I'm planning to make a backup power system for some projects which runs on 5v. I have 12 Lipo batteries of 10Ah each. All the cells are brand new with <5 charge/discharge cycles each.
So I've attached all of them in parallel (1S12P; 3.7v, 120Ah) and used a boost converter to get 5v out.
Now the problem is when i try to charge the battery pack, it wont go above 4.04 ~ 4.06v. The charger would charge for hours and hours at 500~700mA. But battery voltage doesn't go up.
Its not the charger fault, I've tried 2 other chargers and get same result. I've also tried to disconnect the boost circuit and charge but it didn't help either.
However if i charge each cell individually then they get to 4.20v easily.
Now as u have guessed, its not possible to charge every single cell individually every time i have to charge the pack.
What am I doing wrong here? Why can't I fully charge the battery pack when they are in 1S12P?
Any suggestions would be highly appreciated
So I've attached all of them in parallel (1S12P; 3.7v, 120Ah) and used a boost converter to get 5v out.
Now the problem is when i try to charge the battery pack, it wont go above 4.04 ~ 4.06v. The charger would charge for hours and hours at 500~700mA. But battery voltage doesn't go up.
Its not the charger fault, I've tried 2 other chargers and get same result. I've also tried to disconnect the boost circuit and charge but it didn't help either.
However if i charge each cell individually then they get to 4.20v easily.
Now as u have guessed, its not possible to charge every single cell individually every time i have to charge the pack.
What am I doing wrong here? Why can't I fully charge the battery pack when they are in 1S12P?
Any suggestions would be highly appreciated