There are several options:
1) Leave the (batteryless) Plus on 24/7. Then you only lose settings in the event of a power outage.
2) If you feel guilty about the power consumed with strategy 1), and can't/won't replace the battery, you could substitute a large capacitor for the battery. A ~1F capacitor would probably hold your settings for a week or more (although I admit that I've not actually tried this), and capacitors in that range of values seem to be relatively common these days. So, if you do use the Plus regularly, but don't want to leave it on 24/7, a batteryless solution might be acceptable (and would be more or less permanent).
3) Retrofit a three-cell mini battery pack, such as those found in many cordless phones. They seem to be widely and cheaply available.
1) Leave the (batteryless) Plus on 24/7. Then you only lose settings in the event of a power outage.
2) If you feel guilty about the power consumed with strategy 1), and can't/won't replace the battery, you could substitute a large capacitor for the battery. A ~1F capacitor would probably hold your settings for a week or more (although I admit that I've not actually tried this), and capacitors in that range of values seem to be relatively common these days. So, if you do use the Plus regularly, but don't want to leave it on 24/7, a batteryless solution might be acceptable (and would be more or less permanent).
3) Retrofit a three-cell mini battery pack, such as those found in many cordless phones. They seem to be widely and cheaply available.