After a bit of googling it would appear the
battery is expected to last approx 5 years although the figure of 7 is a possibility. Perhaps since we only use ours for a month or so each year we might expect closer to seven than five.
Most, if not all, of the tag firms seem to be interconnected, e,g, atmb are serviced by liber t, who seem to be linked to Emovis, who link to Sanef and bip and go. Etc.
Best answer seems to be that the
battery cannot be replaced by the user, it needs to be returned for replacement. Not very handy if you are abroad when it packs in. There do seem to be some locations where they can be swopped if I read the sites correctly. At least one tag supplier seems to indicate on your account page that the
battery is near expiry, as roaming rog stated. However if you are like me you may only look at the account intermittently.
Davy