Download Video of the utility charger working perfectly well
A year 2 engineering student identified as Donald Iro, from the department of electrical and electronics engineering, Federal University Otuoke has invented an 80,000mAh power bank. The 80,000mAh power bank was built with 18650 Li-ion batteries.
The first process is sorting the batteries. I have to sort them to determine their Voltages, the reason is this, if you have two or more cells with a huge difference in their potential differences (Voltage). Chances are high that one may be fully charged before the other and may lead to overcharge and possibly explosion of the overcharged battery.
After sorting them and making sure the difference in their Voltages is not bigger than 0.3 or 0.5… then I connect them in parallel.
In making power banks, the cells are usually connected in parallel to boost the output current while keeping the voltage constant, across the cells.
The batteries are soldered with extreme caution as it’s a dangerous process. Soldering a battery can easily lead to explosion because the cells can easily heat up.
He also has a 64,000mAh power bank but due to poor soldering, it charges continuously due to loss of charges.