A method and lighting device compatible with series connection of batteries with different numbers of cells

Abstract

The present invention proposes a method and lighting device compatible with different numbers of batteries connected in series, including: obtaining the voltage of the battery at startup; calculating the number of batteries currently connected in series according to the obtained voltage; obtaining the real-time voltage of the battery; calculating the battery power according to the real-time voltage and the number of batteries; when the calculated battery power is 0, controlling the battery to stop supplying power. The method and lighting device compatible with different numbers of batteries connected in series proposed by the present invention can prevent one or any number of batteries connected in series from over-discharging, and can make the LED work at a constant current when one or any number of batteries connected in series are supplying power, keeping the brightness unchanged, so that consumers can choose any number of batteries to supply power according to their own endurance requirements, providing convenience for consumers, strong practicality, and saving social resources.

Description

Technical Field

[0001] The present invention relates to the field of lighting technology, and in particular to a method and a lighting device that are compatible with connecting batteries of different numbers in series. Background Art

[0002] Over-discharging of batteries may damage the active materials in the battery electrodes and cause them to lose their ability to react, which may render the batteries unusable. Therefore, lighting devices on the market generally have a battery protection mechanism to prevent over-discharging of batteries. However, lighting devices on the market, such as flashlights, can usually only prevent over-discharging of batteries with a fixed number of cells, so they can only be powered by batteries with a fixed number of cells. However, in different usage scenarios, consumers may have different requirements for the battery life of lighting devices. Therefore, consumers usually need to purchase multiple lighting devices with different battery cell counts to adapt to usage scenarios with different battery life requirements, which brings inconvenience to consumers and wastes social resources. Summary of the invention

[0003] The main technical problem solved by the present invention is to provide a method and a lighting device compatible with batteries with different numbers of cells connected in series, which can prevent over-discharge of one or any number of batteries connected in series, so that consumers can choose any number of batteries for power supply according to their own battery life requirements.

[0004] According to the first aspect, an embodiment provides a method for connecting batteries with different numbers of cells in series, comprising:

[0005] Get the battery voltage at startup;

[0006] Calculate the number of battery cells currently connected in series according to the obtained voltage;

[0007] Get the real-time voltage of the battery;

[0008] Calculate the battery power according to the real-time voltage and number of battery cells;

[0009] When the calculated battery power is 0, the battery is controlled to stop supplying power.

[0010] In one possible implementation, the method for being compatible with series connection of batteries with different numbers of cells further includes: controlling the display of the calculated battery power.

[0011] In one possible implementation, the method for being compatible with series connection of batteries with different numbers of cells further includes:

[0012] Calculate a preset duty cycle of the PWM signal according to the calculated number of battery cells;

[0013] Controlling the output duty cycle of the PWM signal to be the preset duty cycle to drive the LED;

[0014] Get real-time working current;

[0015] Comparing the real-time working current with a preset working current to obtain a comparison result;

[0016] The duty cycle of the current PWM signal is adjusted according to the comparison result so that the real-time working current is equal to the preset working current.

[0017] In one possible implementation manner, adjusting the duty cycle of the current PWM signal according to the comparison result so that the real-time operating current is equal to the preset operating current includes:

[0018] When the comparison result is that the real-time working current is less than the preset working current, the duty cycle of the current PWM signal is adjusted stepwise in a first direction so that the real-time working current is equal to the preset working current;

[0019] When the comparison result is that the real-time operating current is greater than the preset operating current, the duty cycle of the current PWM signal is adjusted step by step in the second direction so that the real-time operating current is equal to the preset operating current.

[0020] In one possible implementation manner, the preset operating current is a maximum driving current of the LED.

[0021] According to the second aspect, an embodiment provides a lighting device compatible with batteries with different numbers of cells connected in series, comprising:

[0022] LED, for emitting light;

[0023] A battery connection port, used to connect one or more batteries connected in series;

[0024] A sampling module, connected to the battery connection port, for sampling the battery voltage and outputting the sampled voltage;

[0025] The control module is connected to the sampling module, and is used to obtain the sampled voltage at startup, and calculate the number of battery cells currently connected in series according to the sampled voltage at startup; obtain the real-time sampled voltage, calculate the real-time voltage of the battery according to the real-time sampled voltage, and calculate the battery power according to the real-time voltage of the battery and the number of battery cells; and when the calculated battery power is 0, control the battery to stop supplying power; and

[0026] The driving module is used to provide current to the LED.

[0027] In one possible implementation, the lighting device compatible with batteries with different numbers of cells connected in series further includes:

[0028] The power indicator module is connected to the control module and is used to display the power level of the battery.

[0029] In one possible implementation, the control module is further configured to calculate a preset duty cycle of the PWM signal according to the calculated number of battery cells, and output a PWM signal having a duty cycle equal to the preset duty cycle;

[0030] And used to obtain a real-time working current, compare the real-time working current with a preset working current to obtain a comparison result, and adjust the duty cycle of the current PWM signal according to the comparison result so that the driving module provides current to the LED according to the duty cycle of the PWM signal, so that the real-time working current is equal to the preset working current.

[0031] In one possible implementation, the control module adjusts the duty cycle of the current PWM signal according to the comparison result, including:

[0032] When the comparison result is that the real-time working current is less than the preset working current, the control module stepwise adjusts the duty cycle of the current PWM signal in a first direction so that the real-time working current is equal to the preset working current;

[0033] When the comparison result is that the real-time working current is greater than the preset working current, the control module stepwise adjusts the duty cycle of the current PWM signal in a second direction so that the real-time working current is equal to the preset working current.

[0034] In one possible implementation manner, the preset operating current is a maximum driving current of the LED.

[0035] The implementation of the embodiments of the present invention has the following beneficial effects:

[0036] According to the above-mentioned method and lighting device compatible with different numbers of batteries connected in series, the voltage of the battery at startup is first obtained, and the number of batteries currently connected in series is calculated according to the obtained voltage to obtain the real-time voltage of the battery; then the battery power is calculated according to the real-time voltage and the number of batteries; when the calculated battery power is 0, the battery is controlled to stop supplying power. In addition, by adjusting the duty cycle of the PWM signal, the driving module provides current to the LED according to the duty cycle of the PWM signal, so that the real-time working current is equal to a preset working current. Therefore, the present invention can prevent one or any number of batteries connected in series from over-discharging, and can make the LED work at a constant current when powered by one or any number of batteries connected in series, so as to keep the brightness unchanged, so that consumers can choose any number of batteries to supply power according to their own endurance requirements, which provides convenience for consumers, is highly practical, and saves social resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a step-down driving circuit using an NMOS tube in the prior art;

[0038] Figure 2It is a step-down driving circuit using a PMOS tube in the prior art;

[0039] Figure 3 The structural frame of the lighting device of the present invention that is compatible with batteries with different numbers of cells connected in series in one embodiment is as follows: Figure 1 ;

[0040] Figure 4 A structural cross-sectional view of a lighting device compatible with different numbers of batteries connected in series in one embodiment of the present invention;

[0041] Figure 5 The structural frame of the lighting device of the present invention that is compatible with batteries with different numbers of cells connected in series in one embodiment is as follows: Figure 2 ;

[0042] Figure 6 The structural frame of the lighting device of the present invention that is compatible with batteries with different numbers of cells connected in series in one embodiment is as follows: Figure 3 ;

[0043] Figure 7 A schematic diagram of a method for connecting batteries of different numbers in series according to the present invention in one embodiment Figure 1 ;

[0044] Figure 8 A schematic diagram of a method for connecting batteries of different numbers in series according to the present invention in one embodiment Figure 2 ;

[0045] Fig. 9 A schematic diagram of a method for connecting batteries of different numbers in series according to the present invention in one embodiment Figure 3 ;

[0046] Fig.10 A schematic diagram of a method for connecting batteries of different numbers in series according to the present invention in one embodiment Figure 4 . DETAILED DESCRIPTION

[0047] The present invention is further described in detail below by specific embodiments in conjunction with the accompanying drawings. Wherein similar elements in different embodiments adopt associated similar element numbers. In the following embodiments, many detailed descriptions are for making the present application better understood. However, those skilled in the art can easily recognize that some features can be omitted in different situations, or can be replaced by other elements, materials, methods. In some cases, some operations related to the present application are not shown or described in the specification, this is to avoid the core part of the present application being overwhelmed by too much description, and for those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations according to the description in the specification and the general technical knowledge in the art.

[0048] In addition, the features, operations or characteristics described in the specification can be combined in any appropriate manner to form various implementations. At the same time, the steps or actions in the method description can also be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for the purpose of clearly describing a certain embodiment and are not meant to be a required sequence, unless otherwise specified that a certain sequence must be followed.

[0049] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" mentioned in this application, unless otherwise specified, includes direct and indirect connections.

[0050] The LED drive circuit can be a buck drive circuit using an NMOS tube or a buck drive circuit using a PMOS tube. Figure 1 , Figure 1 This is a step-down drive circuit using an NMOS tube in the prior art. In this type of drive circuit, the change in the real-time operating current of the LED is proportional to the change in the duty cycle of the PWM signal, that is, the real-time operating current of the LED will increase as the duty cycle of the PWM signal increases, and the real-time operating current of the LED will decrease as the duty cycle of the PWM signal decreases. Please refer to Figure 2 , Figure 2 It is a step-down drive circuit using a PMOS tube in the prior art. In this type of drive circuit, the change of the real-time working current of the LED is inversely proportional to the change of the duty cycle of the PWM signal, that is, the real-time working current of the LED will decrease as the duty cycle of the PWM signal increases, and the real-time working current of the LED will increase as the duty cycle of the PWM signal decreases. The working principles of the two types of drive circuits are well-known technologies in the art and will not be repeated here.

[0051] In order to solve the problem that existing lighting devices are not compatible with over-discharge protection of batteries with different numbers of cells connected in series, it is necessary to calculate the battery power. When the battery power is 0, the battery can be controlled to stop supplying power to prevent over-discharge. However, batteries with different numbers of cells connected in series have different voltages, and the calculation method of power is also different. Therefore, the number of cells currently connected in series must be calculated first, and the battery power is calculated based on the real-time voltage and number of cells.

[0052] Embodiment 1:

[0053] Please refer to Figure 3In one embodiment, a lighting device compatible with batteries of different numbers connected in series includes an LED 101, a battery connection port 102, a sampling module 103, a control module 104 and a driving module 105. Each module is described in detail below.

[0054] The LED 101 is connected to the driving module 105 for emitting light.

[0055] The battery connection port 102 includes a first terminal and a second terminal for connecting one or more batteries connected in series.

[0056] Please refer to Figure 4 , Figure 4 In order to be compatible with a structural cross-sectional diagram of a lighting device having different numbers of batteries connected in series in one embodiment, the following uses the cross-sectional diagram as an example to explain in detail how the battery connection port 102 is connected to one or more batteries connected in series for power supply.

[0057] It should be noted that the batteries mentioned in this embodiment all have a first pole and a second pole. When the first pole of the battery is a positive pole, the second pole of the battery is a negative pole; conversely, when the first pole of the battery is a negative pole, the second pole of the battery is a positive pole.

[0058] Depend on Figure 4 It can be seen that the lighting device compatible with different numbers of batteries connected in series in some embodiments includes a lamp holder 100, a battery compartment 200 and an extension component 300, and each module is specifically described below.

[0059] The lamp holder 100 has a connection end and is provided with an LED 101 and a driving circuit for driving the LED 101 . The driving circuit includes a first terminal and a second terminal for receiving power supplied by a battery.

[0060] Specifically, the driving circuit includes the battery connection port 102, the sampling module 103, the control module 104 and the driving module 105. The first terminal of the driving circuit is the first terminal of the battery connection port 102, and the second terminal of the driving circuit is the second terminal of the battery connection port 102.

[0061] The battery compartment 200 is used to place one battery or multiple batteries connected in series. The battery compartment 200 has a connection end and a tail end. The connection end of the battery compartment 200 is detachably connected to the connection end of the lamp holder 100. When the battery compartment 200 is connected to the lamp holder 100, the first pole of the battery near the connection end in the battery compartment 200 can be electrically connected to the first terminal of the battery connection port 102; the tail end of the battery compartment 200 is provided with an electrical connection terminal for contacting the second pole of the battery near the tail end in the battery compartment 200 to electrically connect the second pole of the battery to the second terminal of the battery connection port 102.

[0062] The extension component 300 is used to place one battery or multiple batteries connected in series. One end of the extension component 300 can be detachably connected to the connection end of the lamp holder 100, and the other end can be detachably connected to the connection end of the battery compartment 200. When the extension component 300 is connected to the connection end of the lamp holder 100 and the connection end of the battery compartment 200, the first pole of the battery in the extension component 300 near the connection end of the lamp holder 100 can be electrically connected to the first terminal of the battery connection port 102, and the second pole of the battery in the extension component 300 near the connection end of the battery compartment 200 can be electrically connected to the first pole of the battery in the battery compartment 200 near the connection end.

[0063] In some embodiments, the extension component 300 includes at least one extension bin 301, each of which is used to place one battery or multiple batteries connected in series. The extension bins 301 each have a first connection end and a second connection end. The first connection end of the extension bin 301 can be detachably connected to the connection end of the lamp holder 100, and the second connection end of the extension bin 301 can be detachably connected to the connection end of the battery compartment 200. When the first connection end of the extension bin 301 is connected to the connection end of the lamp holder 100, the first pole of the battery in the extension bin 301 near the first connection end can be electrically connected to the first terminal of the battery connection port 102; when the second connection end of the extension bin 301 is connected to the connection end of the battery compartment 200, the second pole of the battery in the extension bin 301 near the second connection end can be electrically connected to the first pole of the battery in the battery compartment 200 near the connection end.

[0064] When the extension component 300 includes two or more extension compartments 301, the first end of any extension compartment 301 and the second end of another extension compartment 301 can be detachably connected; when two extension compartments 301 are connected, the second pole of the battery near the second connection end in one of the extension compartments 301 can be electrically connected to the first pole of the battery near the first connection end in the other extension compartment 301.

[0065] Therefore, when using the lighting device compatible with different numbers of batteries connected in series in this embodiment, the number of batteries connected in series can be changed according to whether the extension component 300 is used and the number of extension compartments 301 in the extension component 300 is changed.

[0066] The above is an explanation of how to accommodate and place a variable number of batteries from the perspective of mechanical structure. The following will continue to explain the lighting device that is compatible with different numbers of batteries connected in series.

[0067] The sampling module 103 is connected to the battery connection port 102 and is used for sampling the battery voltage and outputting the sampled voltage to the control module 104 .

[0068] The control module 104 is used to obtain the sampled voltage at startup from the sampling module 103 , and calculate the number of battery cells currently connected in series according to the sampled voltage at startup.

[0069] In some embodiments, the control module 104 may be a microcontroller such as a single chip microcomputer or an MCU such as an FPGA. After one or any number of batteries in series are connected to the battery connection port 102, the lighting device compatible with different numbers of batteries in series is started. The control module 104 may first set a battery number judgment time. During this time, the control module 104 shields the response and interaction of other functions except the battery number judgment, calculates the battery voltage at startup through the sampled voltage output by the sampling module 103, and calculates the number of batteries in series according to the battery voltage at startup.

[0070] Let's take the example of using two lithium batteries with an operating voltage of 3 to 4.24V to further explain the calculation method of the number of battery cells. Assuming that the voltage of the battery at startup is 7.2V, combined with the operating voltage range of the lithium battery used of 3 to 4.24V, it can be concluded that the relationship between the number of battery cells at this time satisfies 7.2 / 4.24≤Number of battery cells≤7.2 / 3, so it can be determined that the number of battery cells is 2.

[0071] The control module 104 is also used to obtain the real-time sampled voltage, calculate the real-time voltage of the battery according to the real-time sampled voltage, and then calculate the battery power according to the real-time voltage of the battery and the number of battery cells.

[0072] Let's take a lithium battery with an operating voltage of 3 to 4.24V as an example to further explain the calculation method of battery power. Please refer to the following table, which shows the relationship between the voltage and power percentage of n lithium batteries with an operating voltage range of 3 to 4.24V.

[0073] Power 0％ 5％ 10％ 15％ 20％ 25％ 30％ 35％ 40％ 45％ Battery voltage (V) 3n 3.518n 3.541n 3.579n 3.622n 3.643n 3.656n 3.671n 3.688n 3.708n Power 50％ 55％ 60％ 65％ 70％ 75％ 80％ 85％ 90％ 95％ Battery voltage (V) 3.735n 3.77n 3.807n 3.85n 3.899n 3.952n 4.006n 4.064n 4.126n 4.192n Power 100％ - - - - - - - - - Battery voltage (V) 4.201n - - - - - - - - -

[0074] When the real-time voltage of the battery is U0 and the number of battery cells is n, the percentage relationship between the voltage and the power of n lithium batteries with an operating voltage of 3 to 4.24V is calculated according to the number of battery cells n, and then the battery voltage coefficient range where the real-time voltage U0 of the battery is located is determined. The battery power can be calculated according to the determined battery voltage coefficient range; if a more accurate battery power is required, it can be calculated using the following formula:

[0075] E=Es+(U0-Us) / ((Ue-Us) / 5); wherein E is the battery power, Es is the initial value of the battery power range, U0 is the real-time voltage of the battery, Us is the initial value of the battery voltage coefficient range, and Ue is the end value of the battery voltage coefficient range.

[0076] For example, assuming that the real-time voltage of the battery is 7.26V and the number of battery cells is 2, according to Table 2, 3.622*2V<7.26V<3.643*2V, it can be concluded that the battery voltage coefficient range is 3.622*2V~3.643*2V, and the power corresponding to 3.622*2V and 3.643*2V are 20% and 25% respectively, so the battery power range is 20%~25%. From E=20+(7.26-3.622*2) / ((3.643*2-3.622*2) / 5)=21.9, it can be concluded that the specific battery power is 21.9%.

[0077] The control module 104 is also used to control the battery to stop supplying power when the calculated battery power is 0. When the battery power is 0, the corresponding battery voltage is the cut-off voltage of the battery operation. At this time, controlling the battery to stop supplying power can prevent the battery from over-discharging.

[0078] In some embodiments, the control module 104 can also be used to calculate the preset duty cycle of the PWM signal according to the calculated number of battery cells, and output the PWM signal with the preset duty cycle to the driving module 105. In some embodiments, the preset duty cycle can be a minimum duty cycle or a maximum duty cycle. It should be noted that if the driving circuit is a buck driving circuit using an NMOS tube, the preset duty cycle can be the minimum duty cycle; if the driving circuit is a buck driving circuit using a PMOS tube, the preset duty cycle can be the maximum duty cycle.

[0079] In some embodiments, the calculation formula of the minimum duty cycle of the PWM signal may be as follows:

[0080] Dmin=Uled / (U1*n); wherein Dmin is the minimum duty cycle of the PWM signal, Uled is the maximum driving voltage of LED 101, U1 is the maximum operating voltage of the battery, and n is the number of battery cells.

[0081] In some embodiments, the maximum duty cycle of the PWM signal may be calculated as follows:

[0082] Dmax=Uled / (U2*n); wherein Dmax is the maximum duty cycle of the PWM signal, Uled is the maximum driving voltage of LED 101, U2 is the minimum operating voltage of the battery, and n is the number of battery cells.

[0083] In some embodiments, the control module 104 can also be used to obtain the real-time working current, compare the real-time working current with a preset working current, obtain a comparison result, and adjust the duty cycle of the current PWM signal according to the comparison result so that the driving module 105 provides a current to the LED according to the duty cycle of the PWM signal, so that the real-time working current is equal to the preset working current. In some embodiments, the preset working current can be the maximum driving current of the LED 101.

[0084] In some embodiments, when the comparison result is that the real-time working current is less than the preset working current, the control module 104 can step-by-step adjust the duty cycle of the current PWM signal in the first direction so that the real-time working current is equal to the preset working current. It should be noted that if the drive circuit is a buck drive circuit using an NMOS tube, step-by-step adjusting the duty cycle of the current PWM signal in the first direction is to step-by-step increase the duty cycle of the current PWM signal; if the drive circuit is a buck drive circuit using a PMOS tube, step-by-step adjusting the duty cycle of the current PWM signal in the first direction is to step-by-step reduce the duty cycle of the current PWM signal. When the comparison result is that the real-time working current is greater than the preset working current, the control module 104 can step-by-step adjust the duty cycle of the current PWM signal in the second direction so that the real-time working current is equal to the preset working current. It should be noted that, if the driving circuit is a buck-type driving circuit using an NMOS tube, step-by-step adjusting the duty cycle of the current PWM signal in the second direction is to step-by-step reduce the duty cycle of the current PWM signal; if the driving circuit is a buck-type driving circuit using a PMOS tube, step-by-step adjusting the duty cycle of the current PWM signal in the second direction is to step-by-step increase the duty cycle of the current PWM signal.

[0085] In some embodiments, in order to ensure the safety of LED 101 and other circuit elements during the duty cycle adjustment process, if the driving circuit is a buck driving circuit using an NMOS tube, when the control module 104 increases the duty cycle of the current PWM signal in a step-by-step manner, it can be increased to the above-mentioned maximum duty cycle at most; if the driving circuit is a buck driving circuit using a PMOS tube, when the control module 104 decreases the duty cycle of the current PWM signal in a step-by-step manner, it can be decreased to the above-mentioned minimum duty cycle at least.

[0086] The driving module 105 is used to provide current to the LED to drive the LED to emit light.

[0087] Please refer to Figure 5 In some embodiments, the lighting device compatible with different numbers of batteries connected in series may further include a power indicator module 106 connected to the control module 104 to display the power of the battery. In some embodiments, the power indicator module 106 may display the power of the battery using an LED light and an LCD screen.

[0088] Please refer to Figure 6 In some embodiments, the lighting device compatible with different numbers of batteries connected in series may further include an external control input module 107 connected to the control module 104 to provide an external trigger signal. In some embodiments, the external control input module 107 may be a physical button, a touch button, or a Hall magnetic induction button.

[0089] The following is an explanation of the overall workflow of a lighting device that is compatible with batteries of different numbers connected in series.

[0090] It can be seen that in one example, when one or more batteries connected in series are connected to the battery connection port 102, the lighting device compatible with different numbers of batteries connected in series is started, and the control module 104 first sets a battery number judgment time. During this time, the control module 104 shields the response and interaction of other functions except the battery number judgment, and calculates the battery voltage at startup through the sampled voltage output by the sampling module 103, calculates the number of batteries connected in series according to the battery voltage at startup, and calculates the preset duty cycle of the PWM signal according to the number of batteries; when the control module 104 receives the external trigger signal input by the external control input module 107, the control module 104 outputs a duty cycle of The PWM signal with a preset duty cycle is sent to the driving module 105, and the driving module 105 provides current to the LED 101 according to the duty cycle of the PWM signal; the control module 104 obtains the real-time working current of the LED 101, compares the real-time working current with a preset working current, obtains the comparison result, and adjusts the duty cycle of the current PWM signal according to the comparison result so that the real-time working current is equal to the preset working current; the control module 104 also obtains the real-time voltage of the battery, calculates the battery power according to the real-time voltage of the battery and the number of battery cells, and displays the battery power through the power indicator module 106; when the calculated battery power is 0, the control module 104 controls the battery to stop supplying power. Therefore, when using the lighting device compatible with different numbers of batteries connected in series in this embodiment, connecting one or any number of batteries connected in series for power supply can prevent the battery from over-discharging, and the LEDs finally work at a constant current to keep the brightness unchanged.

[0091] In addition, when using the lighting device in this embodiment that is compatible with different numbers of batteries connected in series, the number of batteries connected in series can be changed according to whether the extension component 300 is used and the number of extension compartments 301 in the extension component 300 is changed. This allows consumers to choose any number of batteries for power supply according to their own battery life requirements. There is no need to purchase multiple lighting devices with different numbers of batteries to adapt to usage scenarios with different battery life requirements. This provides convenience for consumers, is highly practical, and saves social resources.

[0092] Embodiment 2:

[0093] Please refer to Figure 7 In one embodiment, a method for connecting batteries with different numbers of cells in series includes the following steps:

[0094] Step S010: Obtain the battery voltage during startup.

[0095] Step S020: Calculate the number of battery cells currently connected in series according to the acquired voltage.

[0096] Let's take the example of using two lithium batteries with an operating voltage of 3 to 4.24V to further explain the calculation method of the number of battery cells. Assuming that the voltage of the battery at startup is 7.2V, combined with the operating voltage range of the lithium battery used is 3 to 4.24V, it can be concluded that the relationship between the number of battery cells at this time satisfies 7.2 / 4.24≤Number of battery cells≤7.2 / 3, so it can be determined that the number of battery cells is 2.

[0097] Step S030: Obtain the real-time voltage of the battery.

[0098] Step S040: Calculate the battery power according to the real-time voltage of the battery and the number of battery cells.

[0099] Let's take a lithium battery with an operating voltage of 3 to 4.24V as an example to further explain the calculation method of battery power. Please refer to the following table, which shows the relationship between the voltage and power percentage of n lithium batteries with an operating voltage range of 3 to 4.24V.

[0100] Power 0％ 5％ 10％ 15％ 20％ 25％ 30％ 35％ 40％ 45％ Battery voltage (V) 3n 3.518n 3.541n 3.579n 3.622n 3.643n 3.656n 3.671n 3.688n 3.708n Power 50％ 55％ 60％ 65％ 70％ 75％ 80％ 85％ 90％ 95％ Battery voltage (V) 3.735n 3.77n 3.807n 3.85n 3.899n 3.952n 4.006n 4.064n 4.126n 4.192n Power 100％ - - - - - - - - - Battery voltage (V) 4.201n - - - - - - - - -

[0101] When the real-time voltage of the battery is U0 and the number of battery cells is n, the percentage relationship between the voltage and the power of n lithium batteries with an operating voltage of 3 to 4.24V is calculated according to the number of battery cells n, and then the battery voltage coefficient range where the real-time voltage U0 of the battery is located is determined. The battery power can be calculated according to the determined battery voltage coefficient range; if a more accurate battery power is required, it can be calculated using the following formula:

[0102] E=Es+(U0-Us) / ((Ue-Us) / 5); wherein E is the battery power, Es is the initial value of the battery power range, U0 is the real-time voltage of the battery, Us is the initial value of the battery voltage coefficient range, and Ue is the end value of the battery voltage coefficient range.

[0103] For example, assuming that the real-time voltage of the battery is 7.26V and the number of battery cells is 2, according to Table 2, 3.622*2V<7.26V<3.643*2V, it can be concluded that the battery voltage coefficient range is 3.622*2V~3.643*2V, and the power corresponding to 3.622*2V and 3.643*2V are 20% and 25% respectively, so the battery power range is 20%~25%. From E=20+(7.26-3.622*2) / ((3.643*2-3.622*2) / 5)=21.9, it can be concluded that the specific battery power is 21.9%.

[0104] Step S050: When the calculated battery power is 0, the battery is controlled to stop supplying power.

[0105] When the battery power is 0, the corresponding battery voltage is the cut-off voltage of the battery operation. At this time, controlling the battery to stop supplying power can prevent the battery from over-discharging.

[0106] It should be noted that step S030 is not limited to being executed only between step S020 and step S040, but may also be executed between step S010 and step S020, and the present invention does not make any specific limitation on this.

[0107] Please refer to Figure 8 In one embodiment, the method for being compatible with connecting batteries with different numbers of cells in series may further include the following steps:

[0108] Step S060: controlling the display of the calculated battery power.

[0109] Please refer to Fig. 9 In one embodiment, the method for being compatible with connecting batteries with different numbers of cells in series may further include the following steps:

[0110] Step S070: Calculate a preset duty cycle of the PWM signal according to the calculated number of battery cells.

[0111] In some embodiments, the preset duty cycle may be a minimum duty cycle or a maximum duty cycle. It should be noted that if the driving circuit is a buck driving circuit using an NMOS tube, the preset duty cycle may be a minimum duty cycle; if the driving circuit is a buck driving circuit using a PMOS tube, the preset duty cycle may be a maximum duty cycle.

[0112] In some embodiments, the calculation formula of the minimum duty cycle of the PWM signal may be as follows:

[0113] Dmin=Uled / (U1*n); wherein Dmin is the minimum duty cycle of the PWM signal, Uled is the maximum driving voltage of the LED, U1 is the maximum operating voltage of the battery, and n is the number of battery cells.

[0114] In some embodiments, the maximum duty cycle of the PWM signal may be calculated as follows:

[0115] Dmax=Uled / (U2*n); wherein Dmax is the maximum duty cycle of the PWM signal, Uled is the maximum driving voltage of LED 101, U2 is the minimum operating voltage of the battery, and n is the number of battery cells.

[0116] Step S080: Control the output duty cycle of the PWM signal to be a preset duty cycle to drive the LED.

[0117] Step S090: Obtain real-time working current.

[0118] Step S100: Compare the real-time working current with a preset working current to obtain a comparison result.

[0119] In some embodiments, the preset operating current may be a maximum driving current of the LED.

[0120] Step S110: adjusting the duty cycle of the current PWM signal according to the comparison result so that the real-time working current is equal to the preset working current.

[0121] It can be seen that when powered by one or any number of batteries connected in series, the LED can ultimately operate at a constant current to maintain constant brightness.

[0122] It should be noted that steps S070 to S110 are not limited to being executed only between step S020 and step S030, but may also be executed between step S030 and step S040, between step S040 and step S060, and between step 060 and step S050, and the present invention does not make any specific limitation on this.

[0123] For some examples, please refer to Fig.10 Step S110 adjusts the duty cycle of the current PWM signal according to the comparison result so that the real-time working current is equal to the preset working current, which may include the following steps:

[0124] Step S111: determine whether the real-time working current is less than the preset working current, if so, go to step S112; otherwise, go to step S113.

[0125] Step S112: stepwise adjust the duty cycle of the current PWM signal in a first direction so that the real-time working current is equal to the preset working current.

[0126] It should be noted that, if the driving circuit is a buck-type driving circuit using an NMOS tube, step-by-step adjusting the duty cycle of the current PWM signal in the first direction is to step-by-step increase the duty cycle of the current PWM signal; if the driving circuit is a buck-type driving circuit using a PMOS tube, step-by-step adjusting the duty cycle of the current PWM signal in the first direction is to step-by-step decrease the duty cycle of the current PWM signal.

[0127] Step S113: Determine whether the real-time working current is greater than the preset working current, if so, go to step S114. Otherwise, go to step S115.

[0128] Step S114: stepwise adjust the duty cycle of the current PWM signal in a second direction so that the real-time working current is equal to the preset working current.

[0129] It should be noted that, if the driving circuit is a buck-type driving circuit using an NMOS tube, step-by-step adjusting the duty cycle of the current PWM signal in the second direction is to step-by-step reduce the duty cycle of the current PWM signal; if the driving circuit is a buck-type driving circuit using a PMOS tube, step-by-step adjusting the duty cycle of the current PWM signal in the second direction is to step-by-step increase the duty cycle of the current PWM signal.

[0130] Step S075: Keep the duty cycle of the current PWM signal unchanged so that the LED maintains constant current operation.

[0131] In some embodiments, in order to ensure the safety of LEDs and other circuit elements during the duty cycle adjustment process, if the driving circuit is a step-down driving circuit using an NMOS tube, when the duty cycle of the current PWM signal is increased step by step, it can be increased to the above-mentioned maximum duty cycle at the maximum; if the driving circuit is a step-down driving circuit using a PMOS tube, when the duty cycle of the current PWM signal is reduced step by step, it can be reduced to the above-mentioned minimum duty cycle at the minimum.

[0132] The main workflow of the method compatible with different numbers of batteries connected in series is described below.

[0133] It can be seen that in some examples, when one or more batteries connected in series are used for power supply, the voltage of the battery at startup is first obtained, and the number of battery cells currently connected in series is calculated based on the obtained voltage; based on the calculated number of battery cells, the preset duty cycle of the PWM signal is calculated, and the output duty cycle is controlled to be a PWM signal with a preset duty cycle to drive the LED, and then the real-time working current is obtained, and the real-time working current is compared with a preset working current to obtain a comparison result, and the duty cycle of the current PWM signal is adjusted according to the comparison result so that the real-time working current is equal to the preset working current; and the real-time voltage of the battery is obtained, and the battery power is calculated based on the real-time voltage of the battery and the number of battery cells; when the calculated battery power is 0, the battery is controlled to stop supplying power. Therefore, when using the method of being compatible with batteries of different numbers connected in series in this embodiment, connecting one or any number of batteries connected in series for power supply can prevent the battery from over-discharging, and the LEDs ultimately operate at a constant current to maintain constant brightness, allowing consumers to choose any number of batteries for power supply according to their own battery life requirements, without having to purchase multiple lighting devices with different numbers of batteries to adapt to usage scenarios with different battery life requirements, providing convenience for consumers, strong practicality, and saving social resources.

[0134] The above specific examples are used to illustrate the present invention, which are only used to help understand the present invention and are not used to limit the present invention. For those skilled in the art to which the present invention belongs, some simple deductions, modifications or substitutions can be made according to the idea of ​​the present invention.

Claims

1. A method for connecting batteries with different numbers of cells in series, characterized in that: include: Get the battery voltage at startup; Calculate the number of battery cells currently connected in series according to the obtained voltage; Get the real-time voltage of the battery; Calculate the battery power according to the real-time voltage and number of battery cells; When the calculated battery power is 0, the battery is controlled to stop supplying power.

2. The method for connecting batteries of different numbers in series as claimed in claim 1, characterized in that: Also includes: Controls the display of the calculated battery charge.

3. The method for connecting batteries of different numbers in series as claimed in claim 1, characterized in that: Also includes: Calculate a preset duty cycle of the PWM signal according to the calculated number of battery cells; Controlling the output duty cycle of the PWM signal to be the preset duty cycle to drive the LED; Get real-time working current; Comparing the real-time working current with a preset working current to obtain a comparison result; The duty cycle of the current PWM signal is adjusted according to the comparison result so that the real-time working current is equal to the preset working current.

4. The method for connecting batteries of different numbers in series as claimed in claim 3, characterized in that: The step of adjusting the duty cycle of the current PWM signal according to the comparison result so that the real-time working current is equal to the preset working current includes: When the comparison result is that the real-time working current is less than the preset working current, the duty cycle of the current PWM signal is adjusted stepwise in a first direction so that the real-time working current is equal to the preset working current; When the comparison result is that the real-time operating current is greater than the preset operating current, the duty cycle of the current PWM signal is adjusted step by step in the second direction so that the real-time operating current is equal to the preset operating current.

5. The method for connecting batteries of different numbers in series as claimed in claim 3, characterized in that: The preset operating current is the maximum driving current of the LED.

6. A lighting device compatible with batteries of different numbers connected in series, characterized in that: include: LED, for emitting light; A battery connection port, used to connect one or more batteries connected in series; A sampling module, connected to the battery connection port, for sampling the battery voltage and outputting the sampled voltage; The control module is connected to the sampling module and is used to obtain the sampled voltage at startup and calculate the number of battery cells currently connected in series according to the sampled voltage at startup; obtain the real-time sampled voltage, calculate the real-time voltage of the battery according to the real-time sampled voltage, and calculate the battery power according to the real-time voltage of the battery and the number of battery cells; and for controlling the battery to stop supplying power when the calculated battery power level is 0; as well as The driving module is used to provide current to the LED.

7. The lighting device compatible with batteries of different numbers connected in series as claimed in claim 6, characterized in that: Also includes: The power indicator module is connected to the control module and is used to display the power level of the battery.

8. The lighting device compatible with batteries of different numbers connected in series as claimed in claim 6, characterized in that: The control module is further used to calculate a preset duty cycle of the PWM signal according to the calculated number of battery cells, and output a PWM signal with a duty cycle equal to the preset duty cycle; And used to obtain a real-time working current, compare the real-time working current with a preset working current to obtain a comparison result, and adjust the duty cycle of the current PWM signal according to the comparison result so that the driving module provides current to the LED according to the duty cycle of the PWM signal, so that the real-time working current is equal to the preset working current.

9. The lighting device compatible with batteries of different numbers connected in series as claimed in claim 8, characterized in that: The control module adjusts the duty cycle of the current PWM signal according to the comparison result, including: When the comparison result is that the real-time working current is less than the preset working current, the control module stepwise adjusts the duty cycle of the current PWM signal in a first direction so that the real-time working current is equal to the preset working current; When the comparison result is that the real-time working current is greater than the preset working current, the control module stepwise adjusts the duty cycle of the current PWM signal in a second direction so that the real-time working current is equal to the preset working current.

10. The lighting device compatible with batteries of different numbers connected in series as claimed in claim 8, characterized in that: The preset operating current is the maximum driving current of the LED.

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