Edouard, well, I hope the new board does the job. But if I may offer another possible solution??..
I'm in Indiana and from Octember to January, we are socked in with cloudy skies, and my ISS gets very little solar charge time. I am also running an old ISS that has been out there for over 8 years now. I don't have any extra sensors on the ISS and it's one of the wireless versions. I also have had issues this time of year, or rather as soon as the night time temps start to fall under 20?F, which still won't be for another month or so. This Winter is predicted to be very cold with little precipitation, so I'm looking at the battery freezing again.
A brief history of batteries: My Uncle, who worked for P.R.Mallory (they became Duracell) in research and development from WWII until he retired in the late 90s was always a good source of information about batteries and what they did, specifically how they did in different environments. He always told me to check the environmental specifications of the batteries I used if there was a problem with outdoor use. These are lithium batteries and this type of battery was designed to work with a generally fixed constant low current drain over a very long time period, perfect for the ISS as a rule.
Over the years I have ordered or bought locally the 123 batteries from wherever I could find them. And usually each time I would end up with a different manufacturer's product. So here's what I found looking back, a lot of battery manufacturers have a lot of differing temperature specifications and only a few are made with sub-freezing temperature specifications. And some just don't hold up in the cold. The most expensive 123s I found didn't hold up, and the cheapest didn't hold up when they got cold. The voltage drop often fell below 2v on a brand new battery after it got frozen once. The best battery I have found was the Duracel Procell PL123BK (12pack from Amazon, and usually inexpensive). The operational temperature range for these batteries is -20?C to 75?C (-4?F to 167?F). So far these batteries have outlasted anything I've used (including the direct replacement from Davis). You just need to pay attention to the manufacturers temperature curves.
I used to swap out my ISS batteries in December, but so far, haven't for the last three years on the Duracells. Time will tell. Also, when you change your batteries, wipe off the battery terminals with a little bit of alcohol to clean the contacts, it helps a lot.
My view on things, hope it helps a little.
Good Luck
Doc