That’s the power of FUD. You’re letting neoluddites who have never used these batteries and who are misrepresenting them to dissuade you from doing what you really want— and why? Simply because they are jealous they can’t afford them and think nobody else should have them either?
Disclosure: I have a 2017 RT 210PC equipped with an 800ah Ecotrek. I really appreciate the awesome capacity this setup affords. But that said, after 15 months, one of the batteries has failed and been replaced under warranty.
I suppose there is a contingent that refuses to enbrace emerging technologies simply because they are resistant to change - any change. But I hardly think this characterizes the forum contributors that harbor some doubt regarding lithium based batteries.
What your posts don't acknowledge are the trade offs necessarily assumed in choosing lithium batteries rather than AGMs for power management.
There are some clear lithium benefits like the great power density for weight, a high permitted depth of discharge and their awesome charging acceptance rate that facilitates rapid recharging of depleted batteries.
But there is a flip side:
These batteries are more vulnerable to wide temperature disparities than their AGM counterpart (which fully charged can withstand -40F temperatures with aplomb) and consequently current production lithiums require a complex battery management system that can implement heating and cooling to keep them within an acceptable temperature range for discharging, recharging and free standing. The high temperature limits have been quantified but what the free standing low temperature limits are is still a vexed question. Lithionics specifies -4F as the acceptable limit. Tesla has no problem with temps as low as -22F and Volta indicates that their batteries can sustain -40F without damage. While subtle differences in their respective chemistries may account for some differential, it doesn't account for the wide disparities cited by the various suppliers.
Another consideration is what respective consequences are involved if and when battery failure occurs. With the lithium setup, there first has to be an investigation of whether the symptoms observed are from the condition of the battery itself, the failure of its BMS logic or the failure of hardware such as a relay controlling a battery charging port. By comparison, the diagnosis for a failed AGM battery is simplicity itself. It took us over 16 weeks involving two visits from a mobile tech and finally a repair facility to address the lithium battery issue. To replace the same battery as an AGM would have been done in 16 minutes and capable of being accomplished most anywhere.