Low battery solution?

[beyond the blue]

My 3 year old ES has been in a body shop for the last 4 weeks so hasn't been run properly. I got it back 2 days ago and not run it since. This morning trying to start it l got multiple warnings and the headlights started strobing fast. Called the AA out who found the 12v Battery was low, he connected a booster and everything started fine. What kind of booster pack would l need to buy in case anything like this happens again? Not looking for anything fancy as l will still be with the AA.

[ColinBarber]

Doesn't need to be powerful. e.g.

https://www.amazon.co.uk/NOCO-GB20-UltraSafe-Lithium-Gasoline/dp/B015TKPT1A/ref=sr_1_10

https://www.amazon.co.uk/Starter-FLYLINKTECH-13200mAh-Portable-Flashlight/dp/B0C4GP2ZQH/ref=sr_1_5?th=1

 

[Sandandlime]

My ES doesn't get as much use over the winter as the rest of the year and this is, of course, when the 12v Battery suffers the most. To avoid such issues I attached one of these to the battery:

https://www.amazon.co.uk/CTE-56260-Direct-Connector-Adaptor-6-3mm/dp/B002MT72YE

It is readily accessible in the boot without having to remove the rubber protection mat and whatever I've left lying in the boot making charging a very simple task. Typically, I charge it once a week for a few hours and the Battery is always fully charged when I need the car.

After having a similar Battery issue I started monitoring it's charge state and was surprised at how much it reduced over a week.