Mine sits in the garage for months at a time, and starts fine.
A month ago, wife left the key on and the lights drained the battery.
I have this
Amazon.com
I connected to battery, and drove around for about 30 minutes. It’s been fine since.
BTW, I also love this product to fill tires with air every 6 months.
My tires should be at 36 PSI, some were under 20.