Dynabat lithium-ion cells - batteries with optimal characteristics
Cells, otherwise known as batteries. These are carriers of electricity that can be discharged and recharged.
The battery in any electric vehicle, be it an electric scooter or an electric car, consists of many cells connected together (small batteries).
The most common type of cell used in electric vehicles is the lithium cell -ionic 18650.
The name 'lithium-ion' comes from the fact that the battery operates using lithium ions.
18650 is due to the dimensions of the battery. 18 is the width of the battery in millimeters. 65 is its height in millimeters. 0 means the battery is cylindrical in shape.
Lithium-ion cells by their nature are characterized by a great weight to capacity ratio, hence they are used in all portable devices and vehicles.
The capacity of a cell is the amount of energy it contains.
Many customers do not even think what cells the battery in their vehicle is made of. It results from a lack of awareness. In our post, we will try to explain to you what a good cell characterizes, and thus a good battery (accumulator).
The complete specification of each 18650 cell consists of several A4 pages. We will describe some of the most important parameters and features in our post.
The basic parameter of a cell is its capacity , expressed in Ah, or Ampere hours. As the name suggests, the capacity tells you how many Ampere (how much current) can be released in an hour.
Cells usually have a capacity from about 2Ah to 3.5Ah, or expressing the capacity in mAh, or milliampere hours - from 2000mAh to 3500mAh.
Example: A battery with a capacity of 2Ah can give 2A (Amps) for an hour, or in a different configuration - it can give away 1A for 2 hours. Then kaput :) you need to load.
The second parameter is the cell's ability to release energy . This parameter is expressed with the letter C (Capacity). It tells us what multiple of its capacity it is able to give back the cell during operation.
1C batteries can give up to one-times their capacity. If the battery has a capacity of 2Ah and 1C, it can give away 2A.
2Ah, 5C battery, can give 10A.
Some 18650 batteries are able to give back as much as 10C. With a capacity of 2A, this is a current of up to 20A.
Cells that can release a large amount of energy at once are called high-current cells (because they release a lot of current at once - a lot of A).
Another important parameter of a cell is its assumed lifetime , which is expressed in charging cycles.
One full charge cycle, the cell is discharged to 0% and recharged to 100%.
The last parameter of the cell is its internal resistance which, in a simplified way, tells how much the cell resists against current flowing through it. The lower the resistance, the easier the current passes through the cell. Such a good flow of current is also accompanied by a small voltage drop on the cell (because we do not waste energy to push it through the cell).
After this long introduction, we can move on to our cells - DYNABAT cells , which we use in our electric scooters.
Dynabat lithium-ion cells, They are neither high current cells nor high capacity.
Our cells, however, due to the fact that they are not 'trimmed', have a low internal resistance and are long-lasting.
Cells are assumed to have 80% of initial capacity after 1000 charge cycles .
It should be remembered, however, that these are laboratory tests of a single cell. During such tests, the battery is discharged in optimal (pleasant) conditions.
When operating in a rechargeable battery, all the batteries work together and thus also heat up. Which adversely affects their service life.
In addition, cells working in a battery usually give off much more energy at a time than during laboratory tests.
Due to these factors, a battery (accumulator) composed of 18650 cells will not have the same number of charging cycles as a single 18650 cell in laboratory tests.
Added to all this is the way of taking care of the battery, and thus the depth of the battery discharge, storage, and also the method of charging.
These aspects will be described in a separate guide, which will be devoted to the care and proper use of the battery.
As Shift Seven, we assume that the batteries will last for about 500 full charge cycles. > After this time, we will feel a decrease in battery capacity, which will translate into a decrease in range. It is a few years of using the equipment.
Capacity, that is the amount of energy contained in the battery