My advice to anyone on the island who is considering lithium batteries; the paramount concern is what type of inverter/charger you will be using.
Lithium batteries in a very short time are Becoming Common place for energy storage in either back up and or money saving applications I.E. using the energy to offset peak and off-peak Electric rates. The typical inverter/chargers you find on the island are Clydesdale work horses that have proven useful for many years. That proven reliability comes with several trade-offs and these are modified sine wave, and the fact that they are usually set up for lead acid batteries. If you are considering lithium batteries I would strongly advise that you make sure your inverter is capable of charging and discharging lithium batteries.
When considering lithium batteries you'll usually come in to two categories and those are lithium ion and lithium iron phosphate 'Lifepo4' the latter of which is becoming the preferred chemistry of the two. lithium ion is the powerhouse chemistry it is a more energy dense chemistry and it is the chosen one when it comes to portable electronics i.e. laptop batteries cell phone batteries etc. on a larger scale you'll find set chemistry in electric cars as well as tesla power wall's.Lifepo4 is the newer kid on the block the advantage it has over lithium ion is Cycle life, (how many times you can charge and discharge)
many Lifepo4 batteries are coming in anywhere from 2000 as high as 5000 cycles, which if you only cycle once a day you are looking at 5000 days which is however many years. Both chemistries have a higher discharge rate than lead acid and or gel. Whereas typically it is recommended to never discharge below 50% for lead acid some lithium battery manufacturers are claiming 0% discharge (which in my opinion is BS and marketing ploys) but nonetheless the discharge rate is much higher than lead acid which in turn allows you to buy a smaller amp hour capacity.
one of the most important factors anyone who is considering buying lithium batteries should consider; SAFETY. of the two chemistries Lifepo4 is hands-down the champion when one talks from a safety standpoint. We all remember a few years back seeing these cheaply made electric scooters catching fire under the Christmas trees, those were from cheaply made lithium ion batteries with subpar BMS"s ( battery management system)
Without getting too technical this is the brain of the battery which disconnects any load on the battery when it is either overcharging or under charging, once that threshold is met you were BMS will disconnect the battery thus preventing the battery from being either under charged or overcharged both of which are harmful to the batteries, shortening lifespan and worst case scenario catching fire.
So in closing if you are in the market for lithium batteries, the two main culprits are lithium ion and Lifepo4,while there are many more chemistries,these two are the most common when one is considering energy storage for home use. That being said your most crucial step with these batteries is ensuring that your charger is set up for lithium (charge and discharge to recommended voltage by manufacturer) if you are in a position to withstand the blow of initial cost when it comes to lithium-ion then you are making a wise investment, remember whatever your lead acid batteries capacity may be, it is actually half if you are discharging according to manufacturers suggestion. And if you are not, then you are exponentially reducing cycle life of said battery. That in my opinion is why lithium is King.