Not sure I like the price tag on these batteries... has anyone delved into the calculations on their needs for their reef? I remember when they came out with lithium ION for power tools. Lets just say I'm still let than impressed... I could run circles around Lithium with the old nickel batteries they used to sell.
Keep in mind there are multiple Lithium chemistries and they have all gotten a lot better recently. I have a battery powered lawn mower and will never go back to gas. I can mow my entire yard on one set of batteries and it is a lot quieter.
LiFePO4 selling points are that it does not burst into flames, and will have 80% capacity after 3-5k charge cycles. Also, you can charge to 100% and drain to 0% without damaging the capacity. Doing the full 100-0% quickly and repeatedly is what can knock you back to 3k charge cycles. However, quickly is draining it in an hour, then charging it in an hour. LiFePO4 is also expected to have a 10-15 year life, maybe longer with less charge cycles.
The Lithium chemistry they use for a phone battery gets damaged by heat, and degrades when at 100%. This is why those ones don't last very long. They are more energy dense so they are smaller and run the phone longer to start with, but using your phone, or leaving it on the charger causes them to get damaged.
The Lithium chemistry They use, or used to use, in power tools is different and designed for very fast charge and discharge.
On top of all that, there is quality of the battery, and the system that manages it. With a LiFePO4 you get in a drop in form like BattleBorn or Relion there is a BMS in the case that controls the charge and discharge of the battery to make sure it does not get damaged.
Point being, not all Lithium batteries are the same. They all have different use cases and life expectancies. LiFePO4 is the one most people like due to long life and safety. LiCoO2 would be much smaller and lighter for the same energy, but would not last as long and I think it is one that can burst into flames.
