Ok, I need to be educated about LiFe batteries. At this time I'm running LiPo batteries in everything after moving from SLA (too flipping heavy!) and like the performance I'm seeing. I've also read of people who have lost their houses/garage/workshop due to them combusting. I do the maintenance on them but would like to have some that don't require me to pucker-up every time I charge or use the batteries. Been looking at LiFe batteries for a little be, but I'm also looking at maybe going back to NiHms. My questions are: 1. My chargers are able to charge NiHm, Gel, SLA, LiPo and LiFe. Do I need a voltage protector for the battery or is that just when I run the batteries? 2. I've also seen LiPeP04. Is there a difference between a base LiFe? 3. What maintenance do they require annually/bi-annually? 4. From what I hear the chemistry is stable and robust. Is durability an issue? This is just a start for me. From what I saw at Nats and the different varieties of power systems at least lets me know I'm in the ballpark on things. Having a body that I've already got donated to science fiction I need to make things as simple/light as I can . Thanks, Eric
Lifepo4 is life. They're the same thing. LiFEPo4 is generally more stable than LiPo, but because it's more stable you don't get as much out of them in an instantaneous use case. Meaning a 10amp hour lifepo4 cell maybe has a 2-3c discharge rate, giving you 30~ amps to work with. Whereas a lipo could have a 50c discharge rate, giving you 500 amps. You may think this isn't a big deal, but in my experience most boats I've seen with lifepo4 batteries end up with voltage drop issues due to insufficient instant current capacity. All batteries are unsafe if handled incorrectly. Nimhs blow up like M80s, SLAs burn your house down with hydrogen. Lipo (and to a lesser extent lifepo4) will react very energetically if mistreated. Read that as violent chemical reaction/fire. Lithium batteries should always be kept at a storage charge, they should be discharged down to storage when not in use, and you should regularly balance charge them to ensure the individual cells don't end up out of balance with the rest of the pack. Which could result in 1 cell getting over/under charged and damaged. Lots of us use lipos. They're readily available relatively cheap and are the higher performance option. If treated properly, they are almost entirely safe. But use common sense. Don't charge when you're not around. Store at storage voltage. If possible, transport/store/charge in a fireproof lipo bag or some sort of reinforce fire resistant container. /End rant
I've use gellcell and SLA for many, many years and never had any real worries about them. To me there are bullet proof but unbelievably heavy and space consuming. So I have a level of comfort. I've seen a LiPo go up in several RC planes and have seen the issues they bring to the table. I like them due to the light weight and electrical punch they bring. I maintain mine in a fireproof lipo bag at storage charge, but am missing the ease of the SLA. Guess I'm getting lazy in my old age. I was looking for basically comparison/contrast and benefits of all involved. All batteries can go bang if not maintained or if there is a defect. You pretty much answered my question.
In my experience durability is a function of the brand. I have had excellent results with Turnigy Nano-tech batteries but every one of my ZIPPY brand batteries has failed. If you are buying large cells like used in ebikes or home/RV installs, try to get grade A cells. Grade B cells will be cheaper, but will not last as long. I have some 10 Ah LiFe cells that I have been running for 8+ years in my cruiser. They are currently at about 70% capacity. I suspect these are grade B cells, so it's not unexpected.
The red headway cells are the "high current" versions and will not normally have the low available current issue I was describing. I also have a few of those for any legacy 6v ships I end up owning before they get transitioned over to 3s/"12v". Check out batteryhookup.com they are a bulk surplus battery retailer that's right outside of Philadelphia and I have used them for a bunch of projects. They have those red cells for like five bucks each I think.
As Chris mentioned, I run the red 8ah headway cells in a 2S2P format for 16ah total.. Those packs fit into all of my larger ships and have proved more than sufficient to handle Seydlitz through NC. I've never put in more than 50% following a sortie. But I also don't run a crazy pump I've pretty much standardized on 2 of the blue hobbywing ezrun brushless motors for drive (3000kv iirc) with 2x hobbywing 10BL60 esc and then a simple brushed stinger on my pump. I bought those headways in 2020 to replace the old 20ah prismatic life cells that I'd been using since....2010 or so. LiFe has been very good to me over the years. Much better experience than the old SLA batteries to be honest. The only change that I'm planning on making to my life packs is to swap the balance connector from a JXT/JST style to a 3 pin XT style to deal with the pin corrosion from exposure to pond water. I'll make a separate adaptor to keep with the charger to go from the 3pin XT back to the charger's balance ports. I did have a Hyperion Eos 610i Duo charger (wore the poor thing out) that I used from way back (2008) and wore out. I replaced it with a Spektrum Smart 2100 charger a couple years back. Mainly went with the Spektrum over the Hyperion due to availability - the Hyperion gave up right before a Nats and the Spektrum was the best charger that was available to be delivered to the house overnight. No real complaints with it although I'd like it to put out a few more watts overall. Would go with a S2200 today if I was doing it again. The Spektrum is definitely nicer to travel with as it doesn't require a separate 12v power supply - nice small tidy package compared to the Hyperion stack. I run some 2S LiPos (Zeee 2S Lipo Battery 7200mAh 7.4V 120C on Amazon) for the cruiser. They have given excellent service over the years - better than any of my airplane lipos ever did. I don't do anything special with them aside from a bit of dielectric grease on the balance tap. They may get the same XT treatment as the Headway cells if that gives good service. Charge em, run the cruiser, then either re-charge for the next day or storage charge and into the fireproof battery bag between events. I do stand them up vertically post sortie with the wires down to encourage any water that might have made it into the hardcase to drain during the day before packing up and heading back to the hotel/house. I've also got a small 2200mah non-hardcase 2s lipo for the LST. It's only participated in 3 campaigns (1 in 2022, 2 in 2023) so long term performance is yet to be seen - so far good enough though and relatively inexpensive.