The lithium ion battery, also called Li-Ion battery, is a device designed to store electrical energy that uses a lithium salt as an electrolyte that provides the necessary ions for the reversible electrochemical reaction that takes place between the cathode and the anode.
The properties of Li-ion batteries, such as the lightness of its components, its high energy capacity and resistance to discharge, the absence of memory effect or its ability to operate with a high number of regeneration cycles, have allowed the design of lightweight batteries, small in size and various shapes, with high performance, specially adapted for applications in the consumer electronics industry. Since the first commercialization in the early 1990s of a battery based on Li-ion technology, its use has become popular in devices such as mobile phones, electronic agendas, laptops and music players.
However, its rapid degradation and sensitivity to high temperatures, which can result in its destruction by inflammation or even explosion, require the inclusion of additional safety devices in its configuration as a consumer product, resulting in a higher cost that has limited the extension of its use to other applications.
Advantages
- A high energy density: They accumulate much greater charge per unit of weight and volume.
- Low weight: With the same amount of stored charge, they are less heavy and occupy less volume than Ni-MH type and much less than Ni-Cd and Lead.
- High voltage per cell: Each battery provides 3.7 volts, the same as three Ni-MH or Ni-Cd batteries (1.2 V each).
- They have no memory effect.
- Linear Discharge: During the entire discharge, the battery voltage varies little, avoiding the need for regulator circuitry. This is an advantage, as it makes it very easy to know how much charge the battery is storing.
- Very low self-discharge rate: When we store a battery, it progressively discharges even if we don’t use it. In the case of Ni-MH batteries, this “self-discharge” can be more than 20% per month. In the case of Li-Ion it is less than 6% in the same period. Many of them, after six months at rest, can retain 80% of their charge. Due to the superior performance of the lithium ion battery, it is widely used in the manufacture of RV batteries.
Disadvantages
Despite all its advantages, this technology is not the perfect system for energy storage, as it has several defects, such as:
- Average duration: Depends on the amount of charge they store, regardless of their use. They have a useful life of about 3 years or more if stored with 40% of their maximum charge (in reality, any battery, regardless of its technology, if stored without charge, deteriorates).
- They support a limited number of charges: between 300 and 1000, less than a Ni-Cd battery and the same as Ni-MH batteries, which is why today they are beginning to be considered in the category of consumables.
- They are expensive: Their manufacture is more expensive than Ni-Cd and the same as Ni-MH, although currently the price drops rapidly due to its great penetration in the market, with the consequent lowering of prices.
- Worse cold working capacity: They offer a lower performance than Ni-Cd or Ni-MH batteries at low temperatures, reducing their duration by up to 25%.
Maintenance
These batteries have no memory effect, and therefore do not need to be completely discharged. In fact, it is not recommended, since it can greatly shorten its useful life. However, and despite not requiring special maintenance, like other batteries, they do need some care:
- It is recommended that they remain in a cool place (15°C), and avoid heat.
- When they are going to be stored for a long time, it is recommended to leave them with an intermediate charge (40%). Likewise, keeping them fully charged for long periods should be avoided.
- The first charge is not decisive in terms of its duration and it is not necessary to do it; the operation of a lithium ion battery in the first charge is the same as that of the following ones. It is a myth probably inherited from nickel batteries.
- It is necessary to charge them with a specific battery charger for this technology. Using an improper charger will damage the battery and may cause it to catch fire.
Lithium Batteries: Risks and Prevention
As more companies opt for 12v lithium battery equipment both in their forklift fleet and in the different elements of our day to day, more attention is also being paid to the possible risks. It is common to find videos of smartphones on fire on social networks. But what are the real risks of lithium-ion batteries and how can they be prevented?
