The invention discloses a composite battery comprising a battery shell, wherein a positive terminal and a negative terminal are arranged on the battery shell; a matrix battery, a super 
capacitor and a 
voltage-sharing circuit board are also arranged in the battery shell; the matrix battery, the super 
capacitor and the 
voltage-sharing circuit board are in parallel connection and form electric connection; a positive terminal and a negative terminal on the 
voltage-sharing circuit board are respectively electrically connected with the 
anode and the 
cathode of the super 
capacitor; the 
anode and the 
cathode of the matrix battery are correspondingly and electrically connected with the positive terminal and the negative terminal on the battery shell; and the matrix battery can be a lead-acid battery, a 
lithium ion battery or a 
nickel-
metal hydride battery. The composite battery has the advantages of 
high energy and power, low 
temperature resistance, matrix battery protection, long service life, 
energy recovery, energy saving and emission reduction, and 
resource saving, and is applied to electric starting systems, 
electric drive systems, uninterruptable 
power output, the starting of tractors and the 
recovery of the 
brake energy of motor vehicles. The preparation method has the advantages of simple process and low cost and is suitable for preparing the composite battery of industrial production.