Because with fast charging from empty to 80 percent the battery generally doesn't take up to 1 hour.
But of course it's a little odd if the battery charging quickly only stuck at 80 percent of the battery capacity. It turns out that this is the reason that fast charging electric cars can only reach 80 percent.
Fast charging is limited to 80 percent of the battery capacity is required for safety reasons.
Below 80 percent, the electric power that can be absorbed can be above 50 kW depending on the strength of the fast charging device.
After passing 80 percent, the absorbed electric power will be cut to at least 10 kW and below. The stronger the incoming electric current produces higher heat.
If the battery continues to heat up to 100 percent capacity, its battery health quickly drops. For this reason, the remaining 20 percent of fast charging is limited to the cooling down process.
The battery is given the opportunity to absorb an electric current that is not too hot until it can be fully charged. The large amperage cut-off also keeps the battery charge cycle from being too high. High charging cycles will shorten battery life.