Advantages and disadvantages The LiFePO4 battery uses a lithium-ion-derived chemistry and shares many of its advantages and disadvantages with other lithium ion battery chemistries. The key advantages for LiFePO4 when compared with LiCoO2 are improved safety through higher resistance to thermal runaway, longer cycle and calendar life,I][URL="http://en.wikipedia.org/wiki/Wikipedia:Citation_needed"]citation needed[/URL][/I higher current or peak-power rating, and use of iron and phosphate which have lower environmental impact than cobalt. Cost may be a major difference as well, but, that cannot be verified until the cells are more widely used in the marketplace.I][URL="http://en.wikipedia.org/wiki/Wikipedia:Citation_needed"]citation needed[/URL][/I
LFP batteries have some drawbacks:
The specific energy (energy/volume) of a new LFP battery is somewhat lower than that of a new LiCoO2 battery. Battery manufacturers across the world are currently working to find ways to maximize the energy storage performance and reduce size & weight.
Brand new LFPs have been found to fail prematurely if they are deep cycled (discharged below 33% level) too early. A break-in period of 20 charging cycles is currently recommended by some distributors.I][URL="http://en.wikipedia.org/wiki/Wikipedia:Citation_needed"]citation needed[/URL][/I
Rapid charging will shorten lithium-ion battery (including LFP) life-span when compared to traditional trickle charging.I][URL="http://en.wikipedia.org/wiki/Wikipedia:Citation_needed"]citation needed[/URL][/I
Many brands of LFP's have a low discharge rate compared with lead-acid or LiCoO2. Since discharge rate is a percentage of battery capacity this can be overcome by using a larger battery (more ampère-hours).
While LiFePO4 cells have lower voltage and energy density than LiCoO2 Li-ion cells, this disadvantage is offset over time by the slower rate of capacity loss (aka greater calendar-life) of LiFePO4 when compared with other lithium-ion battery chemistries (such as LiCoO2 cobalt or LiMn2O4 manganese spinel based lithium-ion polymer batteries or lithium-ion batteries). For example:
After one year of use, a LiFePO4 cell typically has approximately the same energy density as a LiCoO2 Li-ion cell.
Beyond one year of use, a LiFePO4 cell is likely to have higher energy density than a LiCoO2 Li-ion cell due to the differences in their respective calendar-lives.
Powdered copper metal (Cu metal) is preferred for fires involving lithium and lithium alloys. Developed in conjunction with the U.S. Navy, it is the only known lithium fire fighting agent which will cling to a vertical surface thus making it the preferred agent on three dimensional and flowing fires.
Graphite-based powders are also designed for use on lithium fires. This agent can also be effective on fires involving high-melting metals such as zirconium and titanium.
It's not really that complicated, it's just something new that people are not used to yet.
audredger wrote: »
Do LFP batteries degrade like FLA if under charged? In other words, do the sulfate or something similar?
I'm thinking of my now 4 year old FLA's : 2,610 amps @ 24v that yields only 652 amps @ 24v (25% DOD) vs FLP's 800 amps @ 24v would yield 640 amps @ 24v (80% DOD). What if, I increased the FLP bank capacity to 1400 or 1600; Fully charge in the summer and only partially charged in the winter.... would they degrade with only partial charge for weeks at a time?
audredger wrote: »
I'll try again, do LFP's degrade (sulfate/phosphate) if left in a state of partial discharge?
RWB wrote: »
Here is a whole bunch of info on all the test that these Thunder Sky Cells go through. Its alot of them and they explain how they do it specifically.
RCinFLA wrote: »
In Thundersky link, it shows a 'belly strap and side support brace' addition. This was mentioned in a ebay advertisement to prevent anode to separator delamination. It may only occur at high charge/discharge rate but is disturbing.
Chuck46 wrote: »
So let me get this 8 cells for 24 volts a BMS or bypass shunt setup my outback charge controllor and I can have some batteries that last a long time need no water and dont do real wierd stuff in the cold. How much $$$$