  Quantum batteries are energy storage devices built using quantum mechanical
objects, which are developed with the aim of outperforming their classical
counterparts. Proposing optimal designs of quantum batteries which are able to
exploit quantum advantages requires balancing the competing demands for fast
charging, durable storage and effective work extraction. Here we study
theoretically a bipartite quantum battery model, composed of a driven charger
connected to an energy holder, within two paradigmatic cases of a
driven-dissipative open quantum system: linear driving and quadratic driving.
The linear battery is governed by a single exceptional point which splits the
response of the battery into two regimes, one of which induces a good amount of
useful work. Quadratic driving leads to a squeezed quantum battery, which
generates plentiful useful work near to critical points associated with
dissipative phase transitions. Our theoretical results may be realized with
parametric cavities or nonlinear circuits, potentially leading to the
manifestation of a quantum battery exhibiting squeezing.
