For BFL13 et al... FLA vs AGM vs Li vs heated Li

pianotuna wrote:

theoldwizard1 wrote:

pianotuna wrote:
What about hot weather testing? Damage on LiFePo4 starts at 86 f, and they should not be charged when the temperature is 113 f.

Lead acid batteries don't like prolong high temps either. Definitely shortens their life.

True, however lead acid can be used at 140 f and charged at 120 f--that's a far cry from 86 to 113 f for LiFePo4. There is no question that higher temperatures reduce lifespan.

However, does the BMS for the LiFePo4 shut down charging at 113 f?

The bms will do whatever it's programed to do. Can't speak for every manufacturer out there but here is an example of mine.

GBS Elite CPU/ EMS will disconnect the charge source or loads.
**Over voltage (highest cell is over 3.8V after a 3 second delay)
** Under voltage (lowest cell is below 2.8V after a 30 second delay)
** Over current (current exceeds 10C for 10 seconds)
**Over temperature (highest cell exceeds 150°F or 65°C)
**Under temperature (lowest cell is below 32°F or 0°C, charging is not allowed)
**Ground fault (There is a high voltage leakage greater than 2mA to the chassis pin)
**Unmanaged cells (The programmed number of cells does not equal the number of cells read)

I have been in temps from near 0f to 115f degrees. Reviewing my notes for the past years my highest cell temp has been 84f even when the front compartment was in the mid nineties. Cell temps rise and fall from morning to night and not drastically as one would think by reading comments in posts. From my experience I'll see cell temp rise when charging at 100a after a couple hours and when nearing full before switching to absorb stage, once this period of time completes the cell temps actually cool down some not hang at the high temps.

There are somethings with lfp a person should be aware of and if proper homework is done and common sense is used a person should be able to enjoy the benifit of lfp, they are not faberge eggs some make them out to be.

Quoting web pages isn't really homework unless they have their source posted to see where they're getting the info from. White page as best but then that takes time. Most folks like to be spoon feed and then take it a gospel. ;)