JPH0833231A - Portable power supply with battery charger - Google Patents

Abstract

PURPOSE:To increase the number of charging/discharging times of a secondary battery on the next stage by operating the primary of a battery charger with a voltage as low as possible and increasing the secondary voltage slightly higher than the voltage of a secondary battery before feeding power to the secondary battery on the next stage. CONSTITUTION:The secondary voltage for quick charging is temporarily lowered by means of a reverse flow prevention diode 2, a quick charging secondary battery 3 connected in parallel with the cell 1 in order to store the charges received therefrom, and a DC-DC converter 4. The DC output then passes through a chopper to produce pulsating power which is boosted and smoothed to obtain a voltage higher than that of a secondary battery on the next stage thus feeding power, as required, to the secondary battery through a voltage converter 5. The operating time of an electric double layer battery as long as that of a general battery is ensured by lowering the output voltage of the electric double layer battery as low as 1V, for example. The voltage is fed through a chopper and boosted again in order to charge a secondary battery on the following stage thus realizing a perpetual operation through the secondary battery.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery power source, and more particularly to a solar cell called a solar cell, which is mainly used for manufacturing a secondary battery which converts sunlight into electricity and stores the converted electricity. There is a battery that stores energy as electricity.
A solar battery is a power supply that converts sunlight into electricity, stores it in a storage battery, supplies the stored electricity in small amounts to a few types of transistor devices at the same time, and allows them to operate in parallel. is there.

Japanese call a cell for converting sunlight into electricity a "solar cell", which is a mistake. The cell has only the function of a converter that converts sunlight into electricity, and has no function of storing electricity. A storage battery is needed to store the generated electricity. Solar cells are also a technology that started by reducing the ambiguity of this word.

The sun is centered on the equator on the earth, and is 6 north and south latitudes.
An average of 1 m ² (1 m × 1 m) of 1 KW of energy is poured in the range of 5 °. To convert this energy into electricity, semiconductor single crystals having an efficiency (conversion efficiency) of 15 to 16%, polycrystals having an internal or external rate of 14%, and amorphous (non-crystalline) having an efficiency (conversion efficiency) of 7 to 8% are used. When these are used to illuminate a domestic light bulb (100 W), a single-cell or poly-crystal cell produces an amount of electricity that only one light bulb shines in a 1 m ² cell while the sun is being poured. Then it is impossible to light this light bulb. Comparing these from the viewpoint of cost, which is the basis of the technology, most single crystals are produced by first refining a polycrystal and then refining it through a process such as a pulling method. Higher than polycrystalline. Even if the conversion efficiency is increased by 1 to 2% as described above, the cost is usually more than double that of the polycrystalline cell.

On the other hand, the conversion efficiency of amorphous is only half that of polycrystalline. In the manufacturing process, there is almost no cost difference between amorphous and polycrystalline. Moreover,
Amorphous cells suffer from the disadvantage of deterioration over time, which is a characteristic that deteriorates over time. Then, in order to obtain the same performance, an area twice as large as the area of the polycrystalline cell is required. While the polycrystal having a conversion efficiency of 14% per 1 m ² described above produces electric energy of 130 to 140 W, the amorphous requires a cell plane of 2 m ^{2 which} is twice as large. That is, the costs do not match each other.

Currently, the electric power for electric lights and heavy industry is 100 to 20.
It is supplied by 0V AC commercial power supply. The source is
Hydropower, coal fired power, oil fired power, LPG fired power, or nuclear power. These energy sources are very large,
It is not a small energy that can be covered by each household. At the same time, it is too dangerous to use in each home. For this reason, it is installed on a large scale in a place away from private houses such as mountains, valleys and the sea, and the voltage is increased to 100V, 200V to deliver this energy to a long distance.
The current situation is that they are sent via power lines and distributed to homes and factories. If you do not do this, you will not be able to manage and the cost will not be cheap. We call this the centralized management method, and this management method is left up to the electric power company and the country.

On the other hand, the solar cell has one
For example, a cell of m ² has a conversion efficiency of 100%, but 100 W
Only 10 bulbs generate enough energy while the sun shines. This is covered by power transmission and distribution in homes and factories, called power sale if necessary, with a cell on the roof or fence of the home, and having the power company buy some of the power generated during the day. Partly adopted. However, while this method is extremely significant,
From a technical point of view, the cost is too high, and this can only consume less than 20% of the energy. Furthermore, countries like Japan that are well equipped for power transmission and distribution are rare in the world, and in neighboring China, many countries in Southeast Asia and the Middle East, such power transmission is completely impossible. Even in the place where there is no wiring on the sea or in the mountains, its life is difficult as well. Currently, the majority of semiconductor circuits used in home appliances are those with 3.3V memory element drive and 5.5V driver circuit element, and it is 100V to operate these circuits. Commercial power source is used. The AC voltage of 100 V is dropped and the amperage is converted to a DC power source for digital signals for use. 1
When using a commercial power supply of 00V to drop the voltage and current for IC circuits of 12V or less, a) There are legal restrictions under the Electricity Business Act, and there are various restrictions on handling, and it is permissible to tamper with it at home. Not done. B) If the transistor circuit has a PNP-NPN complementary configuration, unless the two have similar characteristics, an unbalanced current will be generated in the electrodes on the switching transistor side, causing a short circuit or a large current flow, resulting in a fire. It may happen that an unintended phenomenon, such as PNP
Alternatively, since a large current flows in a power supply of a grounded transistor circuit element of NPN alone, the power supply is consumed so much that sometimes the current amount becomes too large, and the circuit is short-circuited or an overcurrent is applied to the load. May be shorted.

Therefore, the most suitable power source for a transistor circuit depending on a voltage of 20 V or less and a current of 2 A or less is to generate electricity in a solar cell and use a solar battery that stores the electricity as a power source.

More specifically, a device using a semiconductor (most of which is driven by an electrode of 6 V or less), or a 12 V voltage like a car is used together with a cell. By loading a secondary battery (this secondary battery may also be used as an on-board lead battery), and a mechanism that drives it with a hybrid configuration with energy from gasoline-this is a single unit without wiring. It is called a distributed processing mechanism because it can be processed by the-, but in the case of-, the energy to move the equipment needs only a few hundredths / thousandth of the energy of the conventional centralized control system power supply, and most of it can be covered by the distributed processing mechanism power supply. Can be done. In other words, in addition to the centralized control system, the power source that is a distributed processing system and uses solar battery technology is kind to the equipment and also serves as a power source that prevents environmental damage that would not require battery replacement for years and decades. In that sense, the solar cell is a technology that can cover 90% or more of semiconductor circuit equipment for a long time with about 1% of the total energy.

[0009]

2. Description of the Related Art As a conventional technique, there is a system in which electricity from a silicon cell is stored in a lead acid battery or a nickel-cadmium battery for automobiles and the transistor device is operated by using this.
However, with this method, the secondary battery must be charged and discharged 400 times or less. Among the rechargeable batteries, the lead storage battery electrode has lead sulfate (PbSO
₄ ) An insulating layer is formed, which prevents charging from going as expected. Lead sulfate cannot be decomposed without strong charging. For this reason, the charge and discharge will be 200 times or less. Weight becomes heavy. 8kg for 12V in case of lead acid battery
It will be about 10kg. Since the nickel-cadmium battery and the lithium battery have a limited number of charge / discharge cycles, the cost is high.

[0010]

SUMMARY OF THE INVENTION The present invention is intended to improve the above-mentioned deficiencies and significantly improves the life of a secondary battery.
The secondary battery thus far can be continuously used for more than 5 years almost permanently.

[0011]

A portable power source with a battery charger according to the present invention is a secondary battery which is charged at high speed,
For example, an electric double layer battery using activated carbon as an electrode is installed in the rear stage of a cell that receives sunlight and generates power, operates at a voltage extremely lower than the secondary voltage, and temporarily boosts this voltage to supply power to the next stage. A secondary converter that supplies a primary converter is provided, and a secondary voltage that is charged by the output of the primary converter after supplying a constant voltage and a DC-DC converter for supply to the subsequent stage, if necessary, and that supplies power to a load at the subsequent stage. battery,
For example, it is characterized in that a secondary battery such as NiCd or lithium is installed.

[0012]

[Function] According to the Japan Meteorological Agency's announcement, the average daily sunshine time in one year of Japan is 3.8 hours. On the other hand, 1
The charging time for a general battery for 2V, for example, a lead secondary battery, a nickel cadmium secondary battery, or a lithium secondary battery from 1V or less is 4 to 6 hours at the earliest. This means that charging is not completed in an average day. The present invention, by taking the above-mentioned means, completes the accumulation of the power generated in the cell in the secondary battery of the first stage within at least one hour (tens of minutes), and the storage amount of this secondary battery (F = 1 × In order to effectively utilize T / V), the primary side is operated with a voltage as small as possible, for example, 1 V, the secondary side is raised to a voltage slightly higher than the voltage of the secondary battery of the next stage, and then this power is next By extending the number of charge / discharge cycles of the next-stage secondary battery-usually this is called breathing of the secondary battery-by supplying the secondary-stage secondary battery (the normal secondary battery breathing is limited to 400 times. However, by increasing the breathing time of the battery)
It allows more than one breathing, and makes it possible to use the next-stage secondary battery for almost 5 years or more continuously. As the secondary battery for high-speed charging at the first stage, an electric double layer battery is usually used so that the number of times of charging and discharging can be made almost infinite.

[0013]

The present embodiment will be described with reference to the accompanying drawings. In FIG. 1, reference numeral 1 is a cell for converting sunlight into electricity, and specifically, a cell having a size and an output as shown in the figure was used. 2 is a backflow prevention diode, 3 is a cell 1
Secondary battery for high-speed charging that is connected in parallel with and stores the electricity sent from the cell (the electric double-layer battery was used, but it is not limited to the electric double-layer battery if high-speed charging is possible), 4 After the secondary battery for high-speed charging is once made into a low voltage by the DC-DC converter, the direct current output is further converted into a pulse by the chopper, the output is boosted and smoothed, and the voltage is made higher than the secondary battery at the next stage. Power is supplied to the rear secondary battery (NiCd battery, lithium battery, or the like) via the voltage conversion device 5 as necessary. Reference numeral 6 is a backflow prevention diode, and 8 is a load. Specific values are shown below each. Also, note that the capacity of the electric double layer battery used here is about 1/10 of that of a general battery.

If so, whether the electric double layer battery is useful or not is not so. The voltage characteristic of the electric double layer is a characteristic of a capacitor known to humans, that is, a low-current type characteristic with a downward slope as shown in FIG. Therefore, the output of the cell 2 is set to about 12 V so that the electric double layer battery 3 can be stored in a short time. By the way, if the electric capacity of the electric double layer battery 3 is 75F,

[0015]

[Equation 1]

Within 30 minutes (27.5 minutes in calculation), saturation is reached, and then a current of 230 mAh is supplied to the output side. By the way, a pure battery, such as a 12V lead battery for an automobile, can be charged at 5A.

[0017]

[Equation 2]

It takes about 3 hours and 2 to 8 hours to charge 2A, which means that it takes 2 days to charge the battery. As described above, it is difficult for the electric double layer battery 3 to serve as a battery by itself at the present capacity. Of course 0.001
It can be used as a battery for internal and external A (1mA) watches and some liquid crystal products, but it is difficult for transistor devices of about 1A. For some reason it is like the calculation above

[0019]

(Equation 3)

This is because the battery will cease to function in about 14 minutes. Of course, if Mr. Omichi is out, it will be charged more than 1A, so this can be covered, but the point is the problem after sunset.

Therefore, the pure secondary battery must be taken care of. Secondary batteries such as NiCd secondary batteries are needed as main batteries. However, this secondary battery is best charged and discharged about 400 times. 1000
It seems that it can be used only once, but it does not currently exist and it does not match the cost at all. Speaking of about 400 times of charge and discharge, it will be useless within a year or at most two years. Therefore, it is necessary to make the effective time of the secondary battery substantially long as shown in FIG. 3 by constantly performing the charging about 400 times while the charging power is low. For that purpose, the secondary battery 3 for high-speed charging at the first stage is made to be an electric double layer battery, and as shown in Formula 1, it is filled up within 30 minutes. At this time, what is important is the voltage of the secondary battery for high-speed charging after the tank is full, and the battery should be configured if it can be cut. This is because the heat generation in the secondary battery is made as small as possible by the extra current. The output of cell 1 in FIG. 1 is 16V,
Assuming that a 300 mA, 5.3 W class is used, and an electric double layer 75 F, 230 mA output is used, the tank will be full within 25 minutes as shown in the formula 1 and then 2
It can supply current with an output of 30 mAh. By the way, the electric double layer battery has a low-current characteristic of a downward sloping rightward as described above and as shown in FIG. Therefore, by lowering the output voltage of the electric double layer battery to a low voltage of, for example, 1 V, the operating time of the electric double layer battery is secured as long as a general battery, and then it is converted into an alternating current by a chopper or the like to boost the voltage again, for example, 8 V. , 100 mA, and after that, if a secondary secondary battery, for example, a normal NiCd battery (rated 6 V, 900 mAh) wireless telephone battery is charged, a wireless telephone operated by this secondary battery (for example, 6V, 50mA, 0.3
W) can be operated for many years. The grounds for this are NiCd batteries, which are currently on the market and have a rating of 6.0V and 900mA, continuous talk time of 120 minutes and 450mA, and continuous standby time of 21 hours and 43mA. If you are on a call, the electric double layer battery can supply current at 230mA ≈ 450mA / 2 for about 30 minutes, and the next-stage secondary battery is still 900m.
If A-230 mA = 670 mA and this is the continuous standby time, then 670 ÷ 43≈16 hours. Since the average sunshine time is 3.8 hours / day as described above, this time can be completely covered by the electric double layer battery, and is approximately 24 hours.
It can be used without turning off the power for an hour.

Here, it is necessary to briefly describe the DC-DC converter 4. The electric double layer battery has a voltage characteristic that drops to the right. Therefore, in order to use this effectively, the input of the converter 4 should be kept low and now it is set to 1 V inside or outside (the constant current is 230 mA and a constant current can be obtained). This can be once converted into an alternating current by a chopper or the like, and then boosted and smoothed to provide an output of about 8 V · 100 mA, which allows the secondary battery of the next stage to be sufficiently charged.
Also, the wireless telephone is usually 6V, 50mA, 0.3W
Since it is only a degree, there is no problem in this operation.

The solar battery power source for wireless telephones has been described above.

Then, how can a solar battery supply power for a laptop computer that consumes 60V, 3A and 18W?

First, make the cell a little larger (0.8 V, 3
A, 2.4 W, 10 cm x 10 cm x 0.5 per sheet
It is necessary to prepare 16V, 6A, 100W cells (two wafers having a size of 50 cm × 40 cm × 0.5 mm) having a wafer of mm).

[0026]

[Equation 4]

A solar battery having a capacity of is required.

If the current when the PC is not operating is reduced to 1/3 or less of the current when the PC is operating, this solar battery should be sufficient.

[0029]

In summary, according to the portable power source with the battery charger of the present invention, 90% of the semiconductor electric equipment can be obtained.
By the distributed processing, the above can be used in each home, and a power source that can be used as a part of the power source of the carrier vehicle such as the supply of instantaneous pulse voltage and current including the ignition of the vehicle can be obtained.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a portable power supply with a battery charger of the present invention.

2 is a voltage characteristic of the electric double layer battery 3. FIG.

[Explanation of symbols]

 1 cell 2.6 reverse-current prevention diode 3 secondary battery for high-speed charging 4 DC-DC converter 5 voltage converter 7 secondary battery 8 load

Claims (1)

[Claims] 1. A secondary battery which is charged at high speed is arranged in a subsequent stage of a cell which receives sunlight and generates electric power, operates in parallel with the secondary battery at a voltage extremely lower than the voltage of the secondary battery, and temporarily operates this voltage. A portable power supply with a battery charger, which is equipped with a converter that boosts the voltage to supply power to the next stage, and is equipped with a secondary battery that is charged by the output of this converter and that supplies power to the load in the subsequent stage.