  A quantum battery is a device where an energy is charged by using a quantum
effect. Here, we propose a quantum battery with a charger system composed of
$N$ qubits by utilizing a collective effect called a superabsorption.
Importantly, the coupling strength between the quantum battery and charger
system can be enhanced due to an entanglement. While the charger time scales as
$\Theta\left(N^{-1/2}\right)$ by applying a conventional scheme, we can achieve
a charging time $\Theta\left(N^{-1}\right)$ in our scheme. Our results open the
path to ultra-fast charging of a quantum battery.
