Interesting what you find out when you do a few searchings, often - as is in the case here - your searches come up with unexpected results.
I know several list members have described a “Dead Battery” condition with their Olympus DM4 - the battery won’t charge - but this doesn’t necessarily mean that the battery has died it seems, hater there may be a bug in the Firmware that’s causing the battery not to charge using the AC Mains adapter. In such cases it seems the best remedy is to use an external battery charger to get the battery to a charged state and make sure the battery is never fully drained before attempting a charge of the battery from the recorder itself. Replacement batteries for these recorders - along with a separate charing unit - are readily available, the one I have can use either AC Mains - universal voltage - or Car Battery power through the use of the supplied cigarette lighter adapter. ********** Those of a positive and enquiring frame of mind will leave the rest of the halfwits in this world behind.