Portable battery

I bought a battery I can easily carry around to charge my cell phone or tablet when there are no other options (ie no wall plugs, rechargin stations or car chargers). I more or less bought it on reflex, as it's been a long, long time since either of my devices has been in danger of depleting it's onboard battery when I was completely out of options. Also lately such options are more easily available.

Still, it can happen. For example, Interjet has no chargers onboard. On my recent drive to Oaxaca, the coworker who came along managed to wreck my car charger. Some airports, like CD del Carmen, have no recharging stations. So ti's a reasonable buy still.

My question is as follows: Once chargedm should I not use the battery at all until needed? or should I use it to recharge devices and then recharge the battery separately? I've read rechargeable abtteries do better long term when they're cycled.

Any thoughts?

This really depends on the type of battery. Of two that I know much about, it's this:

If it is nickel-cadmium, best to let it drain down completely, then recharge it fully. If it is lithium, that doesnt matter except you shouldnt use it when it's showing signs of being weak.

Note that most locations, including those that have charging stations, do not object if you plug a charger into their electric outlet. What's your electric use costing them? Half a cent?

Just make sure it's out of the way where nobody will trip on it.