Lithium iron phosphate
Background (from onboarding exercises)
NCA/NCM vs LiFePO4/LFP
LiFePO4/LFP is commonly called the iron phosphate
Has a nominal voltage of 3.2V per cell
Takes 16 of these cells to make a 28V pack while NCA/NCM only require 13 to hit that voltage
Is considered the most fire safe
Last about twice as long as the common NCA/NCM 18650-cell packs
A 4S pack of LFP is the most common replacement for a 12V lead-acid battery pack (4P x 3.2V = 12.8V nominal)
NCA/NCM in the 18650 format cells have a much better selection of choices and provide high power and long-range in a small package that is affordable
LFP can be found in flat pouch cells and 26650s and large cylindrical cells (these are big)
...
Li-ion VS LiFePO4
Specific energy of 90/120 watt-hours per kilogram, Li-ion is 150/200 Wh/kg
Discharge rate is much better (find numbers!)
1000-10000 cycles, Li-ion has about 500-1000
Li-ion lifecycle is more affected by the working temperature of the electronics/components whereas LiFePO4 can handle high temperatures with minimal degradation
350 day shelf life whereas li-ion only has about 300 day
https://blog.epectec.com/lithium-iron-phosphate-vs-lithium-ion-differences-and-advantages
Probably dont need need low temp capabilities?
Can be safely charged at -20 to 60 Celcius
Regular batteries: charging below 0 celcius - should reduce charge current (by how much?), will only suffer about a 10% loss in capacity when charging below 0, lead acid will lose 50%
These batteries has internal heating and monitoring systems to combat this and allow it to be charged down to -20 C