The invention provides a liquid active
magnesium-
cuprous chloride paper battery and a preparation method thereof. The
magnesium-
cuprous chloride paper battery is composed of the following successively laminated components: a
magnesium negative
electrode,
fiber paper having absorbed an
electrolyte, diaphragm paper coated with CuCl active
slurry and a carbon
current collector. The preparation method comprises the following steps: passivating the magnesium negative
electrode and preparing the
electrolyte with a
magnesium salt concentration of 0.1 to 1.0 M and a
corrosion inhibitor concentration of 0.02 to 0.06 M; dipping the
fiber paper in the
electrolyte and then
drying the
fiber paper at a temperature of 40 to 50 DEG C for subsequent usage; mixing CuCl, a conductive agent and an additive according to a
mass ratio of 80-90: 10-20: 0.1-1, carrying out ball milling to obtain CuCl mixed
powder, then weighing a certain amount of the CuCl mixed
powder, adding deionized water into the weighed CuCl mixed
powder to prepare the CuCl active
slurry, then
coating the CuCl active
slurry on the surface of the diaphragm paper and
drying the diaphragm paper at a temperature of 30 to 40 DEG C for subsequent usage; and successively superposing a layer of absorbent paper having absorbed the electrolyte, the diaphragm paper coated with the CuCl active slurry and the carbon
current collector on the surface of the magnesium
electrode, leading out positive and negative wires and carrying out vacuum packaging with a
plastic film. The liquid active magnesium-
cuprous chloride paper battery provided by the invention has excellent storage performance and does not lose
efficacy after long-term storage, and the
voltage of a
battery cell reaches 1.8 to 2.0 V.