Lithium-ion batteries are a type of rechargeable batteries commonly used in consumer electronics. They have a high power to weight ratio, no memory effect, and only a slow loss of charge when not in use. The lithium battery was first developed in 1912 by G.N. Lewis but the rechargeable lithium battery was not commercially available until the early 1970s.
A typical lithium-ion battery can store around 150 watt-hours of electricity in a 1 battery of 1 kilo. A lead-acid battery can store only 25 watt-hours per kilo. Using lead-acid technology, it takes 6 kilograms to store the same amount of energy that a 1 kilogram lithium-ion battery can handle.
In certain circumstances Lithium-ion batteries can be dangerous and can pose a safety hazard because they contain, unlike other rechargeable batteries, a flammable electrolyte and are also kept pressurized. Although the risk is very low there has been concern about allowing Lithium-ion batteries to be transported by aircraft which could result in tragedy, a fire involving lots of them could destroy a plane. At present (2015) there is no adequate solution to this problem, about 4.8 billion lithium-ion cells were manufactured in 2013, and production is forecast to reach 8 billion a year by 2025.
It is likely that there will be important breakthroughs in battery technology involving lithium-ion battery’s which will enable a large reduction in the use of fossil fuels and nuclear generated power. A lot of the research and development has been encouraged by the electric car industry. Many improvements are starting to appear such as reducing the charge times and increasing the amount of charge cycles which affects the life of the battery.
A very interesting development in this field is the announcement by Tesla Motors in May 2015 of a new affordable battery capable of supplying power to homes or businesses. The price of solar panels has come down in the last few years so the price of actually generating electricity using solar power has come down to acceptable levels in comparison to electricity bought from the grid. The reason that solar power has not taken off in a big way is because of the price of electricity storage which until now had almost always using lead acid battery’s. The power generated during the day has to be stored for use during the night or at times of low sunlight.
The new Tesla includes the $3500 Powerwall, a home-based battery pack that can store 10 kilowatt-hours of power. That is like using a 1kw kettle for 10 hours. This would not be enough for heating but it could easily power a modern house fitted with led light bulbs and other efficient systems. The life of the battery is said to be 10 years. In a sunny country it would be possible to have free electricity for 10 years based on an initial investment of around $6000. For many people this would be cheaper than using an electric company.
The Powerwall batterys, – which are about 33 inches (0.8 meters) wide, 51 inches (1.4 m) tall and 7 inches (17.8 centimeters) deep — are designed to be easy to install, and will connect to the Internet so that users can monitor their power usage.
It seems that the change from centrally generated electricity to domestic and locally generated electricity is finally starting to become a reality. It will be interesting to see how this develops over the next few years.