Clearly you get the Idea that they should all be matched and date coded. If not, the weaker will become parasitic of the other, reducing the total array to the weaker level ( that's the way I understood it anyway )
I'm guessing that at 1.5 years, the existing have already diminished somewhat.
For the roughly the same $, you could start adding 100 watt solar array and just recharge what you got.
Could you? Yes you could, and you would have greater Amp hours, just not optimal, and it may reduce the life of the new battery
Just my .02
Jim & Kim from Colorado
2014 Eagle 30.5 RLS
2015 Dodge 3500HD SRW 6.7L
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