The invention provides a construction method of a low-internal-resistance
lithium ion battery based on a
graphene-
carbon nanotube three-dimensional conductive structure, which comprises the following steps: step 1, preparation of a three-dimensional conductive
composite material: preparing the three-dimensional conductive
composite material from
graphene oxide (the thickness is 0.8-1.2 nm, and the number of
layers is less than or equal to 3), carboxylated carbon nanotubes (the
tube diameter is 20-50nm, the thickness is 0.8-1.2 nm, and the number of
layers is less than or equal to 3), and the
graphene-
carbon nanotube three-dimensional conductive
composite material is The preparation method comprises the following steps: mixing the raw materials (the length-
diameter ratio is greater than or equal to 500) and conductive
carbon black (the DBP
oil absorption value is greater than or equal to 300cm < 3 > / 100g) according to the
mass ratio of (1.5-3): (1-2): (0.5-1), and performing
argon protection treatment in a
ball mill with the
power density being greater than or equal to 200W / L for 2-4 hours to form a premix; the electrochemical performance is improved, the overall
internal resistance of the battery is smaller than or equal to 8 m
omega (the traditional battery is larger than or equal to 20 m
omega), the 5C
discharge capacity
retention ratio is larger than or equal to 88% (the traditional battery is smaller than or equal to 70%), the
mass energy density is larger than or equal to 320 Wh / kg, the volume
energy density is larger than or equal to 750 Wh / L, the capacity
fading after 2500 times of circulation is smaller than or equal to 15% (the traditional
silicon-based battery is smaller than or equal to 500 times), and the 1C
discharge capacity at-20 DEG C is larger than or equal to 85% of normal-temperature capacity (the traditional battery is smaller than or equal to 60%). The
lithium ion diffusion coefficient is greater than or equal to 1 * 10 <-10 > cm < 2 > / s.