Solar panel for battary charging
Are okorder / or hook up several meters and supervise the process regularly. The UPS has no role in the charging—only the discharging.
What you are stating is that the battery you have will operate the UPS for about 2 hours before it is drained past the point of no return (technically 2.82 hours, but that would be a dead battery - most well-designed UPS systems cut off when the battery gets below about a 30% charge so that battery is not damaged. Lead-Acid batteries have about a 0%/month self-discharge rate if there is no load connected. The very best systems are as low as 3%, the worst are over 20% - and all at a 'normal' temperature. So, you will need a maintenance charger of about ten (0) watts or so - amp will be more than enough. And about any solar panel will handle that much with the proper charging connection.
Check the rating on the battery. Either look on the label, or look up the exact manufacturer's part number on the internet. There should be an amp-hour (AH) rating. It's very doubtful that the battery is 65 AH, by the way. When you get the amp-hour rating, people can advise you further.
