Thank you for your kind offer of help.
I do have 2 keys, and the method you advise in the 1st para is what darwendosser suggested, and will be doing for me very shortly.
He thinks that after an hour running,
and repeating the procedure every week, I will not need to buy a new battery.
There is no urgency about getting it running because I have no need or desire to go out until a rescheduled chiropody appointment early in February - he will sort it by then.
On Thursday last I
did need it and ended up paying £10 in taxi fares

, which prompted me to, at last, do something about it.
I will be emerging from (semi)hibernation early spring and will be driving further and more often. This is the first winter that I have spent weeks on end without going out.
Hopefully by next winter I wont need to live like that.
I am moved by the generous offers of help I have found here on Accy Web.
Hibernation doesn't mean isolation when you have Accy Web friends
