14-16v dc 10a+ booster from 12 to 16 v dc source

i am unable to think of any way to raise from a storage batt of 12-14 v, an output of min 14 v at min 10 a to charge a battery of 13.2 v installed in a portable unit . there is no ac available at the location . appreciate any info on this
thanks
antonio

If you use a battery of 7 gel-cells (14.7v) you will have sufficient voltage. You will need a series resistor to limit the initial current. Some 12 volt lamps in parallel will limit the current and give an indication of state of charge.

Have a look

maby you can use this with small changes

https://www.electro-tech-online.com/threads/how-u-all-know.9944/