Making solar charger work using capacitor?

I have a echo solar panel I am trying to charge a lawnmower battery with but the panel only gets the battery to ten volts. I want to use a capacitor to aid it in charging the battery. Looking at super capacitor but not sure how it works. could someone point me in the right direction or advice me?

What is the battery capcity? Type? Voltage?

What is the charger spec? What is the specification of the solar panel?

  Joined February 12, 2018      696
Monday at 02:11 PM