u/Trexity

I have a reproduction pokemon blue cartridge and it has voltage drop issues while saving and music cuts out , batteries were almost dead in my console and I went to save which dropped the voltage and the console lost power . This resulted in my save being deleted, my question is how can I modify this to have this save using a battery when I solder it in? Is there anything I can do to make this happen ? I plan on flashing a retail unmodified pokemon blue ROM and adding a battery would that work?