Battery for solar cell: overview, types, characteristics

The use of solar energy is an alternativeirreplaceable sources of energy. Modern technologies allow the use of solar panels for street lighting, heating and lighting of small houses. Today, it is not uncommon for solar panels for summer cottages, which allow the household to provide electricity in the summer.

Solar panels

A device that is a large number of photoelectric converters connected in a single system, and there is a solar battery.

For a solar battery, it is important to have direct sunlight, the energy of which is converted into an electric current.

Batteries are installed in areas wheresunny days make up most of the year. However, the geographical breadth affects the efficiency of solar batteries. Because the farther from the pole, the more powerful the sun's rays. But even in the middle zone of Russia in winter, solar panels reduce electricity consumption from common networks, and in summer it becomes possible even to sell its surplus.

Solar batteries are single-crystal, polycrystalline and thin-film.

Directed in different directions crystals inpolycrystalline batteries allow you to reduce the dependence on direct sunlight. Such batteries are today the most common, they are used for lighting public buildings and private houses. Often, street lighting on a solar battery is of a polycrystalline type.

Solar cells for cottages

More recently, the main argument againstinstallation of solar panels in the country was their cost. Today, this production begins to produce domestic industry, its prices are lower, the choice is wider, and service maintenance is more affordable.

Modern technologies are quite capable of copingwith lighting the area and ensure the operation of household appliances. True, this requires a battery for the solar battery, and also a charge controller and an inverter that converts DC to AC.

Today you can buy a complete setsolar mini power station for a summer residence or a small house with autonomy of work within 24 hours. The power of such a power plant is 235 W with a battery power of 2.4 kWh.

Accumulators for solar batteries

Rechargeable batteries are an important part of the modern solar system equipment.

In bright sunny days, solar panelsproduce much more electrical energy than electrical appliances, and at night, when lighting is particularly important, do not work at all. Hence, it is necessary to store and store electricity for its subsequent use.

A rechargeable battery for a solar battery and is designed for uniform and uninterrupted power supply.

Also, the batteries (battery) overlappeak loads, too large for photomodules, use stored energy in the dark, compensate for the difference in the generated and consumed energy in cloudy weather.

Ways of connecting the battery

More often than one battery is not enough forfull-fledged operation of the solar power plant, and it is necessary to use several similar batteries. Experts believe that they should be from the same party.

Three ways to connect (switch) the battery are used to increase the overall capacity of the system.

With a parallel connection, all the batteries are stacked, and the total voltage is equal to the voltage in one device.

The serial connection, on the contrary, allows to sum all the voltages, and the capacity remains equal to the capacity of one battery in the circuit.

The most productive is a combined serial-parallel connection, in which both voltages and capacitances are summed.

True, with such a combination of battery exposedunbalance, that is, the total voltage will be constant calculated, but for each individual battery its readings will change. This phenomenon leads to the fact that some of the batteries are not recharged, and some are charged above the norm, and the resource is produced prematurely.

Therefore, each solar system must include a solar battery charge controller and jumpers, which connect the middle points for self-leveling of the voltage in the battery.

Features of storage batteries for solar systems

Rechargeable battery for solar batterymust satisfy a number of requirements. It must withstand a large number of charge / discharge cycles. At the same time self-discharge should be minimal, and the value of the charging current is large, the operating temperature range is wide.

Today, manufacturers are already producing special batteries, so-called solar batteries, which fully meet these requirements.

A set of solar cells with such devicesand the charge controller allows you to accumulate energy and store it with maximum efficiency. A network inverter - convert it to connect household appliances and lighting.

Criterias of choice

You need to choose a battery for solar panels for the house by several parameters.

The most important is the capacity. Based on the required power consumption, the estimated capacitance value is calculated, increases by 35-50%, and already one or several devices for parallel connection are selected for it. The battery with sufficient capacity holds up to 4 days.

Duration of discharge and charging. Of the two devices with the same capacitance rating, the one for which a shorter time interval for charging is required is preferable.

The capacity of a lead-acid battery depends on the mass of lead in it, so the more the battery mass, the higher its real capacity. When choosing, pay attention to the weight and dimensions of the device.

Manufacturers set a range of operating temperatures and frequency of maintenance for their products, and these indicators should also be taken into account.

The accompanying documents always stateterm of use of the battery, the number of random cycles (the more this factor, other things being equal, the better) and the amount of self-discharge per month.

When calculating the parameters of the battery, you need to take into account the energy losses during storage and conversion. The efficiency of modern devices for solar systems is about 85%.

Types of batteries for solar panels

Accustomed car batteries are not designed for a large number of cycles and differ in significant self-discharge. For heliostations, completely different devices are used.

1. AGM-accumulators, in the construction of which between the absorbing glass mats is in the bound state of the electrolyte. Such a device can be operated in any position, at a low price and a charge depth of about 80% can withstand up to 500 cycles and are characterized by a high level of charge.

Term of operation is not so great - 5 years, andthe operating temperature range is limited to 15-25 ° C, but they are quickly charged - it takes less than 8 hours for a full recovery, can be transported in a charged state and operated in a room with insufficient ventilation.

AGM-batteries quickly fail because of overcharging, but undercharging is transferred quite satisfactorily.

2. A gel battery for a solar battery can also work in any position. The gel-like gel electrolyte is retained in the pores of silica gel, which serves as a spacer for the plates. The indisputable advantage of this design - the electrodes do not crumble, because the entire free space is filled with gel, and therefore, the possibility of a short circuit is excluded. In addition, they can withstand full discharge and a significant number of cycles, about one and a half times more than similar AGM-batteries. But their price is much higher.

Despite the price, gel batteriesmore economical, do not need maintenance, can be in a fully discharged state without damage being a few days, energy losses in them are insignificant because of small self-discharge.

3. OPzS batteries, so-called fillers with liquid electrolyte that do not require maintenance, are designed specifically for discharge with small currents. They withstand a very large number of deep cycles, they are used, as a rule, in powerful expensive solar systems, and they themselves are quite expensive.

Solar charge controller

Electronic devices are designed to control and adjust the level of charge on the battery. They protect the battery from complete discharge, and from excessive charging.

Charge controllers are very important elementssolar panels. They provide a multi-stage battery charge, automatic shutdown when the battery is fully charged and with a minimum charge - loads, connecting the photomodules when the battery needs to be charged, and reconnecting the loads after charging.

The cheapest and most primitive kind of controllers of the typeOn / Off disconnects the solar panels from the battery when the voltage reaches the limit value, not allowing the batteries to fully charge and thereby reducing their life.

PWM controllers working on PWM(pulse width modulation) - technology, economical and effective in areas with high sun activity. They stop charging, allowing the battery to fully charge. Installed such devices in low-power, up to 2 kW, systems with a small capacity battery.

The MPRT controllers control the maximum energy peaks. They are most effective in solar systems, but also much more expensive than other models.

Manufacturers of batteries for solar panels

In the Russian market there are not many manufacturers of this type of products.

CSB Battery Co., Ltd (Taiwan) offers lead-acid batteries manufactured using AGM technology, with a lifespan of up to 10 years, rated at 12 V, from 26 to 100 Ah at a price of 2.6 to 8.2 thousand rubles .

Approximately the same batteries are produced by Shandong Sacred Sun Power Sources Co., Ltd (China).

HAZE Battery Company Ltd (UK)supplies gel batteries with a service life of up to 12 years, working voltage 12 V, capacity from 15 to 230 A * h and a temperature range from -20 to +50 ° C at prices ranging from 7 to 28 thousand rubles.

SSKGroup (Russia-Belgium) produces reliable gel storage batteries for solar batteries with a flame arrestor with a service life of 15 years, capacity from 100 to 180 A * h at prices from 11 to 19 thousand rubles.

Manufacturers of solar panels

The main manufacturers of solar panelsFor a long time there were Japan, Germany, USA and China. Russian solar panels are assembled from materials produced in these countries. The most popular domestic solar batteries with an affordable price are made of polycrystalline silicon, produced in Germany and the United States.

Today Russian manufacturers not only produce solar modules, but also develop new ones, such as Kvant in Moscow.

Krasnodar company "Sunny Wind" produces not only modules, but also ready-made home solar stations. He designs ready-made solar systems and "SolarInTech" from Zelenograd.

In the domestic market, more and more equipmentfor solar systems, including ready-made standard designs. But with some engineering skills and perseverance, you can independently calculate the system for specific operating conditions and pick up the necessary equipment: solar panels, batteries, controllers of different manufacturers in a wide price range. Thus it is possible to save on some components, having collected them independently from improvised materials, for example, the controller.