x2 on what what was written above.
Carry a jumper pack and always keep it fully charged. Do not use it as a house battery. Pretend it does not come with a ciggy plug receptacle.
When your existing engine start battery is too compromised to trust, get the biggest marine battery which will fit in the same location, and consider an AGM battery from Odyssey or Northstar, as these have no issues accepting everything ( and more) that the alternator can make, and will also be able to start the engine when depleted to a lower level than the same size flooded marine battery could.
Northstar batteries are relabelled and sold as X2 power by Batteries +, a nationwide chain, and come with a 4 year free replacement warranty.
I've been cycling a Northstar group 27 for 3 years now, and recharging it somewhat close to ideally. Well over 400 Deep cycles on it and it is performing very very well. When new its engine cranking ability was scary fast. now it is still more impressive than any flooded battery of the same size/weight, but lost some of that extreme starter motor cranking gusto it had when new. For the last 18 months, it has been my only battery, for both house loads and engine starting. i have full confidence in it, and do not carry a jumper pack.
If one wants more amps from the alternator, add a parallel cable from battery (+) to alternator (+) stud (fuse near battery to protect cable, and add another ground cable from engine battery(-) to alternator mounting bolt on engine.
I recommend one does not idle unmoving to recharge a well depleted battery, as the low alternator rpms and lesser underhood airflow will heat the alternator much more than highway speeds and and highway rpms.
220f is the tipping point which will significantly reduce the life of the alternator, no matter its rating, or marketing, or possible chroming.
Also, if one has the option to plug into the grid and recharge, every so often, by all means do so as it takes a significant amount of time to fully recharge any lead acid battery, with ideal voltages. Rarely does the vehicle's voltage regulator even approach Ideal voltage for the required time on a depleted battery. Getting it back to 100% full when plugging in can easily double the life of the battery, compared to expecting the high amp rated chromed and polished well marketed alternator alone to do it.