I would not use blue Loctite on a battery connection. Loctite is a liquid polymer, and polymers are electrical insulators. The last
thing you want to do to the connection upon which your entire bike's current handling capability depends is to add insulation. It forms a high resistance connection, and resistance = heat, which = reduced current handling, shortened battery life, dimming lights at idle, etc. In the 35 years I've been riding and working on my own bikes, I have always used an electrically conductive anti-sieze (like Noalox) + a good old-fashioned lock washer. I've never had a battery bolt come loose, my lights don't dim, and the batteries always last a good long time.
I know there are people who will say they've been using Loctite with equal success, but I have to believe that it's because they didn't coat all
the threads, and the untreated threads were carrying all the load current. In fact, even Loctite themselves do not recommend thread locker for electrical connections. Depending on the application, they say to use Loctite® Dielectric Grease or Loctite® Silver Anti-Seize Stick exclusively