I’ve got a lot of Lithium batteries. My power tools have them, some household appliances have them, and now our bikes have them. I don’t use them all the time and especially over winter months a few get ignored for a while - to their detriment. I’m loath to spend time once a month going round them all - charging them up all up to probably too much charge. Do they not have chargers available that you can leave connected to the battery, and it just periodically tickles them up to (say) 60% charge without drama, or attention required from me?