A battery charger

Abstract

The application discloses a battery charger, comprising a charging interface, N charging positions, a first control module and a switch circuit. The charging interface comprises a charging positive electrode pin and a ground pin; each charging position comprises a battery positive electrode connecting terminal and a battery negative electrode connecting terminal, the battery negative electrode connecting terminal of the first charging position is connected to the ground pin, and the battery positive electrode connecting terminal of the Nth charging position is connected to the charging positive electrode pin; the first control module is connected to at least one of the N battery positive electrode connecting terminals; the switch circuit comprises a switch circuit first end, a switch circuit second end and a switch circuit control end, the switch circuit first end is connected to the charging positive electrode pin, the switch circuit second end is connected to the battery positive electrode connecting terminal of the Nth charging position, and the switch circuit control end is connected to the first control module. In a first state, the N battery positive electrode connecting terminals are connected in parallel, and the N battery negative electrode connecting terminals are connected in parallel.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of charging devices, in particular to a battery charger which can be used as a power bank. BACKGROUND

[0002] Different battery chargers are suitable for different charging batteries, and the charging voltage and charging current are not the same. Therefore, if the wrong charging battery is used, safety problems will occur. The current charger lacks safety protection measures for the use of illegal batteries. SUMMARY

[0003] A series of simplified concepts are introduced in the summary section, which will be further described in detail in the specific embodiment section. The summary section of the present application does not mean to attempt to limit the key features and necessary technical features of the claimed technical solution, nor does it mean to attempt to determine the protection scope of the claimed technical solution.

[0004] To at least partially solve the above problems, the present application provides a battery charger, which comprises:

[0005] a charging interface for connecting with an external power supply device, the charging interface comprising a charging positive pole pin and a ground pin;

[0006] N charging positions, N being a positive integer, each of the charging positions being used for removably placing a charging battery, and each of the charging positions being provided with a battery positive pole connecting terminal for connecting a positive pole of the charging battery and a battery negative pole connecting terminal for connecting a negative pole of the charging battery, wherein the battery negative pole connecting terminal of the first charging position is used for connecting to the ground pin, and the battery positive pole connecting terminal of the Nth charging position is used for connecting to the charging positive pole pin;

[0007] a first control module connected to at least one of the N battery positive pole connecting terminals; and

[0008] a switching circuit comprising a switching circuit first end, a switching circuit second end and a switching circuit control end, the switching circuit control end being configured for controlling the on-off of the circuit between the switching circuit first end and the switching circuit second end, the switching circuit first end and the switching circuit second end being connected in series between the charging positive pole pin and the battery positive pole connecting terminal of the Nth charging position, the switching circuit first end being connected to the charging positive pole pin, the switching circuit second end being connected to the battery positive pole connecting terminal of the Nth charging position, and the switching circuit control end being connected to the first control module,

[0009] The battery charger comprises a first state in which N battery positive connection terminals are connected in parallel and N battery negative connection terminals are connected in parallel.

[0010] According to the application, the battery charger can charge N batteries in the first state, and the first control module can monitor the charging voltage of the batteries to disconnect the circuit between the charging positive pin and the battery positive connection terminal and stop charging the illegal battery when the illegal battery is used.

[0011] Optionally, the switch circuit comprises:

[0012] a first field effect transistor, a drain of the first field effect transistor being connected to the charging positive pin;

[0013] a second field effect transistor, a source of the second field effect transistor being connected to a source of the first field effect transistor, and a drain of the second field effect transistor being connected to the Nth battery positive connection terminal of the charging potential; and

[0014] a first triode, an emitter of the first triode being grounded, a base of the first triode being connected to the first control module, and a collector of the first triode being connected to a gate of the first field effect transistor and a gate of the second field effect transistor,

[0015] wherein the drain of the first field effect transistor is a first end of the switch circuit, the drain of the second field effect transistor is a second end of the switch circuit, and the base of the first triode is a control end of the switch circuit.

[0016] According to the application, the switch circuit is simple to control and stable in performance.

[0017] Optionally, the first control module is connected to all N battery positive connection terminals.

[0018] According to the application, the first control module monitors the charging voltage of all charging batteries.

[0019] Optionally, for each charging potential, in the first state, a PTC thermistor or a power resistor is connected in series between the battery positive connection terminal and the Nth battery positive connection terminal of the charging potential, or a PTC thermistor or a power resistor is connected in series between the battery negative connection terminal and the ground pin.

[0020] According to the application, when charging the batteries, each battery is connected in series with a PTC thermistor or a power resistor. When an illegal battery is used, the PTC thermistor or the power resistor can effectively suppress the charging current and protect the battery charger.

[0021] Optionally, the battery charger further comprises a second state in which the battery positive connection terminal of a previous charging level is connected to the battery negative connection terminal of a next charging level.

[0022] According to the present application, the battery charger can also be used as a power bank.

[0023] Optionally, the battery charger further comprises a switch assembly for user operation, the switch assembly being connected to at least part of the N battery positive connection terminals and the N battery negative connection terminals, the switch assembly comprising the first state and the second state, wherein,

[0024] When the switch assembly is in the first state, the N battery positive connection terminals are connected in parallel, and the N battery negative connection terminals are connected in parallel,

[0025] When the switch assembly is in the second state, the battery positive connection terminal of a previous charging level is connected to the battery negative connection terminal of a next charging level.

[0026] According to the present application, the working state of the battery charger is controlled by the switch assembly.

[0027] Optionally, the switch assembly comprises at least 2N-2 single-pole double-throw switches, the battery positive connection terminal of a first charging level, the battery negative connection terminal of an Nth charging level, and each of the battery positive connection terminal and the battery negative connection terminal of a second to an (N-1)th charging level are connected to one of the 2N-2 single-pole double-throw switches,

[0028] wherein,

[0029] When M is an odd number, the fixed terminal of an Mth single-pole double-throw switch is connected to the battery positive connection terminal of a (M+1) / 2th charging level, the first free terminal of the Mth single-pole double-throw switch is used to be connected to the battery positive connection terminal of an Nth charging level, and the second free terminal of the Mth single-pole double-throw switch is connected to the second free terminal of an (M+1)th single-pole double-throw switch.

[0030] When M is an even number, the fixed terminal of an Mth single-pole double-throw switch is connected to the battery negative connection terminal of a (M+2) / 2th charging level, the first free terminal of the Mth single-pole double-throw switch is used to be connected to the ground, and the second free terminal of the Mth single-pole double-throw switch is connected to the second free terminal of an (M-1)th single-pole double-throw switch.

[0031] All 2N-2 single-pole double-throw switches are configured to synchronously switch the connection state of the fixed end and the free end, in the first state, the fixed end of all 2N-2 single-pole double-throw switches is connected with the first free end, in the second state, the fixed end of all 2N-2 single-pole double-throw switches is connected with the second free end.

[0032] According to the application, the switch assembly is simple in control and stable in performance.

[0033] Optionally,

[0034] The first free end of the first single-pole double-throw switch in the 2N-2 single-pole double-throw switches is connected in series with the positive electrode connection terminal of the Nth charging potential through the PTC thermistor or power resistor;

[0035] The first free end of the 2N-2 single-pole double-throw switch in the 2N-2 single-pole double-throw switches is connected in series with the ground pin through the PTC thermistor or power resistor;

[0036] The first free end of the Mth single-pole double-throw switch in all 2N-2 single-pole double-throw switches is connected in series with the ground pin, or the first free end of the M+1 single-pole double-throw switch is connected in series with the positive electrode connection terminal of the Nth charging potential, wherein M is an even number less than 2N-2.

[0037] According to the application, the PTC thermistor or power resistor is flexibly arranged in series with the battery.

[0038] Optionally, the switch assembly further comprises a first additional single-pole double-throw switch, and the first additional single-pole double-throw switch is configured to synchronously switch the connection state of the fixed end and the free end with all 2N-2 single-pole double-throw switches.

[0039] The fixed end of the first additional single-pole double-throw switch is connected to the first control module, one of the first free end and the second free end of the first additional single-pole double-throw switch is connected to the positive electrode connection terminal of the Nth charging potential, and the other of the first free end and the second free end of the first additional single-pole double-throw switch is connected to the negative electrode connection terminal of the first charging potential.

[0040] According to the application, when the charging batteries are connected in parallel or connected in series in turn, the voltage signal transmitted by the first additional single-pole double-throw switch to the first control module is different, and the first control module can determine whether the battery charger is in the first state or the second state.

[0041] Optionally, the switch assembly further comprises a second additional single-pole double-throw switch, and the second additional single-pole double-throw switch is configured to synchronously switch the connection state of the fixed terminal and the free terminal with all the 2N-2 single-pole double-throw switches.

[0042] The fixed terminal of the second additional single-pole double-throw switch is connected to the first control module, one of the first free terminal and the second free terminal of the second additional single-pole double-throw switch is connected to the Nth battery positive connection terminal of the charging potential, and the other of the first free terminal and the second free terminal of the second additional single-pole double-throw switch is connected to the first battery negative connection terminal of the charging potential.

[0043] According to the present application, the second additional single-pole double-throw switch is also used to assist the first control module to determine whether the battery charger is in the first state or the second state, so as to ensure that the first control module can know whether the charger is in the first state or the second state through double insurance.

[0044] Optionally, the charging interface is configured as a Type-C interface, the charging positive pin is a VBUS pin of the Type-C interface, and the CC1 pin and the CC2 pin of the Type-C interface are connected to the first control module.

[0045] According to the present application, the charging interface adopts the Type-C interface, which has wide adaptability.

[0046] Optionally, the power pin of the first control module is connected to the charging positive pin and the Nth battery positive connection terminal of the charging potential.

[0047] According to the present application, in the first state, the charging positive pin supplies power to the first control module; and in the second state, the N charging batteries supply power to the first control module.

[0048] Optionally, the battery charger further comprises a first voltage stabilizing module, the first voltage stabilizing module comprises a first voltage stabilizing module input end and a first voltage stabilizing module output end, and the first voltage stabilizing module is configured to output a direct-current voltage signal with a constant voltage value at the first voltage stabilizing module output end when a high-level signal is input at the first voltage stabilizing module input end,

[0049] Among them, the Nth battery positive connection terminal of the charging potential and the charging positive pin are connected to the first voltage stabilizing module input end, and the power pin of the first control module is connected to the first voltage stabilizing module output end.

[0050] According to the present application, the first voltage stabilizing module provides a stable working voltage for the first control module.

[0051] Optionally, the battery charger further comprises:

[0052] a first diode, a positive electrode of the first diode being connected to the battery positive connection terminal of the Nth charging potential, and a negative electrode of the first diode being connected to the first voltage stabilizing module input end; and

[0053] a second diode, a positive electrode of the second diode being connected to the charging positive pin, and a negative electrode of the second diode being connected to the first voltage stabilizing module input end.

[0054] According to the present application, the first diode and the second diode isolate the charging positive pin of the charging interface from the battery positive connection terminal of the Nth charging potential.

[0055] Optionally, the battery charger further comprises:

[0056] a first indicator light, a first end of the first indicator light being connected to the first control module, and a second end of the first indicator light being connected to the first voltage stabilizing module output end; and

[0057] a second indicator light, a first end of the second indicator light being connected to the first control module, and a second end of the second indicator light being connected to the first voltage stabilizing module output end.

[0058] According to the present application, the first indicator light and the second indicator light are used to indicate the public state of the charger.

[0059] Optionally,

[0060] the first indicator light is configured as a first light emitting diode, the first end of the first indicator light being a positive electrode of the first light emitting diode, and the second end of the first indicator light being a negative electrode of the first light emitting diode; and / or

[0061] the second indicator light is configured as a second light emitting diode, the first end of the second indicator light being a positive electrode of the second light emitting diode, and the second end of the second indicator light being a negative electrode of the second light emitting diode.

[0062] According to the present application, the first indicator light and the second indicator light are simple to control, stable in performance, and low in cost.

[0063] Optionally, the first control module is configured to, in the first state, detect a voltage Up of at least one of the N battery positive connection terminals, and when the voltage Up is lower than a preset voltage threshold, send an off signal to the switch circuit control end, so that the circuit between the first end of the switch circuit and the second end of the switch circuit is disconnected.

[0064] According to the present application, when an illegal battery is used, the charging voltage decreases, so that the first control module disconnects the charging circuit.

[0065] Optionally,

[0066] The rechargeable battery is a lithium rechargeable battery; and / or

[0067] The preset voltage threshold is 2.8 to 4.3V.

[0068] According to the present application, the battery charger is suitable for lithium rechargeable batteries. The charging voltage of the legal battery is 2.8 to 4.3V. BRIEF DESCRIPTION OF DRAWINGS

[0069] The following drawings for the present application are hereby incorporated in and constitute a part of the present application for the purpose of understanding the present application. The embodiments of the present application and its description shown in the drawings are used to explain the principles of the present application.

[0070] In the drawings:

[0071] Figure 1 is a perspective exploded schematic view of a battery charger according to a preferred embodiment of the present application;

[0072] Figure 2 is Figure 1 is a schematic view of a first part of the circuit of the battery charger shown in

[0073] Figure 3 is Figure 2 is a schematic view of another connection of part A of the circuit in

[0074] Figure 4 is Figure 2 is a schematic view of yet another connection of part A of the circuit in

[0075] Figure 5 is Figure 1 is a schematic view of a second part of the circuit of the battery charger shown in

[0076] Figure 6 is Figure 1 is a schematic view of a third part of the circuit of the battery charger shown in

[0077] Figure 7 is Figure 1 is a schematic view of a fourth part of the circuit of the battery charger shown in

[0078] REFERENCE NUMERALS:

[0079] 10: upper cover

[0080] 20: battery compartment

[0081] 21 / 21A / 21B / 21C / 21D: charging position

[0082] 23 / 23A / 23B / 23C / 23D: battery positive connection terminal

[0083] 24 / 24A / 24B / 24C / 24D: battery negative connection terminal

[0084] 25 / 25A / 25B / 25C / 25D: rechargeable battery

[0085] 30: circuit board

[0086] 31: circuit

[0087] 33: CC1 pin

[0088] 34: CC2 pin

[0089] 35: button

[0090] 36: charging positive pin / VBUS pin

[0091] 37: PTC thermistor

[0092] 371: ground pin

[0093] 38: charging interface / Type-C interface

[0094] 39: first control module

[0095] 391: power supply pin

[0096] 310: switching circuit

[0097] 311: first field effect transistor

[0098] 312: second field effect transistor

[0099] 311D / 312D: drain

[0100] 311S / 312S: source

[0101] 311G / 312G: gate

[0102] 313: first triode

[0103] 313E: emitter

[0104] 313B: base

[0105] 313C: collector

[0106] 330: voltage dividing circuit

[0107] 331: first voltage dividing resistor

[0108] 332: second voltage dividing resistor

[0109] 333: Filter capacitor

[0110] 40: Bottom cover

[0111] 45: Button hole

[0112] 50: Indicator light

[0113] 51: First indicator light

[0114] 52: Second indicator light

[0115] 60: Switching assembly

[0116] 62 / 62A / 62B / 62C / 62D / 62E / 62F: Single-pole double-throw switch

[0117] 63 / 66C / 67C: Fixed end

[0118] 64 / 66A / 67A: First Free End

[0119] 65 / 66B / 67B: Second Free End

[0120] 66: First additional single-pole double-throw switch

[0121] 67: Second additional single-pole double-throw switch

[0122] 71: First Diode

[0123] 72: Second diode

[0124] 73: First voltage regulator module

[0125] 74: Input terminal of the first voltage regulator module

[0126] 75: Output terminal of the first voltage regulator module

[0127] 100: Battery charger Detailed Implementation

[0128] The following description provides numerous specific details to offer a more thorough understanding of this application. However, it will be apparent to those skilled in the art that this application can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described to avoid confusion with this application.

[0129] For a thorough understanding of the application, reference will be made to the following detailed description. It is appreciated that the embodiments are provided for the purpose of completeness and fullness of the disclosure of the application and to convey the full scope of the concepts of the exemplary embodiments to those skilled in the art. Obviously, the implementation of the application's embodiments is not limited to the particular details described herein. The preferred embodiments of the application are described in detail below, however, other embodiments of the application can be made without departing from the spirit of the application.

[0130] The ordinal numbers such as "first" and "second" cited in the present application are merely for identification and do not have any other meaning, such as a specific order, etc. Also, for example, the term "first member" itself does not imply the existence of a "second member", and the term "second member" itself does not imply the existence of a "first member". The use of the words "first", "second", and "third" and the like does not indicate any order but these words can be interpreted as names.

[0131] It should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", and similar terms used herein are for illustrative purposes only and are not limiting.

[0132] The present application provides a battery charger.

[0133] Now, exemplary embodiments according to the present application will be described in more detail with reference to the accompanying drawings.

[0134] As shown in Figure 1 , in a preferred embodiment, the battery charger 100 according to the present application includes an upper cover 10, a battery compartment 20, a circuit board 30, and a bottom cover 40.

[0135] The battery compartment 20 is used to accommodate N (N is a positive integer) rechargeable batteries 25 (see Figure 2 ). In the illustrated embodiment, N = 4. Of course, N can also be other values, such as 6, 8, etc. The battery compartment 20 includes N charging sites 21 corresponding to the N rechargeable batteries 25 respectively, each of which is used to removably place one rechargeable battery 25. Each charging site 21 includes a battery positive terminal 23 for connecting the positive pole of the rechargeable battery 25 and a battery negative terminal 24 for connecting the negative pole of the rechargeable battery 25. It can be understood that the battery positive terminal 23 also corresponds to the positive terminal of the battery 25, and the battery negative terminal 24 also corresponds to the negative terminal of the battery 25.

[0136] For example, when N=4, the battery compartment 20 is provided with charging sites 21A, 21B, 21C and 21D for respectively accommodating charging batteries 25A, 25B, 25C and 25D. The charging site 21A includes a battery positive terminal 23A for connecting the positive pole of the charging battery 25A and a battery negative terminal 24A for connecting the negative pole of the charging battery 25A. The charging site 21B includes a battery positive terminal 23B for connecting the positive pole of the charging battery 25B and a battery negative terminal 24B for connecting the negative pole of the charging battery 25B. The charging site 21C includes a battery positive terminal 23C for connecting the positive pole of the charging battery 25C and a battery negative terminal 24C for connecting the negative pole of the charging battery 25C. The charging site 21D includes a battery positive terminal 23D for connecting the positive pole of the charging battery 25D and a battery negative terminal 24D for connecting the negative pole of the charging battery 25D.

[0137] Preferably, the charging sites 21 are configured to be compatible with different models of charging batteries, for example, compatible with both size 5 batteries and size 7 batteries. Since different models of batteries have different sizes, for example, different lengths, the battery negative terminals 24 include a plurality of equally-potential connected negative sub-terminals for respectively contacting the negative poles of different models of charging batteries, and the different models of batteries share the battery positive terminals 23. As shown in Fig. 2, for example, for the charging site 21A, its battery negative terminal 24A includes a first negative sub-terminal 24P and a second negative sub-terminal 24Q. The size 5 batteries and the size 7 batteries share the battery positive terminal 23A, the size 5 batteries use the first negative sub-terminal 24P, and the size 7 batteries use the second negative sub-terminal 24Q. The battery negative terminals 24B, 24C and 24D are configured in the same manner as 24A. Figure 1

[0138] The bottom cover 40 is connected to the bottom of the battery compartment 20 to form part of the housing of the battery charger 100. The circuit board 30 is located between the bottom cover 40 and the battery compartment 20 and is supported by the bottom cover 40. The circuit board 30 is provided with a circuit 31 (as shown in Fig. 3) so that the charger 100 can achieve the intended functions. The N battery positive terminals 23 and the N battery negative terminals 24 are electrically connected to, or are provided on, the circuit board 30, so that the N battery positive terminals 23 and the N battery negative terminals 24 also become part of the circuit 31. The top cover 10 is used to fasten the battery compartment 20. Preferably, the top cover 10 is detachably connected to the bottom cover 40, or the top cover 10 is pivotally connected to the bottom cover 40, so that the top cover 10 can either open the charging sites 21 or cover the charging sites 21. Figures 2 to 7

[0139] As shown in Fig. 4, the battery charger 100 is provided with a battery compartment 20, a top cover 10, a bottom cover 40 and a circuit board 30. The battery compartment 20 is configured to accommodate N charging batteries 25, and is provided with N charging sites 21. The top cover 10 is configured to fasten the battery compartment 20. The bottom cover 40 is connected to the bottom of the battery compartment 20 to form part of the housing of the battery charger 100. The circuit board 30 is located between the bottom cover 40 and the battery compartment 20 and is supported by the bottom cover 40. The circuit board 30 is provided with a circuit 31 (as shown in Fig. 3) so that the charger 100 can achieve the intended functions. The N battery positive terminals 23 and the N battery negative terminals 24 are electrically connected to, or are provided on, the circuit board 30, so that the N battery positive terminals 23 and the N battery negative terminals 24 also become part of the circuit 31. The top cover 10 is used to fasten the battery compartment 20. Preferably, the top cover 10 is detachably connected to the bottom cover 40, or the top cover 10 is pivotally connected to the bottom cover 40, so that the top cover 10 can either open the charging sites 21 or cover the charging sites 21. Figure 2 ​​As shown, the battery charger 100 further comprises a charging interface 38 for connecting with an external power supply device, the charging interface 38 comprising a charging positive pole pin 36 and a ground pin 371. Preferably, the charging interface 38 is configured as a Type-C interface 38 comprising a VBUS pin 36, a ground pin 371, a CC1 pin 33 and a CC2 pin 34, wherein the VBUS pin 36 of the Type-C interface 38 is used for connecting the positive pole of the external power supply to introduce charging current to the charger 100. The VBUS pin 36 is also the charging positive pole pin 36. The ground pin 371 is used for grounding.

[0140] Specifically, the battery negative pole connection terminal 24A of the first charging position 21A of the battery charger 100 is used for grounding (in this application, grounding also means connecting to the ground pin 371), and the battery positive pole connection terminal 23 (for example, 23D) of the Nth charging position 21 (for example, 21D) is used for connecting to the charging positive pole pin 36, that is, connecting to the VBUS pin 36 of the Type-C interface 38.

[0141] The battery charger 100 has a first state, in which the N battery positive pole connection terminals 23 are connected in parallel, and the N battery negative pole connection terminals 24 are connected in parallel, so that when the charging interface 38 is connected with an external power supply device, the battery charger 100 can charge N charging batteries 25.

[0142] The battery charger 100 also has a second state, in which the battery positive pole connection terminal 23 of the previous charging position 21 is connected to the battery negative pole connection terminal 24 of the subsequent charging position 21. Thus, when N charging batteries 25 are placed in the battery compartment 20, in the second state, the N charging batteries 25 are connected in series one by one, so that the battery charger 100 can charge other electrical equipment and provide a charging voltage of 1.5N volts (for example, the voltage of each battery 25 is 1.5V), that is, in the second state, the charger 100 becomes a power bank 100. In the discharging state, the VBUS pin 36 of the Type-C interface 38 is used for connecting the charging positive pole of the external device.

[0143] As Figures 2 to 4As shown, the battery charger 100 also includes a switch assembly 60 for user operation. The switch assembly 60 is connected to at least a portion of the N battery positive connection terminals 23 and N battery negative connection terminals 24. The switch assembly 60 has a first state and a second state. When the switch assembly 60 is in the first state, the battery charger 100 is in the first state, with the N battery positive connection terminals 23 connected in parallel and the N battery negative connection terminals 24 connected in parallel, i.e., N batteries 25 connected in parallel. When the switch assembly 60 is in the second state, the battery charger 100 is in the second state, with the battery positive connection terminal 23 of the previous charging position 21 connected to the battery negative connection terminal 24 of the next charging position 21, i.e., N batteries 25 connected in series.

[0144] Preferably, such as Figure 1 As shown, a button 35 for user operation is connected to the circuit board 30. The button 35 is exposed through a button hole 45 in the bottom cover 40, making it accessible to the user. The button 35 is connected to a switch assembly 60 to control the state of the switch assembly 60. The button 35 is, for example, a self-locking button, having a first locked state and a second locked state. When the button 35 is in the first locked state, the switch assembly 60 is in the first state; when the button 35 is in the second locked state, the switch assembly 60 is in the second state. For example, when the user presses the button 35, each press switches the button 35 between the first and second locked states, and the switch assembly 60 switches between the first and second states. Thus, by pressing the button 35, the user changes the operating state of the charger 100, switching the charger 100 between charger function and power bank function.

[0145] To achieve the parallel-to-series conversion of the aforementioned N rechargeable batteries 25, specifically, as follows: Figures 2 to 4 As shown, in circuit 31, the switching assembly 60 includes at least 2N-2 single-pole double-throw switches 62. Each single-pole double-throw switch 62 includes a stationary terminal 63, a first free terminal 64, and a second free terminal 65. The stationary terminal 63 is either connected to the first free terminal 64 or to the second free terminal 65, thus the single-pole double-throw switch 62 has two conducting states.

[0146] For example, in the illustrated embodiment, N=4, and the switching assembly 60 includes six single-pole double-throw (SPD) switches 62, 62A, 62B, 62C, 62D, 62E, and 62F. The stationary terminal 63 of SPD switch 62 is the lower connection point in the figure, the first free terminal 64 is the upper left connection point, and the second free terminal 65 is the upper right connection point. Only SPD switch 62F is shown with its stationary terminal and two free terminals marked; the structures of SPD switches 62A, 62B, 62C, 62D, and 62E are the same as 62F.

[0147] The negative terminal 24 of the first battery 25A of the first charging level 21 is connected to ground, and the positive terminal 23 of the Nth battery 25N of the Nth charging level 21 is connected to the charging positive pin 36. The positive terminal 23 and the negative terminal 24 of each of the batteries 25A-25N of the second to the Nth charging levels 21 are connected to one of the 2N-2 single-pole double-throw switches 62.

[0148] For example, the negative terminal 24A of the first battery 25A of the first charging level 21 is connected to ground. The positive terminal 23D of the fourth battery 25D of the fourth charging level 21 is connected to the charging positive pin 36. The positive terminal 23A of the first battery 25A, the negative terminal 24D of the fourth battery 25D, the negative terminal 24B and the positive terminal 23B of the second battery 25B, and the negative terminal 24C and the positive terminal 23C of the third battery 25C are sequentially connected to one of the six single-pole double-throw switches 62A, 62B, 62C, 62D, 62E, and 62F. Specifically, the positive terminal 23A of the first battery 25A is connected to the first single-pole double-throw switch 62A, the negative terminal 24B of the second battery 25B is connected to the second single-pole double-throw switch 62B, the positive terminal 23B of the second battery 25B is connected to the third single-pole double-throw switch 62C, the negative terminal 24C of the third battery 25C is connected to the fourth single-pole double-throw switch 62D, the positive terminal 23C of the third battery 25C is connected to the fifth single-pole double-throw switch 62E, and the negative terminal 24D of the fourth battery 25D is connected to the sixth single-pole double-throw switch 62F.

[0149] wherein, when M is odd, the fixed terminal 63 of the Mth single-pole double-throw switch 62 is connected to the positive terminal 23 of the (M+1) / 2th charging level 21, the first free terminal 64 of the Mth single-pole double-throw switch 62 is used to be connected to the positive terminal 23 of the Nth charging level 21 (i.e., used to be connected to the charging positive pin 36), and the second free terminal 65 of the Mth single-pole double-throw switch 62 is connected to the second free terminal 65 of the (M+1)th single-pole double-throw switch 62; when M is even, the fixed terminal 63 of the Mth single-pole double-throw switch 62 is connected to the negative terminal 24 of the (M+2) / 2th charging level 21, the first free terminal 64 of the Mth single-pole double-throw switch 62 is used to be connected to ground, and the second free terminal 65 of the Mth single-pole double-throw switch 62 is connected to the first free terminal 64 of the (M-1)th single-pole double-throw switch 62.

[0150] For example, when M is 1, the fixed terminal of the first single-pole double-throw switch 62A is connected to the positive terminal 23A of the first battery 25A, the second free terminal of the first single-pole double-throw switch 62A is connected to the second free terminal of the second single-pole double-throw switch 62B, and the first free terminal of the first single-pole double-throw switch 62A is connected to the battery positive connection terminal 23 of the Nth charging level 21.

[0151] When M is 2, the fixed terminal of the second single-pole double-throw switch 62B is connected to the negative terminal 24B of the second battery 25B, the second free terminal of the second single-pole double-throw switch 62B is connected to the second free terminal of the first single-pole double-throw switch 62A, and the first free terminal of the second single-pole double-throw switch 62B is connected to ground.

[0152] When M is 3, the fixed terminal of the third single-pole double-throw switch 62C is connected to the positive terminal 23B of the second battery 25B, the second free terminal of the third single-pole double-throw switch 62C is connected to the second free terminal of the fourth single-pole double-throw switch 62D, and the first free terminal of the third single-pole double-throw switch 62C is connected to the battery positive connection terminal 23 of the Nth charging level 21.

[0153] When M is 4, the fixed terminal of the fourth single-pole double-throw switch 62D is connected to the negative terminal 24C of the third battery 25C, the second free terminal of the fourth single-pole double-throw switch 62D is connected to the second free terminal of the third single-pole double-throw switch 62C, and the first free terminal of the fourth single-pole double-throw switch 62D is connected to ground.

[0154] When M is 5, the fixed terminal of the fifth single-pole double-throw switch 62E is connected to the positive terminal 23C of the third battery 25C, the second free terminal of the fifth single-pole double-throw switch 62E is connected to the second free terminal of the sixth single-pole double-throw switch 62F, and the first free terminal of the fifth single-pole double-throw switch 62E is connected to the battery positive connection terminal 23 of the Nth charging level 21.

[0155] When M is 6, the fixed terminal of the sixth single-pole double-throw switch 62F is connected to the negative terminal 24D of the fourth battery 25D, the second free terminal of the sixth single-pole double-throw switch 62F is connected to the second free terminal of the fifth single-pole double-throw switch 62E, and the first free terminal of the sixth single-pole double-throw switch 62F is connected to ground.

[0156] In which all 2N-2 single-pole double-throw switches 62 are configured to synchronously switch the connection state of the fixed terminal 63 and the free terminals (the first free terminal 64 and the second free terminal 65). In the first state, the fixed terminals 63 of all 2N-2 single-pole double-throw switches 62 are connected to the first free terminals 65, and in the second state, the fixed terminals 63 of all 2N-2 single-pole double-throw switches 62 are connected to the second free terminals 64.

[0157] For example, all six single-pole double-throw switches 62 are configured to synchronously switch the connection state between the stationary end 63 and the free ends (first free end 64 and second free end 65). Figure 2 As shown, in the first state, the stationary ends 63 of all six single-pole double-throw switches 62 are connected to the first free ends 64 (the lower connection points of all single-pole double-throw switches 62 are connected to the upper left connection point), thus connecting the four batteries 25A, 25B, 25C, and 25D in parallel (the negative terminals of all four batteries are grounded, and the positive terminals are connected to the charging positive terminal pin 36); Figure 3 and Figure 4 As shown, in the second state, the stationary ends 63 of all 2N-2 single-pole double-throw switches 62 are connected to the second free ends 65 (the lower connection points of all single-pole double-throw switches 62 are connected to the upper right connection point), so that the four batteries are connected in series in sequence (the negative terminal of the first battery 25A is grounded, and the positive terminal of the fourth battery 25D is connected to the charging positive terminal pin 36).

[0158] like Figure 5 As shown, the battery charger 100 also includes a first control module 39. The CC1 pin 33 and CC2 pin 34 of the Type-C interface 38 are connected to the first control module 39 (see electrical connection points J and K in the figure), so that the first control module 39 can communicate with externally connected devices.

[0159] like Figures 2 to 4 As shown, in order for the first control module 39 to correctly determine the operating state (first state or second state) of the battery charger 100 and establish normal communication with external devices, the switch assembly 60 further includes a first additional single-pole double-throw switch 66 and a second additional single-pole double-throw switch 67. The first additional single-pole double-throw switch 66 and the second additional single-pole double-throw switch 67 are configured to synchronously switch the connection state of the stationary end and the free end with all 2N-2 single-pole double-throw switches 62. That is, when the stationary end 63 of the single-pole double-throw switch 62 is connected to the first free end 64, the stationary end 66C of the first auxiliary single-pole double-throw switch 66 is connected to its first free end 66A, and the stationary end 67C of the second auxiliary single-pole double-throw switch 67 is connected to its first free end 67A; when the stationary end 63 of the single-pole double-throw switch 62 is connected to the second free end 65, the stationary end 66C of the first auxiliary single-pole double-throw switch 66 is connected to its second free end 66B, and the stationary end 67C of the second auxiliary single-pole double-throw switch 67 is connected to its second free end 67B.

[0160] The first control module 39 is, for example, a single-chip microcomputer. The fixed terminal 66C of the first additional single-pole double-throw switch 66 is connected to the first control module 39 (for example, an I / O pin of the first control module 39, in particular, a voltage input pin, see the electrical connection point C in the figure). One of the first free terminal 66A and the second free terminal 66B of the first additional single-pole double-throw switch 66 is connected to the negative electrode connection terminal 24A of the first charging position 21 (i.e., the ground pin 371, i.e., the ground). The other of the first free terminal 66A and the second free terminal 66B of the first additional single-pole double-throw switch 66 is connected to the positive electrode connection terminal 23 of the Nth charging position 21. The fixed terminal 67C of the second additional single-pole double-throw switch 67 is connected to the first control module 39 (for example, an I / O pin of the first control module 39, in particular, a voltage input pin, see the electrical connection point D in the figure). One of the first free terminal 67A and the second free terminal 67B of the second additional single-pole double-throw switch 67 is connected to the negative electrode connection terminal 24A of the first charging position 21. The other of the first free terminal 67A and the second free terminal 67B of the second additional single-pole double-throw switch 67 is connected to the positive electrode connection terminal 23 of the Nth charging position 21. Thus, in the first state and the second state, the first additional single-pole double-throw switch 66 and the second additional single-pole double-throw switch 67 deliver different voltage signals to the first control module 39, so that the control module 39 can know the working state of the charger 100.

[0161] In Figure 2 and Figure 3 In the embodiment shown in FIG. 6, the first free terminal 66A of the first additional single-pole double-throw switch 66 and the second free terminal 67B of the second additional single-pole double-throw switch 67 are connected to the negative electrode connection terminal 24A of the first charging position 21A, and the second free terminal 66B of the first additional single-pole double-throw switch 66 and the first free terminal 67A of the second additional single-pole double-throw switch 67 are connected to the positive electrode connection terminal 23 of the Nth charging position 21. In the embodiment shown in FIG. 7, the first free terminal 66A of the first additional single-pole double-throw switch 66 and the first free terminal 67A of the second additional single-pole double-throw switch 67 are connected to the negative electrode connection terminal 24A of the first charging position 21A, and the second free terminal 66B of the first additional single-pole double-throw switch 66 and the second free terminal 67B of the second additional single-pole double-throw switch 67 are connected to the positive electrode connection terminal 23 of the Nth charging position 21. Figure 4

[0162] It can be understood that in the present application, only one of the first additional single-pole double-throw switch 66 and the second additional single-pole double-throw switch 67 can be provided. Preferably, both the first additional single-pole double-throw switch 66 and the second additional single-pole double-throw switch 67 are used, so that when one of them fails, the other one can work.

[0163] Preferably, as​Figure 1 As shown, the charger 100 is provided with an indicator light 50 for indicating the working state of the charger 100. The indicator light 50 is also part of the circuit 31. For example, the indicator light 50 comprises a first indicator light 51 and a second indicator light 52. For example, the charger 100 is configured to cause the first indicator light 51 to light up and the second indicator light 52 to be off when the switch assembly 60 is in the first state, so that the first indicator light 51 is used to indicate that the charger 100 is in the working state of charging the battery. For example, the charger 100 is configured to cause the first indicator light 51 to be off and the second indicator light 52 to light up when the switch assembly 60 is in the second state, so that the second indicator light 52 is used to indicate that the charger 100 is in the working state of discharging the battery (power bank). Alternatively, the indicator light 50 is provided to light up in the form of flickering, for example, the first indicator light 51 flickers to indicate that the charger 100 is in the working state of charging the battery, and the second indicator light 52 flickers to indicate that the charger 100 is in the working state of discharging the battery. Alternatively, one of the first indicator light 51 and the second indicator light 52 lights up to indicate that the charger 100 is in the working state of charging the battery, and the first indicator light 51 and the second indicator light 52 light up at the same time to indicate that the charger 100 is in the working state of discharging the battery. Preferably, the first indicator light 51 is different in color from the second indicator light 52, which is more convenient for the user to distinguish. The first indicator light 51 and the second indicator light 52 can also indicate the working state of the charger 100 by other lighting modes, which will not be described here.

[0164] As shown in FIG. 1, the first control module 39 is connected to the first indicator light 51 and the second indicator light 52. Figure 6 As shown, the first end of the first indicator light 51 is connected to the first control module 39 (see the electrical connection point H in the figure), and the second end of the first indicator light 51 is used to be connected to the charging positive pin 36 and the battery positive connection terminal 23 of the Nth charging level 21 (see the electrical connection points E and F in the figure). The first end of the second indicator light 52 is connected to the first control module 39 (see the electrical connection point I in the figure), and the second end of the second indicator light 52 is used to be connected to the charging positive pin 36 and the battery positive connection terminal 23 of the Nth charging level 21 (see the electrical connection points E and F in the figure).

[0165] Preferably, the first indicator light 51 is configured as a first light-emitting diode. The first end of the first indicator light 51 is the negative terminal of the first light-emitting diode, and the second end of the first indicator light 51 is the positive terminal of the first light-emitting diode. Preferably, the second indicator light 52 is configured as a second light-emitting diode. The first end of the second indicator light 52 is the negative terminal of the second light-emitting diode, and the second end of the second indicator light 52 is the positive terminal of the second light-emitting diode.

[0166] When the fixed terminals of all the SPDT switches 62 are connected to the first free terminals, the fixed terminals of the first and second additional SPDT switches 66 and 67 are also connected to the first free terminals; when the fixed terminals of all the SPDT switches 62 are connected to the second free terminals, the fixed terminals of the first and second additional SPDT switches 66 and 67 are also connected to the second free terminals. That is, the first and second additional SPDT switches 66 and 67 follow the switch states of the switch assembly 60.

[0167] Thus, when the switch assembly 60 is in the first state, the fixed terminals of the first and second additional SPDT switches 66 and 67 are connected to the first free terminals, so that the first control module 39 determines that the switch assembly 60 is in the first state and the charger 100 is in the charging (slave) state. At this time, the charging positive pin 36 supplies power to the positive poles of the first and second indicator lights 51 and 52. The first control module 39 outputs corresponding voltages to the negative poles of the first and second indicator lights 51 and 52 to indicate the working state of the charger 100. For example, a low voltage is output to the negative pole of the first indicator light 51 to make the first indicator light 51 light up, a high voltage is output to the negative pole of the second indicator light 52 to make the second indicator light 52 not light up, or a high voltage is output to the negative pole of the first indicator light 51 to make the first indicator light 51 not light up, and a low voltage is output to the negative pole of the second indicator light 52 to make the second indicator light 52 light up.

[0168] Similarly, when the switch assembly 60 is in the second state, the fixed terminals of the first and second additional SPDT switches 66 and 67 are connected to the second free terminals, so that the first control module 39 determines that the switch assembly 60 is in the second state and the charger 100 is in the discharging (master) state. At this time, the battery positive connection terminal 23 of the Nth charging position 21 supplies power to the positive poles of the first and second indicator lights 51 and 52. The first control module 39 outputs corresponding voltages to the negative poles of the first and second indicator lights 51 and 52 to indicate the working state of the charger 100.

[0169] Specifically, as Figure 6As shown, the first end of the first indicator light 51 is connected to the first control module 39 (for example, one I / O pin of the first control module 39, see the electrical connection point H in the figure), and the second end of the first indicator light 51 is used to be connected to the battery positive connection terminal 23 of the charging positive pin 36 and the Nth charging potential 21. Thus, the first control module 39 controls the lighting of the first indicator light 51. The first end of the second indicator light 52 is connected to the first control module 39 (for example, one I / O pin of the first control module 39, see the electrical connection point I in the figure), and the second end of the second indicator light 52 is used to be connected to the battery positive connection terminal 23 of the charging positive pin 36 and the Nth charging potential 21. Thus, the first control module 39 controls the lighting of the second indicator light 52.

[0170] Therefore, the first additional single-pole double-throw switch 66 and the second additional single-pole double-throw switch 67 can determine the working state of the battery charger 100 by delivering different voltage signals to the first control module 39, and then control the negative voltage of the first indicator light 51 and the second indicator light 52 to indicate the working state of the battery charger 100. It can be understood that under such working principle, the voltage signals delivered by the first additional single-pole double-throw switch 66 and the second additional single-pole double-throw switch 67 to the first control module 39 can have multiple combinations, and the indication mode of the first indicator light 51 and the second indicator light 52 can also have multiple forms.

[0171] As Figure 6 As described above, the battery charger 100 further comprises a first diode 71 and a second diode 72. The positive electrode of the first diode 71 is connected to the battery positive connection terminal 23 of the Nth charging potential 21 (see the electrical connection point F in the figure), and the negative electrode of the first diode 71 is used to be connected to the second end of the first indicator light 51 and the second end of the second indicator light 52. The positive electrode of the second diode 72 is connected to the charging positive pin 36 (see the electrical connection point E in the figure), and the negative electrode of the second diode 72 is used to be connected to the second end of the first indicator light 51 and the second end of the second indicator light 52. Thus, the battery charger 100 can ensure the one-way conduction between the power supply positive and the indicator light 50 in the first state and the second state.

[0172] The battery charger 100 also includes a first voltage regulator module 73. The first voltage regulator module 73 includes a first voltage regulator input terminal 74 and a first voltage regulator output terminal 75. The first voltage regulator module 73 is configured such that when a high-level signal is input to the first voltage regulator input terminal 74, the first voltage regulator output terminal 75 outputs a constant DC voltage signal (e.g., a stable 3V, 5V, etc.). The cathodes of the first diode 71 and the second diode 72 are connected to the first voltage regulator input terminal 74, and the second terminals of the first indicator light 51 and the second indicator light 52 are connected to the first voltage regulator output terminal 75. Therefore, when a high-level signal is input to the first voltage regulator input terminal 74, the voltage value input to the second terminal of the indicator light 50 is constant. The voltage levels set by the first control module 39 at the electrical connection points I and H between the indicator light 50 and the first control module 39 can accurately control the illumination of the indicator light 50.

[0173] Meanwhile, the power supply pin 391 of the first control module 39 is connected to the output terminal 75 of the first voltage regulator module (see electrical connection point G in the figure). Thus, the first control module 39 is provided with a stable power supply voltage by the output terminal 75 of the first voltage regulator module.

[0174] In this application, button 35 enables the synchronous switching of the switching states of all 2N-2 single-pole double-throw switches 62, the first additional single-pole double-throw switch 66, and the second additional single-pole double-throw switch 67.

[0175] Preferably, the rechargeable battery 25 is a dry cell battery, such as a lithium rechargeable battery. That is, the battery charger 100 according to this application is preferably adapted for use with a lithium rechargeable battery.

[0176] like Figure 2 As shown, in order to detect that the battery charger 100 is using an illegal battery, the circuit 31 of the battery charger 100 also includes a switching circuit 310.

[0177] The switching circuit 310 includes a first terminal 311D, a second terminal 312D, and a control terminal 313B. The first terminal 311D and the second terminal 312D are connected in series between the charging positive pin 36 and the battery positive connection terminal 23 of the Nth charging position 21. Specifically, the first terminal 311D is connected to the charging positive pin 36, and the second terminal 312D is connected to the battery positive connection terminal 23 of the Nth charging position 21. The control terminal 313B is connected to the first control module 39 and is used to control the on / off state of the circuit between the first terminal 311D and the second terminal 312D.

[0178] The first control module 39 is configured to, in the first state, detect the voltage Up of at least one of the N battery positive connection terminals 23, and when the voltage Up is lower than a preset voltage threshold, send a turn-off signal to the switch circuit control terminal 313B, so that the circuit between the first terminal 311D of the switch circuit and the second terminal 312D of the switch circuit is disconnected. For example, in the case of using a lithium rechargeable battery, the preset voltage threshold is 2.8 to 4.3V. The charging voltage of a nickel-hydrogen rechargeable battery is usually 0.8 to 1.45V, which is lower than the charging voltage of a lithium rechargeable battery. Therefore, when the user uses an illegal battery (a nickel-hydrogen rechargeable battery), the first control module 39 can detect the abnormality of the charging voltage, so as to disconnect the circuit and make the charger 100 unable to work. Preferably, the first control module 39 can also prompt the user that an illegal battery is used through the first indicator light 51 and the second indicator light 52.

[0179] Preferably, the first control module 39 is connected to all the N battery positive connection terminals 23, so as to monitor whether all the batteries 25 are illegal batteries. As long as one of the N batteries 25 is an illegal battery, the first control module 39 disconnects the circuit between the charging positive pin 36 and the battery positive connection terminal 23.

[0180] Specifically, referring to Figure 2 and Figure 7 , the battery positive connection terminal 23 is connected to the first control module 39 through a voltage dividing circuit 330. The voltage dividing circuit 330 includes a first voltage dividing resistor 331 and a second voltage dividing resistor 332. The first voltage dividing resistor 331 and the second voltage dividing resistor 332 are connected in series between the battery positive connection terminal 23 and the ground. The common terminal of the first voltage dividing resistor 331 and the second voltage dividing resistor 332 is connected to the first control module 39. Taking N=4 as an example, the four battery positive connection terminals 23 are respectively connected to one voltage dividing circuit 330 (see the electrical connection points P, Q, R, S in the figure), and the common terminals of the first voltage dividing resistor 331 and the second voltage dividing resistor 332 of each voltage dividing circuit 330 are connected to the first control module 39 (see the electrical connection points T, U, V, W in the figure). The first voltage dividing resistor 331 and the second voltage dividing resistor 332 divide the charging voltage Up at the battery positive connection terminal 23, and the voltage at the common terminal of the first voltage dividing resistor 331 and the second voltage dividing resistor 332 is related to the voltage Up and can reflect the value of the voltage Up.

[0181] The voltage dividing circuit 330 can also include a capacitor 333. The capacitor 333 is connected in parallel with the second voltage dividing resistor 332 and functions to filter, which can eliminate the high-frequency interference at the common terminal of the first voltage dividing resistor 331 and the second voltage dividing resistor 332, so that the first control module 39 can accurately detect the value of the voltage Up.

[0182] Specifically, as Figure 2As shown, the switch circuit 310 includes a first field effect transistor 311, a second field effect transistor 312, and a first triode 313. The drain 311D of the first field effect transistor 311 is connected to the charging positive pin 36, the source 312S of the second field effect transistor 312 is connected to the source 311S of the first field effect transistor 311, and the drain 312D of the second field effect transistor 312 is connected to the battery positive terminal 23 of the Nth charging position 21. The emitter 313E of the first triode 313 is grounded, the base 313B of the first triode 313 is connected to the first control module 39 (see the electrical connection point L in the figure), and the collector 313C of the first triode 313 is connected to the gate 311G of the first field effect transistor 311 and the gate 312G of the second field effect transistor 312. Among them, the drain 311D of the first field effect transistor 311 is the first end 311D of the switch circuit, the drain 312D of the second field effect transistor 312 is the second end 312D of the switch circuit, and the base 313B of the first triode 313 is the control end 313B of the switch circuit.

[0183] In the first state, the charging positive pin 36 supplies power to the first control module 39. When the first control module 39 detects that the voltage Up of the battery positive terminal 23 is lower than the preset voltage threshold, it sends a turn-off signal to the base 313B of the first triode 313, thereby changing the voltage of the collector 313C of the first triode 313, so that the first field effect transistor 311 and the second field effect transistor 312 cannot be turned on, that is, the circuit between the drain 311D of the first field effect transistor 311 and the drain 312D of the second field effect transistor 312 is disconnected, to stop charging.

[0184] Compared with nickel-hydrogen rechargeable batteries, lithium rechargeable batteries not only have different charging voltages, but also have different charging currents. For example, the charging current of a lithium rechargeable battery is usually less than 700mA, while the charging current of a nickel-hydrogen rechargeable battery can reach 2-3A. Therefore, when using an illegal battery, the excessive charging current can cause damage to the components in the circuit 31.

[0185] In order to limit the charging current when using an illegal battery, as shown in FIG. 4, the switch circuit 310 is added to the circuit 31. Figures 2 to 4As shown, the circuit 31 is further provided with a PTC (Positive Temperature Coefficient) thermistor 37. For each charging position 21, in the first state, the PTC thermistor 37 is connected in series between the battery positive connection terminal 23 and the battery positive connection terminal 23 of the Nth charging position 21 (charging positive pole), or between the battery negative connection terminal 24 and the ground pin 371 (ground wire). That is, in the first state, each battery 25 is connected in series with the thermistor 37. When the battery 25 is an illegal battery, the charging current flowing through the battery 25 is large. The charging current also flows through the PTC thermistor 37, causing the PTC thermistor 37 to generate heat and rise in temperature. In turn, the resistance of the PTC thermistor 37 rises, causing the current flowing therethrough to decrease (e.g., below 100 mA), that is, causing the current flowing through the battery 25 to decrease, thereby protecting the circuit 31. At the same time, the resistance of the PTC thermistor 37 rises, the voltage drop across the PTC thermistor 37 increases, causing the voltage of the battery 25 to decrease, thereby assisting the first control module 39 in identifying the illegal battery.

[0186] As previously described, when the switch assembly 60 is in the first state, the charger 100 functions as a battery charger. In the charging state, the fixed end 63 of the single-pole double-throw switch 62 is connected to the first free end 64. Therefore, the PTC thermistor 37 is connected to the first free end 64 of the single-pole double-throw switch 62 to be connected in the circuit 31 in the charging state.

[0187] Preferably, the circuit 31 is provided with N PTC thermistors 37 corresponding to the N charging batteries 25, respectively, so that each charging battery 25 is connected in series with a PTC thermistor 37 to form a loop during charging.

[0188] In the first charging position 21, the first free end of the single-pole double-throw switch 62A connected to the first charging battery 25A is connected to the battery positive connection terminal 23 of the Nth charging position 21 via the PTC thermistor 37, and the first free end of the single-pole double-throw switch 62 connected to the Nth charging battery 25 is connected to the ground pin 371 via the PTC thermistor 37.

[0189] The positive and negative poles of the second to the (N-1)th rechargeable batteries 25 are connected with single-pole double-throw switches 62, and therefore, for the second to the (N-1)th rechargeable batteries 25, the PTC thermistor 37 can be connected to the single-pole double-throw switch 62 of the positive pole or to the single-pole double-throw switch 62 of the negative pole. Therefore, the first free end of the Mth single-pole double-throw switch 62 among the total 2N-2 single-pole double-throw switches 62 is provided (in series) with the PTC thermistor 37 between the ground pin 371, or the first free end of the (M+1)th single-pole double-throw switch 62 is provided (in series) with the PTC thermistor 37 between the positive pole connection terminal 23 of the Nth rechargeable battery 21. Here, M is an even number smaller than 2N-2.

[0190] In the illustrated embodiment, referring to Figures 2 to 4 When M=2, the 2nd single-pole double-throw switch 62B is connected to the negative pole of the second rechargeable battery 25B, and the 3rd single-pole double-throw switch 62C is connected to the positive pole of the second rechargeable battery 25B, and the PTC thermistor 37 can be provided (in series) between the first free end of the 2nd single-pole double-throw switch 62B and the ground wire (as shown in Figure 2 and Figure 3 ), or the PTC thermistor 37 can be provided (in series) between the first free end of the 3rd single-pole double-throw switch 62C and the positive pole of the rechargeable battery (as shown in Figure 4 When M=4, the 4th single-pole double-throw switch 62D is connected to the negative pole of the third rechargeable battery 25C, and the 5th single-pole double-throw switch 62E is connected to the positive pole of the third rechargeable battery 25C, and the PTC thermistor 37 can be provided (in series) between the first free end of the 4th single-pole double-throw switch 62D and the ground wire (as shown in Figure 2 and Figure 3 ), or the PTC thermistor 37 can be provided (in series) between the first free end of the 5th single-pole double-throw switch 62 and the positive pole of the rechargeable battery (as shown in Figure 4 .

[0191] Each of the PTC thermistors 37 described above can also be replaced by a power resistor, which can also serve the function of current-limiting protection.

[0192] The processes and steps described in all the preferred embodiments described above are merely examples. Unless adverse effects occur, various processing operations can be performed in a sequence different from the above-described processes. The sequence of the steps of the above-described processes can also be added, combined, or deleted according to actual needs.

[0193] The term "comprising," as used in this application, means "including," "containing," or "characterized by" and should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It should be understood that this term encompasses the terms "consisting of" and "consisting essentially of."

[0194] The term "attached" or "attach" as used herein includes a construction of one element to another by a fixation of the elements to one another, directly or indirectly, by a medium, such as a bond, welding, or the like; a construction of one element to another where the elements are formed in one piece with one another; and a construction of one element to another where the elements are formed in one piece with one another. This definition also applies to words of similar meaning, such as "connected," "coupled," "joined," "engage," "linking," "mounting," "bonding," "fixing," and the like. Finally, the degree terms such as "substantially," "approximately," and "about" as used herein mean an acceptable quantity of deviation of the modified term such that the end result is not significantly changed.

[0195] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application. The features described in one embodiment can be applied to another embodiment, unless the features are not compatible with the other embodiment or are otherwise stated.

[0196] The present application has been described by way of the above embodiments, but it should be understood that the above embodiments are for illustrative and descriptive purposes only and are not intended to limit the present application to the scope of the described embodiments. Furthermore, it will be understood by those skilled in the art that the present application is not limited to the above embodiments, and various modifications and changes can be made to the present application according to the teachings of the present application, and such modifications and changes fall within the scope of the present application claimed.

Claims

1. A battery charger characterized by comprising: The application relates to a charging device, comprising: a charging interface for connecting with an external power supply device, the charging interface comprising a charging positive pole pin and a grounding pin; N charging positions, N being a positive integer, each of the charging positions being used for placing a charging battery in a removable manner, each of the charging positions being provided with a battery positive pole connecting terminal for connecting a positive pole of the charging battery and a battery negative pole connecting terminal for connecting a negative pole of the charging battery, wherein the battery negative pole connecting terminal of the first charging position is used for connecting to the grounding pin, and the battery positive pole connecting terminal of the Nth charging position is used for connecting to the charging positive pole pin; a first control module connected to at least one of the N battery positive pole connecting terminals; and a switch circuit comprising a switch circuit first end, a switch circuit second end and a switch circuit control end, the switch circuit control end being configured for controlling the on-off of a circuit between the switch circuit first end and the switch circuit second end, the switch circuit first end and the switch circuit second end being connected in series between the charging positive pole pin and the battery positive pole connecting terminal of the Nth charging position, the switch circuit first end being connected to the charging positive pole pin, the switch circuit second end being connected to the battery positive pole connecting terminal of the Nth charging position, and the switch circuit control end being connected to the first control module; and a switch assembly for being operated by a user, the switch assembly being connected to at least part of the N battery positive pole connecting terminals and the N battery negative pole connecting terminals, wherein the switch assembly comprises a first state in which the N battery positive pole connecting terminals are connected in parallel and the N battery negative pole connecting terminals are connected in parallel, the switch assembly comprising at least 2N-2 single-pole double-throw switches, the battery positive pole connecting terminal of the first charging position, the battery negative pole connecting terminal of the Nth charging position and each of the battery positive pole connecting terminals and the battery negative pole connecting terminals of the second to the N-1th charging positions being connected to one of the 2N-2 single-pole double-throw switches, wherein when M is an odd number, a fixed end of the Mth single-pole double-throw switch is connected to the battery positive pole connecting terminal of the (M+1) / 2th charging position, a first free end of the Mth single-pole double-throw switch is used for connecting to the battery positive pole connecting terminal of the Nth charging position, and a second free end of the Mth single-pole double-throw switch is connected to a second free end of the M+1th single-pole double-throw switch; when M is an even number, a fixed end of the Mth single-pole double-throw switch is connected to the battery negative pole connecting terminal of the (M+2) / 2th charging position, a first free end of the Mth single-pole double-throw switch is used for grounding, and a second free end of the Mth single-pole double-throw switch is connected to a second free end of the M-1th single-pole double-throw switch, and in the first state, the fixed ends and the first free ends of all the 2N-2 single-pole double-throw switches are connected.

2. The battery charger of claim 1, wherein, The switch circuit comprises: a first field effect tube, a drain of the first field effect tube being connected to the charging positive pole pin; a second field effect transistor, a source of the second field effect transistor is connected to a source of the first field effect transistor, a drain of the second field effect transistor is connected to the Nth battery positive connection terminal of the Nth charging level; a first triode, an emitter of the first triode is grounded, a base of the first triode is connected to the first control module, a collector of the first triode is connected to a gate of the first field effect transistor and a gate of the second field effect transistor, wherein the drain of the first field effect transistor is a first end of the switch circuit, the drain of the second field effect transistor is a second end of the switch circuit, and the base of the first triode is a control end of the switch circuit.

3. The battery charger of claim 1, wherein, The first control module is connected to all N battery positive connection terminals.

4. The battery charger of claim 3, wherein, For each charging level, in the first state, a PTC thermistor or a power resistor is connected in series between the battery positive connection terminal and the Nth battery positive connection terminal of the Nth charging level, or a PTC thermistor or a power resistor is connected in series between the battery negative connection terminal and the ground pin.

5. The battery charger of claim 4, wherein, The switch assembly further comprises a second state, in which the battery positive connection terminal of the previous charging level is connected to the battery negative connection terminal of the subsequent charging level.

6. The battery charger of claim 5, wherein, All 2N-2 single-pole double-throw switches are configured to synchronously switch the connection state between the fixed end and the free end, in the first state, the fixed end of all 2N-2 single-pole double-throw switches is connected to the first free end, and in the second state, the fixed end of all 2N-2 single-pole double-throw switches is connected to the second free end.

7. The battery charger according to claim 6, wherein, a PTC thermistor or a power resistor is connected in series between the first free end of the first single-pole double-throw switch of the 2N-2 single-pole double-throw switches and the battery positive connection terminal of the Nth charging level; a PTC thermistor or a power resistor is connected in series between the first free end of the 2N-2 single-pole double-throw switch of the 2N-2 single-pole double-throw switches and the ground pin; a PTC thermistor or a power resistor is connected in series between the first free end of the Mth single-pole double-throw switch of all 2N-2 single-pole double-throw switches and the ground pin, or a PTC thermistor or a power resistor is connected in series between the first free end of the M+1 single-pole double-throw switch and the battery positive connection terminal of the Nth charging level, wherein M is an even number less than 2N-2.

8. The battery charger of claim 6, wherein, The switch assembly further comprises a first additional single-pole double-throw switch, which is configured to synchronously switch the connection state between the fixed end and the free end with all 2N-2 single-pole double-throw switches; The fixed terminal of the first additional single-pole double-throw switch is connected to the first control module, one of the first free terminal and the second free terminal of the first additional single-pole double-throw switch is connected to the battery positive connection terminal of the Nth charging potential, and the other of the first free terminal and the second free terminal of the first additional single-pole double-throw switch is connected to the battery negative connection terminal of the first charging potential.

9. The battery charger of claim 8, wherein, The switch assembly further comprises a second additional single-pole double-throw switch, and the second additional single-pole double-throw switch is configured to synchronously switch the connection states of the fixed terminal and the free terminal with all 2N-2 single-pole double-throw switches. The fixed terminal of the second additional single-pole double-throw switch is connected to the first control module, one of the first free terminal and the second free terminal of the second additional single-pole double-throw switch is connected to the battery positive connection terminal of the Nth charging potential, and the other of the first free terminal and the second free terminal of the second additional single-pole double-throw switch is connected to the battery negative connection terminal of the first charging potential.

10. The battery charger of claim 1, wherein, The charging interface is configured as a Type-C interface, the charging positive pin is a VBUS pin of the Type-C interface, and CC1 and CC2 pins of the Type-C interface are connected to the first control module.

11. The battery charger of claim 1, wherein, The power pin of the first control module is connected to the charging positive pin and the battery positive connection terminal of the Nth charging potential.

12. The battery charger of claim 11, wherein, The battery charger further comprises a first voltage stabilizing module, the first voltage stabilizing module comprises a first voltage stabilizing module input end and a first voltage stabilizing module output end, and the first voltage stabilizing module is configured to output a direct current voltage signal with a constant voltage value at the first voltage stabilizing module output end when a high-level signal is input at the first voltage stabilizing module input end. The battery positive connection terminal of the Nth charging potential and the charging positive pin are connected to the first voltage stabilizing module input end, and the power pin of the first control module is connected to the first voltage stabilizing module output end.

13. The battery charger of claim 12, wherein, The battery charger further comprises: a first diode, a positive electrode of the first diode is connected to the battery positive connection terminal of the Nth charging potential, and a negative electrode of the first diode is connected to the first voltage stabilizing module input end; and a second diode, a positive electrode of the second diode is connected to the charging positive pin, and a negative electrode of the second diode is connected to the first voltage stabilizing module input end.

14. The battery charger of claim 12, wherein, The battery charger further comprises: a first indicator lamp, a first end of the first indicator lamp is connected to the first control module, and a second end of the first indicator lamp is connected to the first voltage stabilizing module output end; and a second indicator lamp, a first end of the second indicator lamp is connected to the first control module, and a second end of the second indicator lamp is connected to the first voltage stabilizing module output end.

15. The battery charger according to claim 14, wherein the first indicator lamp is configured as a first light-emitting diode, the first end of the first indicator lamp is a positive electrode of the first light-emitting diode, and the second end of the first indicator lamp is a negative electrode of the first light-emitting diode; and / or The second indicator light is configured as a second light-emitting diode, a first end of the second indicator light is an anode of the second light-emitting diode, and a second end of the second indicator light is a cathode of the second light-emitting diode.

16. The battery charger of any one of claims 1 to 15, wherein, The first control module is configured to, in the first state, detect a voltage Up of at least one of the N battery positive connection terminals, and when the voltage Up is lower than a preset voltage threshold, send an off signal to the switch circuit control end, so that the circuit between the first end of the switch circuit and the second end of the switch circuit is disconnected.

17. The battery charger of claim 16, wherein, The charging battery is a lithium rechargeable battery; and / or The preset voltage threshold is 2.8 to 4.3 V.

Images