Are Lithium Iron Phosphates gonna start replacing Lithium Ions?

The only reason I'm even asking is because I noticed that the Maxa Beam recently replaced their Lith-Ion battery with Lith-Iron Phosphate, and I was reading how the later is safer. So just wondering if in the future a lot of 18650s will be Iron Phosphates too?

First off, LiFePO4 IS a type of Li-Ion battery.

As far as whether LiFePO4 will replace other, more common types of Li-Ion batteries (such as LiCo or LiMn), I would say that it is not likely. LiFePO4 batteries actually have a long list of virtues compared to other types of Li-Ion batteries. They are safe, long-lived, have an almost perfectly stable voltage, can be charged quickly, and often have VERY high current capability. However, there are a couple of issues with them. First of all, capacity is low, especially with small form factor cells. It is uncertain whether this is something that can be improved. But if it can't, it will likely doom LiFePO4 to uses where low capacity or a physically larger battery is OKAY. And for flashlights, there is the issue of voltage. Because voltage is lower than LiCo and LiMn, a single LiFePO4 cell has problems delivering sufficient voltage to an LED (two in series work better). So at this time, LiFePO4 seems better suited as a lighter, more compact, and longer lived replacement for lead acid batteries rather than a replacement for lithium cobalt or lithium manganese batteries.

Now if we could have a 3.7V chemistry with the voltage stability, longevity, safety, and current capability of LiFePO4...........

Great points Matt.

The key issue is to match the battery to the application as you've noted - either type suited for the environment in use. And of course each can be abused.

Here is one application that is not really doomed to low capacity. Problem is I can't stuff it into my Fenix:

https://www.youtube.com/watch?v=oJ8AfJsOhsM

The other thing about voltage is to also match it to the environment. The nominal 3.2v lifepo4 makes an excellent replacement for most 12v requirements if used in a 4S configuration. Unfortunately, it is not a "drop in" replacement, and requires some tweaking to do it right.

Still, you are basically on target.

I have started using LiFePO4 cells in my "EDC" flashlights. Granted, my EDC needs are not very demanding, but I find the LiFePO4 are brighter and therefore more useful to carry around installed in my lights. (The increased brightness also provides a certain degree of "WOW factor" in comparison to NiMH.) When they grow dim, I switch to spare Eneloops which I also carry.



The tiny NiMH Shoshine charger (pictured above) is what got me interested. I have a number of "regular" protected and unprotected Li-Ion cells (14500 and 10440), but their need for increased "care" kind of turned me against them. So, I generally only use them for testing purposes. Therefore, I had decided to standardize on Eneloop "Black" (Pro/XX) in all my flashlights.

In any event, I was looking for a very small charger to carry on a daily basis, and found that the Soshine SC-F3 charger can recharge both NiMH and LiFePO4. According to HKJ's review, it is not all that great, but it can safely "get the job done" if you need a charger in a pinch. When I realized that it that could also charge LiFePO4, I got intrigued. So, I decided to give LiFePO4 a try for daily use. So far, I am very happy with the results.

I always keep an AAA TANK007 E09 on my keychain and an AA "Aleto" in my backpack. (The Aleto is a $5.00 flashlight, that can be considered a slimmer version of the infamous Sipik SK68 and its many clones.) I keep a regular supply of these flashlights on hand, because I sometimes end up giving one away.

Both flashlights perform very well on LiFePO4, and are (of course) significantly brighter at 3.2 volts. Granted, runtimes are not very good, but my usual EDC flashlight usage typically does not require a very long runtime. When I do need longer runtimes, I switch to the spare Eneloops which I also always carry with me, along with the charger.

I carry these two "cheap" flashlights because I have found them both to be completely reliable under normal use (so far, they have always provided light when I needed it) and due to their low cost, I do not worry about losing them, or not getting them back again, if I happen to loan one out.

I often use them in my CR2 lights that I EDC, which include a 4Sevens Quark Mini MLR2, a Nitecore Sens Mini, and a 4Sevens Atom mule. They're noticeably brighter though if I use a 3.7V 15270 battery, especially on high. But I prefer the extra safety of the LiFePO4 cells since no one seems to make protected RCR2 batteries anymore. Like Rosoku, my EDC lighting needs are modest so I don't miss the extra capacity. I recharge often, because I have so many Xtar MP2s small battery chargers scattered around that I always have one available to use.

StorminMatt said:

First of all, capacity is low, especially with small form factor cells. It is uncertain whether this is something that can be improved. But if it can't, it will likely doom LiFePO4 to uses where low capacity or a physically larger battery is OKAY.

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Bingo! You've totally cut to the chase right here in regards to my question, Maxa Beam IS indeed a use where a physically large battery is ok! There's my answer, thanks

I've been playing with them for a while and at 3.2v and they seem to be less risky as a drop-in replacement for primary lithium 3.0v or Alkaline 2x1.55v. A freshly charged Li-Ion can be a lot hotter than 3.7v

Mike

Arizona_Mike said:

I've been playing with them for a while and at 3.2v and they seem to be less risky as a drop-in replacement for primary lithium 3.0v or Alkaline 2x1.55v. A freshly charged Li-Ion can be a lot hotter than 3.7v

Mike

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Welcome to the forum!

magellan said:

Welcome to the forum!

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Thank you.

I am a huge fan of LiFePO4 technology. More power density than other Lithium Ion types, safer than SLA or Alkaline, excellent 2:1 voltage match for Alkaline and 2:3 for Lead Acid. I think the energy density advantage of Lithium Ion is going to keep them in tiny little sporty EV cars but I suspect that LiFePO4 is going to start dominating in the household and larger EVs.

Mike

Arizona_Mike said:

Thank you.

I am a huge fan of LiFePO4 technology. More power density than other Lithium Ion types, safer than SLA or Alkaline, excellent 2:1 voltage match for Alkaline and 2:3 for Lead Acid. I think the energy density advantage of Lithium Ion is going to keep them in tiny little sporty EV cars but I suspect that LiFePO4 is going to start dominating in the household and larger EVs.

Mike

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LiFeP04 does not have the energy density to be competitive for EV and certainly not taking price into consideration.

Range sells...

The LiFePO4 used by the Maxa Beam light weighs a pound more than the LiOn also used by the Maxa Beam light.

I called Annie the other day and got pricing for the LiFePO4. Found out that I also needed a new cable and charger.

The cost to make the switch to LiFePO4 was almost $500 for the package. Not bad, but not something for the faint of heart either.

Got to order another phase converter for the lathe, then I'll have some money freed up for the battery switch over.

In this market, I think LiFePO4 batteries are on the decline.
People value runtime over safety, even with explosive chemistries next to their head. Plus the risk factor with cobalt batteries seems to have been mitigated.

For me, I rather eliminate risk than mitigate it. I prefer LiFePO4, but they are becoming scarce/expensive. I'm now considering going back to NiMH.

My K2 Energy batteries (123A or 16340 size) have the most unbelievable charge and discharge curve. As they charge and discharge their voltage will sort of "flatline" where it just stays steady like no other battery I've ever seen. In case anyone is wondering, I'm using a DuraTrax ICE Intellipeak. A very nice charger. A little old now, but I swear I still can't find anything better.

I really like my K2 batteries too, but the availability/cost is making me turn.

Fast forward 18 months and high drain and safer 3.6-3.7 technologies have really matured. I suspect LiPO4 will live on long-term in stationary applications, E-vehicles will move to NMC in most non-performance cases (SUVs and trucks with plenty of room) and NCA in weight and size critical applications (sports cars, very compact cars, and bikes) and high vibration/shock environments (despite their danger). Park the Tesla outside :devil:

LCO, LMO, LMC, NMC, NCA, LFP, etc. are all named for their anode types. The fact is we have reached such a high level of cathode development that the carbon anode is a now a limiting factor. We could make >5000mAh 18650s right now with silicon anodes that would only be good for 10 discharges. Silicon undergoes a greater than 3x change in volume when lithiated--not a good thing for a sealed battery format.

Mike