Different performance between 4680 battery vs 18650
In terms of size, 4680 battery vs 18650, 4680 battery has a (46mm x 80mm) dimension while an 18650 battery has a (18mm x 65mm) dimension.
the size is the difference. 21700 batteries are slightly larger than 18650 batteries.
FOR 18650 V=16532.1 cubic mm
FOR 21700 V=24232.95 cubic mm
FOR 46800 V=132884.8 cubic mm
The increase in the diameter and height of the 4680 battery has brought its volume to nearly 5.5 times that of the 2170 battery, but the increase in volume has greatly reduced the number of batteries required in the battery pack. For example, for chestnuts, under the same battery capacity, 18650 requires more than 7,200 batteries, 2170 requires more than 4,400 batteries, and 4680 only requires 950 batteries.
Voltage and capacity
Comparing a 4680 battery vs 18650 battery, both batteries have relatively high nominal voltages, usually between 3.2 – 3.7V for 18660 and 3.7V for 4680 batteries.
For their different sizes, their capacities are certainly differentds. Genereally speaking, a 18650 battery has a capacity reaching 5000mAh, while a 4680 battery is rated to have up to an estimated 8000mAh battery capacity.
The cycle life of a 4680 battery vs 18650 battery is considerably different with a 18650 battery having between 1500 – 4000 charge and discharge cycles while a 4680 battery has between 1000 – 2000 cycles depending on the nature of charging.
Due to the fact that 4680 batteries are currently only used in electric vehicles, they can be categorized as ternary lithium batteries and hence, have a relatively short cycle life. On the other hand, 18650 batteries can either be ternary or lithium iron phosphate, so the battery cycle life can reach a maximum of 4000 cycles.
Since the cell capacity of a 4680 battery is 5 times higher than previous battery models, it has a higher peak performance level. In comparing a 4680 battery vs 18650 battery, 18650 battery needs about 7000 cells is a standard electric car but a 4680 battery only needs about 1000 cells to provide the same capacity.
Although both batteries function in similar applications and have similar features, there are some advantages and disadvantages on using either 4680 battery vs 18650.
Advantage of 4680 battery
There is reduced cost of manufacturing a 4680 battery, this is because each 4680 cell has a bigger capacity. For example, for the same capacity of a battery pack, the quantity requirement of 18650 cells is bigger than 46800 cells.
According to manufacturers’ datas, we know that the capacity of 4680 is 5.5 times that of a 21700 battery. Further more, each 21700 single lithium battery contains more than 50% more energy than 18650. Thus, the capacity of a 4680 battery is nearly 8.25 times that of a 18650 single cell.
Thus, it is a good way to save money if you choose 4680 cells.
- LOWER INTERNAL RESISTANCE
There is a considerable reduction in electrical resistance within the cell of a 4680 battery which results in less heat build-up. And then it will reduce chances of overheating when in use.
We have mentioned in privious blogs about llithium battery thermal runaway. We have understood that, internal resistance is one of important factors which will lead a lithium battery thermal runaway.
Thus, for 4680 battery packs, the good quality of lower internal resistance decrease chances of safety problems
The 18650 battery has a large capacity which enables it to store enough energy to supply consistently over a period.
Yes, battery forum will determine battery capacity in a way. We know 4680 cell is famous for its “fat belly”–large size, thus 4680 cell holds more capacity.
Although battery size will not change energy densuty if their materials are the same.
When the 4680 battery is packed, a large number of auxiliary materials can be “cut off”. So a larger capacity battery can be placed per unit volume.
Therefore, in contrast of 21700, the 4680 battery can increase the range of the vehicle by 16%.
In all, the energy density and capacity of a 4680 battery are much larger and can supply more energy for a longer period.
For cylindrical batteries, a diameter of 46mm is the best choice for combining high energy density and high power density after repeated test and simulation. According to people familiar with the matter, Tesla plans to have a single battery capacity of 98Wh for the first generation of 4680 in 2022, 108Wh for the second generation in 2023, and 118Wh for the third generation in 2024.
There is a faster charge rate with a 4680 battery as each cell has less internal resistance and can build up and store electrons a lot faster and supply energy equally as fast.
Disadvantage of 4680 battery
- For now, there is a limited capacity in mass producing enough 4680 batteries. Currently, only Tesla produces the 4860 battery to be used in the launch of the Model Y electric car. Other battery manufacturing companies are still at least a year away from beginning mass production of the 4680 battery. Regarding Other leading battery manufacturers, you can read the article about the 4680 battery industry pattern, which not only compares 4680 batteries with 18650 and 21700, but also talks about which companies are currently deploying 4680 batteries.
Advantage of 18650 battery
- The 18650 battery has a relatively large capacity usually between 1200mAh – 3600mAh.
- These batteries also have a long battery cycle life reaching up to 4000 cycles which is considerably higher than that of regular batteries.
- 18650 batteries are regarded as high-performance batteries with a high level of safety when in use. They are non-toxic, have thermal resistance, reduced chances of short circuits and malfunctions. In a 4680 battery vs 18650 battery comparison, 18650 would make for an excellent alternative.
- These batteries also have no memory effect, low internal resistance, and high voltages ranging between 3.2V, 3.6V, 3.65V and 3.7V.
Disadvantage of 18650 battery
- One major drawback of the 18650 battery is that it has a relatively fixed volume and capacity. For years 18650 has been used in a fair but limited capacity which when comparing 4680 battery vs 18650, 4680 batteries offer a much larger capacity and energy volume.