Panasonic is now off my list for batteries, I had already stopped using Duracell and Energizer a while ago then switched to Panasonic and GP disposable primary cells.
I bought a few packs of Panasonic AA's about 6 months ago from a major retailer in the UK, they came off a large Panasonic display stand and absolutely no way they would be counterfeit.
I noticed a few weeks ago some were leaking in a fresh pack. I tested about 20 of them with a multimeter and the voltages were all over the place, only 3 were near the correct voltage. I ended up throwing them out.
Then this week I go to get an AA battery out of another pack in a drawer and it's leaked everywhere! these have an EXP Date of 2032.
I now need to go all over the house and workshop to find where I've put about 40 of these batteries. I think there might be some in the attic in Christmas decorations as well.
That's the last disposable AA, AAA or 9V cell/battery I ever buy, I'm going to pop in Ikea and stock up on some more LADDA for everything that will take a AA or AAA.
I've got 20 or more things in the workshop that takes 9V batteries, including 4x Fluke multimeters, so I've bought some 9V EBL Rechargeable lithium batteries to try out, if they work okay in everything I'll buy more, if some devices are fussy I'll get some 9.6V NiMH batteries.
I really don't think any Alkaline battery can be trusted these days, with all the reformulations and removal of "nasty" chemicals and elements.