Good question but it really depends on the charging technology. The newer chargers like those for docked laptops are designed to be on all of the time. I don't know about the PTR1 and 2 but after years and years, I confess I have forgotten how long I have had mine, I have definitely noticed a decrease in storage capacity but I think it is about the same for the unit I keep plugged in all of the time and the one that I only charge periodically. Frank -----Original Message----- From: ptr1-users-bounce@xxxxxxxxxxxxx [mailto:ptr1-users-bounce@xxxxxxxxxxxxx] On Behalf Of John Sent: Sunday, January 23, 2011 2:30 PM To: ptr1-users@xxxxxxxxxxxxx Subject: Re: charging I can tell you from experience that, with any rechargable battery, NEVER leave them plugged in all of the time. No more than 24 hours. ------------------------------------------------------------------------ --- To leave the list at any time, please write to <ptr1-users-request@xxxxxxxxxxxxx> with unsubscribe ptr1-users in the subject or the body. The list home page is at <//www.freelists.org/list/ptr1-users/>. --------------------------------------------------------------------------- To leave the list at any time, please write to <ptr1-users-request@xxxxxxxxxxxxx> with unsubscribe ptr1-users in the subject or the body. The list home page is at <//www.freelists.org/list/ptr1-users/>.