we may be talking two different battery sizes for 2.0 and QV. Idk if they are the same for both models. but the interstate that I posted is way smaller and lighter than the OEM in QV. I know when I swapped them. There was a considerable difference.
My mistake, as my records say that the stock high capacity Varta (I believe that is the European brand name for Johnson Controls) weighs 54 pounds, not the 45 pounds that I was remembering.
Interstate says that the H7 battery is 80AH, which would make it worse than the OEM battery for the purpose described by
@rumifaizer .
Note that there are 2 different OEM batteries, depending on if you have the winter package or not (I think). IIRC one is 85AH while the other is 95AH.
Too bad LiFePO4 battery manufacturers have not yet gotten serious about making their batteries into a proper replacement for lead-acid. In particular they lack a pre-heat function (improves CCA) for starting and also lack the ability to divert charge current to a heating element when the battery core is too cold to take a charge without damage. LiFePO4 will only work reliably if you never park anywhere that goes below freezing. A 110AH LiFePO4 battery plus electronics weighs about 30 pounds and except for the temperature range issue would be a great solution to the originally described problem.
I believe that the Lithium-Cobalt batteries found in BEVs are even more sensitive to low temperature, but that (most?) BEV manufacturers have incorporated thermal management into their designs.
Note that deep cycle lead acid batteries should not be discharged below 50% of capacity and starter lead-acid batteries are even less tolerant of significant discharge. Such discharging will not cause an immediate failure, but will substantially shorten the usable life of the battery. In comparison (most?) Lithium batteries can be discharged to 10% of capacity remaining without loss of life expectancy, altering the meaning of the AH rating of the battery relative to real use.
Also checking, Trojan batteries now have new and improved deep cycle chemistry/internals that unfortunately is incompatible with using the batteries for starting, so they are a no-go for Giulia <sigh>. They have managed 10 more AH for a group 27 battery compared to their previous technology (which was already 10ah higher than the competition), plus improved life expectancy after deep discharges. Note that there is no magic AH chemistry here: their batteries are markedly heavier than the competition's same-size batteries (more lead, less dead space?).
