Can you charge smaller batteries on your newest charger? The one for the 4s

The connection of all batteries the same right

The gentleman at my local hobby shop said I always have to keep my batteries on the charger at store mode not sure, but I’m not gonna constantly have a battery with the charger on store 6:49 mode until the next time I bring out my XMAXX. Tell me this is not a true statement.

hello good evening, one question, can i connect a 6700 lipo battery to my traxxas ez-peak plus charger?

Can I leave a fully charged battery stored if I won’t use for a day or two or do I need to set store/charge? Also, when should I store batteries in bag? During charging/storing?