A rechargeable lithium battery

Abstract

The utility model relates to battery technical field, concretely is a kind of rechargeable lithium battery function circuit, is composed of lithium battery charging part, lithium battery protection part, voltage stabilizing output part, electric quantity display part and lithium ion battery. In the charging process, electric energy enters through interface, first pass through TP4056 chip voltage reduction current limiting, then pass through WST8205A chip detection, control DW01 chip to lithium ion battery is charged. In the use process, on one hand, the electric energy in lithium ion battery first pass through WST8205A chip detection, control DW01 chip to AMS1117 chip discharges, AMS1117 chip will electric energy voltage reduction and output, according to the model of AMS1117 chip different can output different voltage to be compatible with electrical equipment. On the other hand, the residual electric quantity in lithium ion battery is detected in real time by HM1160 chip and is displayed. It is used to replace the use of nickel-chromium (nickel-hydrogen) battery and dry battery.

Description

Technical Field

[0001] This utility model belongs to the field of lithium battery technology and relates to a functional circuit for a rechargeable lithium battery. Background Technology

[0002] Batteries are a common type of electrical energy storage device in our lives, and they are ubiquitous, ranging from small items like remote controls and electronic watches to large items like cars and ships. They utilize highly reactive metal materials to form the anode and stable materials to form the cathode. Due to Coulomb forces, the anode material loses electrons and flows to the cathode, where it gains electrons. Inside the battery, anions from the cathode flow to the cations from the anode and combine with them, thus forming a circuit and generating electrical energy.

[0003] Once the chemical energy inside a battery is depleted, it becomes unusable, and the large-scale disposal of used batteries directly leads to environmental degradation. Therefore, the development of low-pollution rechargeable batteries is crucial, and rechargeable lithium battery technology possesses the following characteristics:

[0004] 1. High voltage: Lithium iron phosphate 3.2V, lithium manganese oxide 3.6V, lithium nickel oxide 3.6V, nickel-cobalt-aluminum ternary lithium 3.6V, nickel-cobalt-manganese ternary lithium 3.6V, lithium cobalt oxide 3.7V

[0005] 2. High energy density: 3-4 times that of nickel-cadmium batteries and 2-3 times that of nickel-metal hydride batteries.

[0006] 3. Long cycle life: Generally, it can reach 500 to 1000 cycles, while lithium iron phosphate batteries are special and can reach more than 2000 cycles.

[0007] 4. Environmentally friendly: Contains no cadmium, lead, mercury, etc., making it more environmentally friendly than lead-acid batteries and nickel-cadmium batteries, and it has no memory effect.

[0008] Based on these advantages, we see lithium batteries widely used in our lives, such as in electric vehicles, new energy vehicles, mobile phone batteries, and power banks. However, the high voltage of lithium batteries, while bringing convenience, is also a significant drawback. The batteries we use in daily life typically operate at 1.5V, reaching 3V only when two batteries are connected in series. Lithium batteries cannot directly discharge below 3V, meaning we cannot directly enjoy the convenience of lithium battery technology in devices that require 1.5V batteries.

[0009] Further observation of existing rechargeable batteries on the market reveals that the mainstream rechargeable batteries with a voltage of around 1.5V are currently nickel-cadmium or nickel-metal hydride rechargeable batteries, characterized by:

[0010] 1. The voltage is low, only 1.2V. The battery will not function properly when exposed to voltage-sensitive devices.

[0011] 2. Observing the discharge curves of ordinary non-rechargeable dry cell batteries and nickel-cadmium or nickel-metal hydride rechargeable batteries reveals that their performance is significantly lower than that of ordinary non-rechargeable dry cell batteries; the discharge curves show that their performance is only half that of ordinary non-rechargeable dry cell batteries.

[0012] 3. While more expensive, they are cheaper to use. The price of these batteries is approximately 1.25-2 times that of ordinary non-rechargeable dry cell batteries. Compared to ordinary non-rechargeable dry cell batteries, nickel-cadmium or nickel-metal hydride rechargeable batteries can be used multiple times.

[0013] 4. The battery has a "memory effect," meaning improper charging and discharging will significantly shorten its lifespan.

[0014] 5. Chromium in batteries pollutes the environment.

[0015] Based on the above, it is not difficult to see that these nickel-cadmium or nickel-metal hydride rechargeable batteries have many drawbacks, making them difficult to use on a wide scale. Utility Model Content

[0016] The purpose of this invention is to address the problems existing in the background technology by providing a functional circuit for a rechargeable lithium battery. In particular, it provides a multifunctional circuit capable of controlling the charging, discharging, protection, and power display of a rechargeable lithium battery, aiming to solve the 1.5V output problem of rechargeable lithium batteries and enabling the designed new battery to replace and surpass existing nickel-cadmium or nickel-metal hydride rechargeable batteries.

[0017] To solve the above-mentioned technical problems, this utility model patent is designed with four functional parts: lithium battery charging part, lithium battery protection part, voltage regulation output part, and power display part.

[0018] The lithium battery protection circuit is used to input electrical energy into the lithium battery or output electrical energy from the lithium battery. It includes a functional circuit composed of a DW01 chip and a WST8205A dual NMOS transistor.

[0019] The lithium battery charging circuit is used to input electrical energy into the lithium battery protection circuit. It includes a functional circuit consisting of a TP4056 charging chip and a charging interface.

[0020] The voltage regulation output section circuit is used to output the electrical energy of the lithium battery protection section circuit, and includes a functional circuit composed of an AMS1117 voltage regulation output chip.

[0021] The power display circuit is used to display the power level in the lithium battery, and includes a functional circuit composed of an HM1160 power display chip.

[0022] The rechargeable lithium battery used in this design is a conventional lithium-ion battery, characterized by the use of lithium cobalt oxide as the positive electrode material.

[0023] The beneficial effects of this invention are: it utilizes rechargeable lithium battery technology and incorporates four circuits—charging, discharging, protection, and power display—into the rechargeable lithium battery. The advantages of this approach are:

[0024] 1. This enables rechargeable lithium batteries to release electricity at three adjustable voltage levels: 1.5V, 3.3V, and up to 3V, replacing 1.2V nickel-cadmium or nickel-metal hydride rechargeable batteries and ordinary 1.5V dry cell batteries.

[0025] 2. The TP4056 charging IC is used. Since it has five functions, namely shutdown when not charging, pre-charging, constant current charging, constant voltage charging, and shutdown when charging is completed, it can achieve a more scientific charging of rechargeable lithium batteries.

[0026] 3. The DW01 rechargeable lithium battery protection IC is used. Compared with ordinary nickel-cadmium or nickel-metal hydride rechargeable batteries, it avoids damage to the battery caused by overcharging and over-discharging, and protects against battery short circuits to prevent spontaneous combustion or explosion caused by short circuits.

[0027] 4. It uses the AMS1117 voltage regulator chip, which can stabilize the output at three adjustable voltage levels: 1.5V, 3.3V, and 3V, thus avoiding damage to electrical equipment due to voltage fluctuations in the rechargeable lithium battery.

[0028] 5. The HM1160 power display IC is used, allowing users to intuitively see the remaining power of the rechargeable lithium battery during use, thus improving the user experience. Attached Figure Description

[0029] Figure 1 Overall structure diagram;

[0030] Figure 2 Complete circuit diagram;

[0031] Figure 3 Circuit diagram of the lithium battery charging section;

[0032] Figure 4 Circuit diagram of lithium battery protection section;

[0033] Figure 5 Circuit diagram of the regulated output section;

[0034] Figure 6 Circuit diagram of the power display section. Detailed Implementation

[0035] like Figure 1 and Figure 2 As shown, the hardware is divided into five parts, which are further subdivided into the following five parts: Figure 3 The lithium battery charging circuit shown is as follows: Figure 4 The lithium battery protection circuit shown Figure 5 The voltage regulator output circuit shown Figure 6 The circuit shown contains the power display section and a rechargeable lithium battery.

[0036] like Figure 3 As shown, the lithium battery charging section includes a TAPY C charging interface (which can be replaced with other types of interfaces, but the interface input voltage must not exceed 8V), a TP4056 charging IC, resistor R1 (0.4Ω), resistor R5 (between 0.82KΩ and 10.5KΩ, 0.82KΩ corresponds to the output of 120mA current to charge the rechargeable lithium battery, and 10.5KΩ corresponds to the output of 1300mA current to charge the rechargeable lithium battery), resistor R3 (1KΩ), resistor R4 (1KΩ), LED1 (red), LED2 (green), capacitor C1 (10UF), and capacitor C2 (10UF). The positive terminal of the Tapy C charging interface is connected in series with resistor R1 to VCC (pin 4) and CE (pin 8) of the TP4056 charging IC. The negative terminal of the Tapy C charging interface is directly connected to GND. The PROG (pin 2) terminal of the TP4056 charging IC is connected in series with resistor R5 and then grounded. Capacitor C1 is connected in parallel between VCC (pin 4) and GND of the TP4056 charging IC. Capacitor C2 is connected in parallel between B+ and GND of the battery. The CHRG# (pin 7) terminal of the TP4056 charging IC is connected in series with resistor R3, then with LED1, and then to VCC (pin 4). The STDBY# (pin 6) terminal of the TP4056 charging IC is connected in series with resistor R4, then with LED2, and then to VCC (pin 4). The BAT (pin 5) of the TP4056 charging IC is directly connected to the positive terminal of the rechargeable lithium battery, while the EP (pin 9) of the TP4056 charging IC is left floating.

[0037] The lithium battery charging circuit was designed with reference to the TP4056 charging IC datasheet. Since the TP4056 charging IC is specifically designed for linear charging of single rechargeable lithium batteries, this design fully utilizes its five functions: ① shutdown when not charging, pre-charging, constant current charging, constant voltage charging, and shutdown upon completion of charging. This enables a more scientific charging of rechargeable lithium batteries. ② It provides excellent charging protection for rechargeable lithium batteries during charging. This design perfectly utilizes the TP4056 charging IC, enabling it to provide safe charging functionality for this design.

[0038] like Figure 4 As shown, the lithium battery protection section consists of a DW01 lithium battery protection IC, a WST8205A dual NMOS transistor, resistor R2 (100Ω), resistor R6 (1KΩ), and capacitor C3 (0.1UF). The 0D (pin 1) of the DW01 lithium battery protection IC is directly connected to the G2 (pin 4) of the WST8205A dual NMOS transistor. The CS (pin 2) of the DW01 lithium battery protection IC is connected to GND after series with resistor R6. The OC (pin 3) of the DW01 lithium battery protection IC is directly connected to the G1 (pin 6) of the WST8205A dual NMOS transistor. The TD (pin 4) of the DW01 lithium battery protection IC is left floating. The VCC (pin 5) of the DW01 lithium battery protection IC is connected to the G1 (pin 6) of the WST8205A dual NMOS transistor after series with resistor R2 (100Ω). 2 is directly connected to the positive terminal of the rechargeable lithium battery. The GND (pin 6) of the DW01 lithium battery protection IC is connected to GND. The capacitor C3 is connected in parallel to the VCC (pin 5) of the DW01 lithium battery protection IC and the negative terminal of the rechargeable lithium battery. The S1 (pin 1) of the WST8205A dual NMOS transistor is directly connected to the negative terminal of the rechargeable lithium battery. The S2 (pin 3) of the WST8205A dual NMOS transistor is connected to GND. The D (pins 2 and 5) of the WST8205A dual NMOS transistor are left floating.

[0039] The lithium battery protection circuit was designed with reference to the datasheets of the DW01 lithium battery protection IC and the WST8205A dual NMOS transistor. Since the DW01 lithium battery protection IC is a high-precision single-cell rechargeable lithium battery protection IC, it possesses comprehensive overvoltage charging protection, overvoltage discharging protection, overcurrent discharging / battery short-circuit protection, and charging detection functions. This design fully utilizes these advantages to achieve: ① Dual overcharge protection (the first layer comes from the TP4056 charging IC's built-in charging completion shutdown function, and the second layer comes from the DW01 lithium battery protection IC's overvoltage charging protection), effectively preventing damage and danger to the rechargeable lithium battery caused by overcharging; ② Overvoltage and overcurrent discharging protection, effectively preventing damage to the rechargeable lithium battery due to over-discharging and abnormal discharging; ③ Short-circuit protection, preventing the rechargeable lithium battery in this design from spontaneous combustion or explosion due to short circuits.

[0040] like Figure 5 As shown, the voltage regulation output section consists of an AMS1117 voltage regulator chip (specifically, three models: AMS1117-ADJ, AMS1117-3.3, and AMS1117-1.5, used for variable output up to 3V, 3V output, and 1.5V output respectively) and a capacitor C4 (10uF). The GND (pin 1) of the AMS1117 voltage regulator chip is connected to GND, the Vout (pins 2 and 4) of the AMS1117 voltage regulator chip is brought out for output, the Vin (pin 3) of the AMS1117 voltage regulator chip is connected to the positive terminal of the rechargeable lithium battery, and the capacitor C4 is connected in parallel between the Vout (pins 2 and 4) of the AMS1117 voltage regulator chip and GND.

[0041] The voltage regulation output circuit was designed with reference to the AMS1117 voltage regulator chip datasheet. Since the AMS1117 is a three-terminal linear regulator with a maximum output of 1A, it can provide a stable voltage output. Although the AMS1117 voltage regulator chip has various output voltage forms, this design only uses three types: AMS1117-ADJ, AMS1117-3.3, and AMS1117-1.5, to simulate the output of a 1.5V battery, a 3V battery (two ordinary dry cell batteries in series), and batteries with voltages within 0-3V (1.2V, 1.8V, etc., batteries used in special equipment). This design achieves a near-perfect discharge curve. With ordinary dry cell batteries and NiCd or NiMH rechargeable batteries, changes in charge lead to changes in voltage. When the voltage is lower than the voltage required by the device, although the battery is not completely depleted, the device will stop working because the voltage does not meet the device's requirements. When this chip is used in this design, the discharge voltage will be perfectly fixed at 1.5V. This voltage is equivalent to the full charge voltage of a regular dry cell battery. That is, changes in charge will not cause changes in voltage, and there will be no situation where the voltage is lower than the voltage required by the device. Therefore, the efficiency is greatly increased.

[0042] like Figure 6 As shown, the power display section consists of an HM1160 power display IC, a button KEY1 (surface mount miniature button), a resistor R7 (330Ω), and LEDs LED3 (red), LED4 (yellow), LED5 (yellow), and LED6 (green). The VDD (pin 1) of the HM1160 power display IC is connected in series with button KEY1 and then to the positive terminal of the rechargeable lithium battery. The GND (pin 2) of the HM1160 power display IC is connected to the negative terminal of the rechargeable lithium battery. Pin D4 (pin 3) of the HM1160 power display IC is connected in series with LED6, then with resistor R7, and finally to VDD (pin 1) of the HM1160 power display IC. Pin D3 (pin 4) of the HM1160 power display IC is connected in series with LED... LED5 is connected in series with resistor R7 and then connected to VDD (pin 1) of the HM1160 power display IC. D2 (pin 5) of the HM1160 power display IC is connected in series with LED4 and then with resistor R7 and then connected to VDD (pin 1) of the HM1160 power display IC. D1 (pin 6) of the HM1160 power display IC is connected in series with LED3 and then with resistor R7 and then connected to VDD (pin 1) of the HM1160 power display IC.

[0043] The power display section is designed with reference to the HM1160 power display IC datasheet. Since the HM1160 power display IC is a professional single-cell lithium battery power display IC, it can effectively display the current power of the rechargeable lithium battery, allowing users to intuitively see the remaining power of the rechargeable lithium battery during use and helping to improve the user experience.

[0044] The rechargeable lithium battery used in this design is a conventional lithium-ion battery, characterized by the use of lithium cobalt oxide as the positive electrode material and a battery voltage of 3.7V.

[0045] The above four circuit components, along with the rechargeable lithium battery, constitute this utility model patent. This novel rechargeable battery perfectly achieves the following: ① It replaces and surpasses existing nickel-cadmium or nickel-metal hydride rechargeable batteries, with a discharge curve even more perfect than that of ordinary dry cell batteries; ② It is safer than using conventional batteries; ③ It can display the remaining power, making it more convenient to use than conventional batteries; ④ It avoids the overcharging problem of conventional nickel-cadmium or nickel-metal hydride rechargeable batteries.

[0046] The use of rechargeable lithium batteries can be divided into two parts: charging and use, which will be described separately below:

[0047] Charging: Connect a regular charger to the charging interface using a charging cable. This design will automatically perform the charging function. When charging, the red LED1 will light up; when fully charged, the green LED2 will light up; when there is undervoltage, excessively high or low temperature during charging, both the red LED1 and the green LED2 will light up.

[0048] Usage: When using this device, simply install it on the electrical appliance like a regular dry cell battery. To check the remaining battery power, press button KEY1. The four LEDs (LED3-LED6) on the battery will display the current battery level: all four LEDs lit indicates 100% remaining power, three LEDs lit indicates 75% remaining power, two LEDs lit indicates 50% remaining power, one LED lit indicates 25% remaining power, and none of the LEDs lit indicates 0% remaining power.

Claims

1. A rechargeable lithium battery, characterized in that, include Lithium batteries; The lithium battery protection circuit is used to input electrical energy into the lithium battery or output electrical energy from the lithium battery. A lithium battery charging circuit, wherein the lithium battery charging circuit is used to input electrical energy into a lithium battery protection circuit; A voltage regulator output circuit, which is used to output the electrical energy of the lithium battery protection circuit; A power display circuit is used to display the power level in the lithium battery.

2. The rechargeable lithium battery of claim 1, wherein, The lithium battery protection circuit includes a DW01 chip and a WST8205A dual NMOS transistor.

3. The rechargeable lithium battery of claim 1, wherein, The lithium battery charging circuit includes a TP4056 charging chip, which is connected to a TAPYC charging interface.

4. The rechargeable lithium battery of claim 1, wherein, The voltage regulation output circuit includes an AMS1117 voltage regulation output chip.

5. The rechargeable lithium battery of claim 1, wherein, The power display circuit includes an HM1160 power display chip.

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