There is no doubt that we rely on electric appliances to perform many of our daily routine activities. This is why the demand for electricity is increasing day by day.

Fossil fuels are the major source of electricity generation, but that is not a clean energy source. They pollute the air with green house gas (GHG) emissions. Renewable power generation sources are not net GHG polluters.

Increasing proportions of the electricity generated comes from renewable sources with more residential rooftop solar panels being installed each year. Solar power installations are often subsidised but then so too coal powered generators obtain a subsidy.

We are unlikely to stop subsidizing the use of fossil fuels for power but we might want to leverage the benefits of clean power generation to benefit our future generation's air quality.

Fortunately, with advancing technology, we can use the renewable energy resources in wind, water and sun. The sun is an unlimited power source that is available free to us every day.

Rooftop solar panel systems backed by the best battery storage for solar is the cheapest alternative to fossil fuels for residential power users.

If you install a solar power system, invest in getting the best battery storage for solar power.

Batteries compliment a photovoltaic system by storing the DC energy produced by the solar panels. Energy generated and stored during the daytime is available when the sun sets. This store of energy runs electronic appliances in your house.

In 2018 more home battery storage capacity was installed than the existing supply. There are expectations that in 2019 the trend to installing solar storage batteries will continue.

The solar battery storage trend following the solar PV installation is growing rapidly. Batteries for energy storage usually have one of three chemical compositions. Lead acid, nickel cadmium and lithium ion. In time as the storage size of the VRFB technology is refined into the scale size suited for home solar as low as 8kW the use of vanadium redox flow batteries (VRFB) will increase into residential applications. VRFB are currently restricted to the commercial and utility sized applications.

The first types of batteries listed are more affordable. But, lithium-ion battery is the best battery storage for a solar panel system.

The batteries store the electrical energy in the form of chemical energy. During use the internal reactions convert stored energy into electrical energy when required. In this battery, the positive and negative electrodes immerse in an electrolytic solution. That solution is sulphuric acid diluted with pure water. The positive electrode plate is lead peroxide. The negative electrode plate is pure lead in sponge-like condition. An external electrical load connects between these plates.

When we connect a load, the molecules of sulphuric acid is split into H⁺ ions and So₄^—ions. The hydrogen ions react with PbO₂ plate to form PbO and H₂O. This PbO reacts with sulphuric acid (H₂SO₄) and forms PbSO₄ and H₂O.

PbO₂ + 2H → PbO + H₂O

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PbO+ H₂SO₄→ PbSO₄+H₂O

PbO₂+H₂SO₄+2H →PbSO₄+2H₂O

SO₄ ions move freely in the solution. Some of them react with pure lead and give extra electrons to become radical SO₄ due to which it can’t exist alone and react with Pb to form PbSO₄. As H⁺ ions take electrons form PbO₂ and SO₄^- ions will discharge electrons to Pb plate, there would be a difference between the concentrations of two plates. Due to this there is a flow of current between two plates for balancing this inequality of electrons.

When we disconnect the load, the density of sulphuric acid falls, but hydrogen ions being positively charged move to the electrode connected with a negative terminal of DC source. They take one electron form that source to become a hydrogen atom.

These hydrogen atoms react with PbSO₄ to form lead and sulphuric acid.

PbSO₄ + 2H → H₂SO₄ + Pb

SO₄^- ions move towards the electrode connected to DC source. They give their extra electrons to become radical SO₄ and these radicals react with PbSO₄ to form PbO₂ and H₂SO₄.

PbSO₄+ 2H₂ + SO₄ → PbO₂ + 2H₂SO₄

They are:

Lithium-ion batteries are an advanced technology form of solar batteries.

Lithium-ion batteries are displacing the lead-acid batteries for solar storage.

The battery components exist in a container. To Charge the battery you connect an external power source. This causes lithium ions at the anode and electrons will move towards the cathode.

When we disconnect the external power source, the reverse process is able to occur.

When you connect an external load you complete the circuit. Electrons will flow through the external circuit. The ionized lithium atoms in the anode separate from their electrode. The lithium ions move toward the cathode through the electrolytic solution. Lithium ions combine with the cathode to become neutral.

Cathode Electrode Reaction:

CoO₂ + Li⁺ + e^- LiCoO₂

Anode Electrode Reaction:

LiC₆  C₆ + Li⁺ + e^-

Full Reaction:

LiC₆ + CoO₂   C₆ + LiCoO₂

In 2018, the lithium-ion rechargeable battery celebrated 27 years in production.

It's become the best battery storage for solar panel. The lithium-ion rechargeable battery has seen sales and growth over that 27 years. It has displaced many traditional batteries for solar storage. The lithium-ion battery is gaining popularity due to its high efficiency and lifespan.

This quality of lithium will lead to the growth of electrification storage. That will happen in homes and mini-grids as part of decentralized energy systems. But we will see it also go forward in cars and buses.

Lithium is the lightest metal with the lowest reduction potential. That makes lithium batteries superior to other batteries. Also, lithium is abundant in earth deposits and we can use it for another 400 years. The battery technology is cheap compared with other battery technologies.

The most popular type of lithium battery is lithium ion battery. It has an unbeatable combination of higher energy and power density.

Recent developments in batteries reflect that the lithium batteries are continuously improving. Their improvements in energy, safety, power capability and cost mean a long future for lithium batteries. The price of lithium-ion batteries will continue to fall in real terms and its power density will increase by 20%. 

With the ongoing concern for global warming an investment in a Solar PV system is an environmental one. These changes to battery price and efficiency will further add momentum in the field for using Lithium-ion in electric vehicles and storage of solar generated power. That will mean support continues for investing in Lithium-ion as the best battery storage for solar generated power.

References:

http://www.homeandenergy.com.au/buying-tips/choosing-battery-system/

http://energyinformative.org/benefits-of-solar-panels/

https://www.solar-facts.com/batteries/battery-choice.php

http://sustainable-nano.com/2013/10/15/how-do-lithium-ion-batteries-work/

http://sinovoltaics.com/learning-center/storage/lithium-ion-batteries-used-solar-systems/

https://medium.com/solar-microgrid/battery-showdown-lead-acid-vs-lithium-ion-1d37a1998287

https://www.electrical4u.com/working-of-lead-acid-battery-lead-acid-secondary-storage-battery/

http://pvcdrom.pveducation.org/BATTERY/operlead.htm

https://circuitglobe.com/lead-acid-battery.html