Selling “glucose tablets” to people who may experience hypoglycemia has always struck me as an amazing piece of marketing. Perhaps only surpassed by selling people bottled water. Hey, if it’s in a special bottle with a special label then it must be better suited for its purpose, no?
Yes — the answer is no, not really. 
If you need glucose tablets while roaming about, look for any candy that has dextrose as the main/first ingredient and you’ll essentially be getting the same thing as what’s in the bottles … only in a possibly more palatable form, in my opinion. 
See, for example, this brief online comment from Gary Scheiner.
Certainly carry your tablets with you if they make you feel more comfortable. But I don’t think you would want to “waste” much space on items which you can easily purchase almost anywhere in the world if you need more.
By the way, how difficult is it to obtain those lithium batteries you wanted to take with you? Carrying a backup battery makes sense, but 8 of them? 
How many years do you expect to be living out of a suitcase? 
More seriously, what backup items and how many of them you take really depends both on the length of your trip and on what part of the world you would be travelling in. I’d pack differently for a remote village in a “less developed” country than I would for Paris.
When packing I think it is also important to plan ahead by thinking out how you might go about replacing something. Not that this is likely to happen, but it’s one way to prioritize so that you can carry more of what you are most likely to need and less of what you can probably easily replace while traveling should you need to.
For whatever it’s worth, here is a link to my version of the “backup” question from about three months ago.
Another version of this question was also asked in the discussion topic linked below.