Lithium-ion batteries for storing more solar energy generated by solar panels
Lithium-ion Battery overview
Batteries allow us to be mobile with our power. We can now have electricity in a more compact and portable manner. But unfortunately, batteries can discharge very rapidly leaving us without our portable electricity. If you don’t have a good battery charger, the batteries are mostly thrown away and replaced with new ones. The problem with this is, this scenario is bad for the environment and each year, billions of old batteries are being disposed of. With the new rechargeable batteries on the market, this problem easily gets resolved and disposing of batteries decreased. Rechargeable batteries used in smartphones, Laptops, electric toothbrushes, electrical cars and portable music player devices, uses lithium-ion batteries. Lithium-ion batteries are one of the best battery types available and are constantly being improved to provide the most power without discharging too rapidly. Lithium-ion batteries was introduced around the year 1991. The chemistry which makes up lithium-ion batteries, was invented by Gilbert Lewis in the year 1912.
Problems with standard batteries
A battery is made from chemical reactions inside of a metal container or canister. If you connect both ends of a battery to a flashlight, the chemical reactions start to occur inside the battery. These chemicals are breaking apart and join themselves together thus, producing other chemicals. Therefore, a stream of positively charged ions and negatively charged electrons are generated. The positively charged ions flows through the battery while, the negatively charged electrons move to the circuit where the battery is connected to. This enables electrical energy to power the flashlight from the battery. The problem with this in standard batteries is, that the reaction of chemicals takes place only once and in one direction. Therefore, standard batteries usually can’t be rechargeable.
Batteries that are rechargeable
Different chemical reactions take place with rechargeable batteries. Chemical inside the batteries break apart in different manners compared to standard batteries. A rechargeable battery’s chemicals are reversable where a standard battery’s chemicals are just a one-time event. When a rechargeable battery is being discharged or used to power a flashlight, the chemical reactions move in one direction and the battery provides electricity. However, when the battery is charging, the chemical reactions move into the opposite direction and the battery receives electricity. These reactions of chemicals can occur multiple times in both directions. Therefore, a rechargeable battery or lithium-ion battery can offer you up to a 10-year lifespan. (If you take care of it).
How lithium-ion batteries work
Rechargeable lithium-ion batteries are made up of power-generating cells. Each of these cells have 3 components: a negative electrode, a positive electrode and a chemical named an electrolyte between the positive and negative electrodes. The positive electrode consists of a chemical known as lithium-cobalt oxide. New lithium-ion batteries consist of lithium iron as a chemical compound for the positive electrode. Carbon (graphite) is the chemical compound which makes up the negative electrode. However, this varies depending on the battery and manufacturer of the battery.
Lithium-ion batteries works similarly as standard batteries in a basic way. When the battery receives a charge, lithium-cobalt oxide, positive electrode loses some of its lithium ions. These lithium ions move to the negative electrode and stays there. During this process, the lithium-ion battery absorbs and stores power. On the other hand, when the battery is being discharged, the lithium ions move the other direction to through the electrolyte to the positive electrode. Therefore, generating the energy which will be used to power the lithium-ion battery.
In both scenarios, lithium ions move in the opposite direction towards the ions around the outer circuit. However, electrons do not flow through the electrolyte. The electrolyte acts more like an insulating barrier to electrons. The flow of ions and electrons are interconnected processes, which means, if one should stop flowing, the other one will also stop. If the battery discharged completely, the ions stops moving through the electrolyte, therefore, the electrons won’t be able to flow through the outer circuit. On the other hand, if you disconnect any device that receives power from the battery, electrons will stop to flow and also the ions. The battery will keep discharging even if no device is pulling power from it. However, the rate of discharge is very slow. Lithium-ion batteries consist of electronic controllers that can be used to regulate the charge and discharge of the battery. These lithium-ion electronic controllers, also prevent the battery from overcharging, too fast charging and overheating. These factors can be dangerous as it can cause lithium-ion batteries to explode.
How lithium-ion battery charges and discharges
The movement of ions is what makes up lithium-ion batteries. If the battery is charging, the ions move in one direction. If the battery discharges, the ions will move in the opposite direction. While charging, the lithium-ions move from the positive electrode to the negative electrode through the electrolyte. Also, the electrons move from the positive electrode to the negative electrode, but electrons go all around the outer circuit. At the negative electrode, the ions and electrodes combine and unload lithium. If the flow of ions stops, it means that the battery completed its charge. However, during the discharging of the battery, ions move back through the electrolyte from the negative electrode to the positive electrode. On the other hand, electrons also move from the negative electrode to the positive electrode but flow through the outer circuit. At the positive electrode, ions and electrons combine and lithium is unloaded. In the case that all ions have flowed back, the battery is empty or discharged and will require a recharge.
Lithium-ion battery advantages
Lithium-ion batteries are a much more reliable battery type compared to older battery types such as Nickel-cadmium batteries. Nickel-cadmium batteries are known to have problems where they seem to get more difficult to charge except if they’re fully discharged. This is also known as a “memory effect” of nickel-cadmium batteries. Although, lithium-ion batteries do not contain the chemical cadmium, thus, making lithium-ion batteries a better solution for the environment. However, this does not mean lithium-ion batteries should be dumped everywhere, it can still cause major environmental problems it is not exposed to in a proper manner. If you pick up a large truck battery or any large Lead-Acid battery, it can be very heavy for most people. On the other hand, lithium-ion batteries are relatively lighter compared to lead-acid batteries. JC Solar Panels recommend Lithium-ion batteries for solar configurations.
Lithium-ion battery disadvantages
If we compare lithium-ion batteries to fuel such as petrol, instead of other batteries, we can see that it has some drawbacks especially in a weight to weight and power to power comparison. Lithium-ion batteries have a much lower energy density compared to diesel or petrol. If we compare an electric car which uses lithium-ion batteries to a standard car using petrol, we can see that it can take hours for the lithium-ion batteries to recharge compared to the petrol car that can fill up in a few minutes. However, using lithium-ion batteries, you have a more economical car which also reduces our carbon footprint on the earth. One major disadvantage of using lithium-ion batteries is, if the battery is overcharged or overheats, it can lead to fires and explosions. Also, internal malfunctions in lithium-ion batteries may cause short circuits and can lead to thermal runaway scenarios where it can lead to fire or explosions. However, engineers solved this issue by using a built-in circuit breaker which is also known as a current interrupt device or CID. The internal circuit breaker eliminates the charging current if the voltage reaches a maximum. Also, it eliminates the charging current if the battery overheats or reaches a specific temperature that is too high.