CN108092365B - Battery Charger with Power Evaluation - Google Patents

Abstract

The invention discloses a battery charger with power evaluation, comprising a battery compartment, a voltage sensor, a current sensor, a charging module, a control module and a load for evaluating the battery power; a charging output end of the charging module is connected to a switch The device K1 is connected in series with the current sensor and then connected to the electrode of the battery, the voltage sensor is connected to the electrode of the battery, the output terminals of the current sensor and the voltage sensor are connected to the input port of the control module, and the load is connected in series with the switch device K2 and then connected to the two terminals of the voltage sensor. The control terminals of the switching device K1 and the switching device K2 are respectively connected to the output ports of the control module. Through the power evaluation function, users can grasp the current actual power of each battery in time, so as to judge whether the battery is in a state that needs to be replaced. Such a function helps to reduce unnecessary battery waste, contributes to energy saving and emission reduction, and is beneficial to environmental protection.

Description

Battery Charger with Power Evaluation

technical field

The present invention relates to a battery charger, in particular to a battery charger with an electric quantity evaluation function.

Background technique

Many electronic toys, digital products, etc. use rechargeable secondary batteries, and naturally they are inseparable from battery chargers. According to the type of charging, it can be roughly divided into built-in and external charging. Among them, the built-in type means that the battery is left inside the electronic product, and the output of the transformer is connected to the electronic product, and the battery is not disassembled during the charging process; and the external type means that the battery is disassembled from the electronic product and placed in the charger. while charging.

One of the more common external chargers at present is for AA-size (AAA) or AA-size (AA) rechargeable batteries, which can charge 4 secondary batteries at the same time. This kind of external charger usually only has several LED indicators. When a battery is placed in a charging compartment and is in a charging state, the indicator light is on; and when no battery is placed or the battery is fully charged, the indicator light is off.

There are general inconsistencies in batteries. For example, there are 4 rechargeable batteries with a nominal capacity of 1000mAh. After half a year of use, it is found that the actual current capacity of the batteries is 900mAh, 950mAh, 850mAh, and 500mAh. Because the batteries are often used in series Yes, it has a short board effect. If the above 4 batteries are used in series, it is limited by the battery with the smallest power. The actual overall power is only 500mAh, which is only half of the nominal power. Since the specific performance of each battery is not known, the measures taken by the user at this time are often to eliminate the four batteries together, which will cause huge waste.

SUMMARY OF THE INVENTION

In view of the above-mentioned shortcomings of the prior art, the present invention provides a battery charger with power evaluation, so that the user can grasp the current actual power of each battery while fully charging the battery during use, so as to determine whether the battery has arrived. Status that needs to be replaced.

The present invention achieves the above object in this way:

A battery charger with power evaluation, including a battery compartment, a voltage sensor, a current sensor, a charging module, a control module, and a load for evaluating the battery power; the charging output end of the charging module is connected to the switching device K1, and then the current is connected in series The sensor is connected to the electrode of the battery, the voltage sensor is connected to the electrode of the battery, the output terminals of the current sensor and the voltage sensor are connected to the input port of the control module, the load is connected in series with the switch device K2 and then connected to both ends of the voltage sensor, the switch devices K1 and The control terminals of the switching device K2 are respectively connected to the output ports of the control module.

Wherein, there is also a display module for displaying battery charging state and battery power information, and the display module is connected with the output port of the control module.

Among them, a mode selection button is also provided, and the mode selection button is connected with the input port of the control module.

The beneficial effects of the present invention are as follows: the control module controls the charging module to charge the batteries in parallel with constant current and constant voltage until the current on each charging circuit is less than the threshold value, and the control module controls the load to work with the power evaluation function. During power evaluation, the battery is connected in parallel to discharge the load at a constant current, and the control module collects the current and voltage data during the discharge process to calculate the current power of the battery. Through the power evaluation function, users can grasp the current actual power of each battery in time, so as to judge whether the battery is in a state that needs to be replaced. Such a function helps to reduce unnecessary battery waste, contributes to energy saving and emission reduction, and is beneficial to environmental protection.

Description of drawings

Below in conjunction with accompanying drawing, the present invention is further described:

Fig. 1 is the principle block diagram of the present invention;

Fig. 2 is the working flow chart of the ordinary charging mode of the present invention;

FIG. 3 is a working flow chart of the present invention in the charging mode of the charging capacity evaluation function.

Detailed ways

As shown in Figure 1, the battery charger with power evaluation includes a battery compartment, a voltage sensor, a current sensor, a charging module, a load, a control module, a user mode selection button and a display module; it is configured between the positive and negative poles of the battery compartment A voltage sensor monitors the voltage across the battery, and the result of the voltage monitoring is sent to the control module. A current sensor is configured on the charging circuit of each battery to monitor the charging and discharging current of each circuit, and the monitoring results are transmitted to the control module. The charging module customizes the DC power supply according to the charging characteristics of the battery, and is responsible for converting the 220V AC power supply into DC output. The output voltage of the power supply is determined according to the type of the battery to be charged. At present, the general type of rechargeable secondary battery is a nickel-metal hydride battery or a nickel-cadmium battery, the rated voltage is 1.2V, and the charging voltage can be set to about 1.35V to ensure that the battery can be fully charged and not overcharged.

The user mode selection buttons include "normal charging mode" and "charging mode with power evaluation function", and the user selects which mode currently needs to be used to charge the battery through the "mode selection button". The load is a resistive component used to complete the discharge process of the battery in the "charge mode with capacity evaluation function". The control module is realized by a single chip microcomputer and its peripheral auxiliary circuits. As the brain of the whole charger, the control module is responsible for receiving and processing various input information, controlling the charging and power evaluation process, and transmitting the battery information to the display module to inform the user.

Wherein, the working mode of the common charging mode is that the control module controls the charging module to charge the batteries in parallel with constant current and constant voltage until the current on each charging circuit is less than the threshold value. The working mode of the charging mode with the power evaluation function is that the control module controls the load operation and discharges the battery in parallel with constant current. When the parallel voltage is lower than this threshold, the discharge will be stopped. The threshold value can be set according to the type of the battery. If the type of the rechargeable secondary battery is a nickel-metal hydride battery or a nickel-cadmium battery, the discharge cut-off voltage can be set to 0.8V. Then, the control module controls the charging module to perform constant current and constant voltage charging on the batteries in parallel until the current on each charging circuit is less than the threshold value. After the charging is completed, the control module transmits the charging power obtained by accumulating the current to the display module to inform the user.

The main working process of the battery charger with power evaluation is as follows:

(1) In the normal charging mode, referring to Figure 2, the switching device K1 is closed, and the battery is charged in parallel with constant current and constant voltage. As the charge in the battery gradually approaches saturation, the corresponding current on the charging circuit will increase. smaller. Set a detected current threshold value I charge. If the current on each charging circuit is less than I charge, it means that all batteries are fully charged. At this time, the charging control switch device K1 can be disconnected, and the charging is over.

(2) In the charging mode with the power evaluation function, the control module will start the corresponding working mode. This mode can be regarded as a combination of a discharge process and a charge process.

In the initialization phase of the program, referring to Figure 3, the battery power Q1, Q2, Q3, and Q4 are all cleared to prevent the previous evaluation result from affecting this time. Then the switching device K2 is closed, and the battery enters the discharge state. This state will not be until all the batteries are discharged. As the charge in the battery gradually approaches the discharge, the corresponding current on the charging circuit will become smaller and smaller. Due to the discharge The current cannot be 0. The basis for judging that the battery has been discharged is to set a threshold value of U discharge for voltage detection. If the parallel voltage is less than the U discharge, it means that all batteries have been discharged.

After that, the switching device K2 is turned off, the switching device K1 is turned on, and the battery enters the charging stage. In the charging stage, the charging current flowing through each battery will be converted into electric power, and will be accumulated into the battery power Q1, Q2, Q3, and Q4 accordingly. As with the "normal charging mode", the condition for judging the end of the charging process is that the current on each charging circuit is less than I charge, that is, the battery is fully charged. At this time, the switching devices K1 and K2 are both disconnected, and the control module displays the accumulated battery power Q1, Q2, Q3, and Q4 to the user through the display module, and the user knows the battery power.

Claims (3)

1. A battery charger with power evaluation, characterized in that it includes a battery compartment, a voltage sensor A, a current sensor V, a charging module, a control module and a load for evaluating the battery power; the charging output end of the charging module Connect the switching device K1, then connect the current sensor in series and then connect to the electrode of the battery, the voltage sensor is connected to the electrode of the battery, the output terminals of the current sensor and the voltage sensor are connected to the input port of the control module, the load is connected in series with the switching device K2, and then the voltage sensor is connected The two ends of the switching device K1 and the switching device K2 are respectively connected to the output ports of the control module; in the charging mode with the power evaluation function, the control module will start the corresponding working mode; this mode consists of a discharging process and a charging The process is combined; in the initialization stage of the program, the battery power Q1, Q2, Q3, and Q4 are all cleared to prevent the previous evaluation result from affecting this time; then the switching device K2 is closed, and the battery enters the discharge state. The state should be until all batteries are empty. As the charge in the battery gradually approaches emptying, the corresponding current on the charging circuit will become smaller and smaller. Since the discharge current cannot be 0, the basis for judging that the battery has been empty is , set a voltage detection threshold U discharge, if the parallel voltage is less than U discharge, it means that all batteries have been discharged; then the switching device K2 is turned off, the switching device K1 is closed, and the battery enters the charging stage; in the charging stage , the charging current flowing through each battery will be converted into electric power, and will be accumulated into the battery power Q1, Q2, Q3, and Q4 accordingly; the condition for judging the end of the charging process is that the current on each charging circuit is less than I charge, That is, the battery is fully charged; at this time, the switching devices K1 and K2 are disconnected, and the control module will display the accumulated battery power Q1, Q2, Q3, and Q4 to the user through the display module, and the user will know the battery power. 2 . The battery charger with electric quantity evaluation according to claim 1 , further comprising a display module for displaying battery charging status and battery quantity information, and the display module is connected to the output port of the control module. 3 . 3 . The battery charger with electric quantity evaluation according to claim 1 , wherein a mode selection button is further provided, and the mode selection button is connected to the input port of the control module. 4 .

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