Thanks Mark, I have been doing a bit of reading lately and getting the impression different chemistries can make quite a big difference. Our Votronic charger in the Teardrop van has a lithium setting at 14.6 volt charge and 13.8 volt float. I cannot alter it. It also has an alternate Li setting of over 15 volts charge voltage. When I rang AA Solar, they advised some Li batteries need this??? The article you linked to suggests otherwise, so there is some variability in information out there.
The specs for the Valence lithium are here:
http://www.cleanenergybrands.com/shoppi ... g_12_2.pdf
From the graphs, I interpret that the difference in available SOC between charging at 14.2 and 14.6 volts would be just over 10%. Have I read this correctly? If so, I have about 180 amp/hr available capacity at 14.2 volts (there are two at 100 amp hr) which gives me about 140-150 amp hours of usable capacity, giving a bit of a safety margin. On reflection, I think this still compares very favourably with 200amp/hr AGM batteries.
The batteries are designed to be controlled by a BMS, and have cables to link with a Can bus system. I am not going to go there. But I think I will put in a VSR to stop any discharge at a pre-set voltage - thinking about 11 volts at the moment. Not sure whether to do the same about overcharging voltage, instead hoping the controllers will do their thing, along with a bit of vigilance. Anyone any ideas on that?