to claim 3, characterized in that: The first field effect transistor is an N-type MOS tube.

5. The battery protection circuit according to claim 3, characterized in that: Also includes: A second field effect transistor, wherein a gate of the second field effect transistor is connected to the fuel gauge IC, a drain of the second field effect transistor is connected to the drain of the first field effect transistor, and a source of the second field effect transistor is connected to the fuse.

6. The battery protection circuit according to claim 5, characterized in that: The second field effect transistor is an N-type MOS tube.

7. The battery protection circuit according to claim 2, characterized in that: Also includes: A third field effect transistor, wherein a gate of the third field effect transistor is connected to the fuel gauge IC, a drain of the third field effect transistor is connected to the fuse, and a source of the third field effect transistor is connected to the connector.

8. The battery protection circuit according to claim 7, characterized in that: The third field effect transistor is an N-type MOS tube.

9. A battery protection board, characterized in that: The battery protection circuit comprises the battery protection circuit as claimed in any one of claims 1 to 8; the battery protection circuit is integrated on the battery protection board.

10. A battery, characterized in that: include: At least one battery cell, wherein the battery cell is connected to the battery protection circuit according to any one of claims 1 to 8.

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