the all new "should we break in new Li-ion cells?" thread

I am curious about the need or purpose of Li-ion break in for brand new cells. I am quoting below the some comments/replies from the only two posts I could find at CPF concerning the idea of breaking in new Li-ion, and since they are older threads, and considering all the new chems, I feel an updated thread and comments is not a terrible idea.

ICR LiCo is getting less popular, but now IMR LiMn and INR LiMnNi and also hybrids are becoming popular, also LiFePO4.

Do the experts feel the same way as before, considering new chems and ridiculous capacities?

Take the example of a single new cell, whatever chem. Let's treat this new cell like it is royalty, and forget for a moment it only cost $5-$10, so is not deserving of our time and attention. How do we pamper this cell and ready it for heavy current use? Do we break it in with several (how many?) full capacity high current discharge cycles? Do we rest it for as long as it was in use? Do we charge it slow, and as it approaches termination, increase the charge to faster and higher current?

How do we make a new cell intended for high current discharge as happy as it can be, and last through as many recharge cycles as possible? By giving up the top 10% of charge, and the bottom half, and using the middle-ish of its capacity only? Or top it off, rest it, and take it to the bottom?

Can any achievable and recognizable advantage be had to treating new cells differently for a number of cycles? Any difference of treatment recommended with different chemistry or capacities (low vs. high)?

Or just don't worry about it?! Gamble away the $5-$10/cell on danger may care, and let loose, and just be happy?

Thanks, guys!


from 2006:

SilverFox said:

Hello Leef,

It can be beneficial to do a few 1C cycles on Li-Ion cells if you plan to use them in heavy current draw applications, however they are usually ready to go without needing a forming charge or break in.

4.2 volts is fully charged, 3.8 volts is good for storage and is what new cells come charged to. It sounds like your 3.8 volt cells did not charge.

Tom

Click to expand...

from 2013:

Cemoi said:

Hi all,

I'm about to be delivered my new ebike, fitted with the Bosch engine and the new 400 Wh battery. The user manual doesn't deal with a "break-in" process to be followed when the battery is new.
I've searched CPF/Flashlight Electronics - Batteries included, but found nothing about Li-Ion break-in, unlike NiMH break-in which is dealt with in many threads.

A Google search gave me two very different recommendations:

1. According to this page: it is recommended that you perform a "break-in" cycle consisting of three discharge/charge cycles to allow your batteries to reach optimum performance. This involves three complete discharges and three complete recharges.
2. Whereas according to the Battery Break-in Process section on this page: It is recommended to perform 5 to 10 cycles of low discharges followed by full charges. A low discharge would be drawing 1-3 AH or riding 2-5 miles without heavy loads. Since the cells will discharge at different rates, the first cell to reach the minimum voltage will trigger the detection circuit in the BMS, which shuts off power. The range will be low and the customer thinks they have a bad pack. By doing short cycles the cells have a chance to equalize and not get far out of balance. The BMS has a balancing circuit, but it does not have the ability to bring up a cell that is much lower than the others. They have to be kept within a certain range of each other. In addition, leaving the pack on the charger over night gives the BMS time to equalize the cells.

Who is correct? Three full cycles, or 5 to 10 "very partial discharges + full charge" cycles?

Click to expand...

HKJ said:

Generally you do not need to do break in on LiIon batteries, but some battery meters need a few cycles to calibrate the reading.

Click to expand...

HKJ said:

That is some wisdom that was valid for old types of batteries, not for LiIon.
Today you are seeing 3 different types of rechargeable batteries: Lead acid, NiMH and LiIon, the first two can benefit from some break in, but not LiIon.

There is a few things you can do to get the longest lifetime from LiIon batteries:
Do not leave the battery in a hot place.
If you run the battery down, recharge it immediately.
If you are putting the bike away for the winter, discharge the battery to half charge, before storing it in a cool place.

To learn more about batteries I can recommend: http://batteryuniversity.com/

Click to expand...

Hello Night.hoodie,

My current position is that you have done your homework and have picked a cell suitable for your application. Charge it up and use it. No break in required.

Tom

I've been on a search for lifepo4 cells to use in the 1L-1AA. The cr123 sized ones are huge failures, so I moved on to AA sized ones.

Bought a pack of Tenergy lifepo4 AA size batteries. The last AA sized ones were poor. One of the two pack died in a few charges. The other can be used but it's junk Nuon brand. So I've been charging and running the Tenergy ones down charging them multiple times to see if they will last. So far the Tenergy are very good. Run more than long enough on low for use and run on high just under 40 minutes constant. After the first run down and charge the run time increased a few minutes for every cell. They don't run as long as other chemistries but run very precise. A gain of a few minutes after a couple full run downs in a light tells me these cells run better after some sort of break in. Best part is I now have reliable 3V rechargeables. They charge to 3.7V and drop to 3.33 after a while. Then stay there. Same exact volts they came out of the package with.

Just an observation with them cells in that chemistry with that light. Nothing scientific like science saying bumble bees can't fly or anything like that at least

Boris74 said:

I've been on a search for lifepo4 cells to use in the 1L-1AA. The cr123 sized ones are huge failures, so I moved on to AA sized ones.

Click to expand...

That's surprising! cr123 is the obvious format for LFP cells since they're a direct replacement for cr123 primaries. Have battery makers really failed to put a viable LFP cr123 cell on the market?

Besides your "dual-fuel" 1L-1AA, what is the use case for LFP AA?

--flatline

Capacity might increase very slightly after break-in but it shouldn't affect anything else. Just get quality cells from the big four manufacturers and don't worry about it. Charge at the slowest setting you can if you're not in a hurry. My flashlight cells don't see a lot of use and abuse, but I go through about one 18650 per day with my ecig (this means one cell sits at full charge about 50% of the time). Charged at 500mA, cutoff voltage on the ecig is 3.4v. Had a pair of Efest 2000mah IMRs last about a year before they got to about 50% capacity. Been using the same pair of Sony VCT5s for about two years (so over 300 cycles each) now and whatever capacity loss they have isn't enough for me to notice. Same ecig and charger. Don't know if the difference is more due to the manufacturer or chemistry. I imagine most people's flashlight cells don't get anywhere near this amount of use, and probably don't sit at full charge for very long, and most people should see their flashlight cells last many years regardless of brand or chemistry.

SilverFox said:

Charge it up and use it. No break in required.

Click to expand...

Thank you. This is my intention, and I'm already doing so, more confident with your advice from experience. I posted as OP with Keeppower UH1835P IMR18350 (hybrid) cells in mind, and they are simply awesome, especially having been accustomed to the lower runtimes of the highly regarded AW IMR16340 cells. I'm very pleased with their performance, and did not give them any break-in to speak of, other than using them, one after another for their full capacity from rest for just a few cycles, only because I found their advertised 1200mAh capacity difficult to believe, even with HKJ's testing. But it's no lie; these dogs will hunt.

Boris74 said:

I've been on a search for lifepo4 cells to use in the 1L-1AA. The cr123 sized ones are huge failures, so I moved on to AA sized ones.

Click to expand...

idk what the "1L-" part of "1L-1AA" is referring to, so apologies if my response is off the mark.

Tenergy is a recognized name brand, but the recognition here at CPF seems to be one of disappointment. I think my desire was comparable to yours, but I opted to try Exell brand because they ship from U.S., and especially because they are inexpensive, $1.50/cell. My experience thus far using these in incan application has been positive, having gone through all the cells a few times, I am seeing a half-hour of runtime at 1.2A in the best of the bunch. They appear to be forgiving of some level of over-discharge. After inadvertent overdischarge, allowing rest and recovery to 2.5V, seem to charge and hold charge fine. I can't say how long they will continue to hold charge incurring such abuse, but so far, so good.

But my experience with Exell is double-edged. One of the 20x AA LiFePO4 was DOA, and discarded. I had also ordered, after realizing what size they are and the meaning of the name of CR123A cells, NiMH cells from Exell in 2/3A size for double-cell incan application. The cells are slightly shorter than CR123A (possibly because, I believe, CR123A cells include thermal protection, increasing their height a little, and this is unnecessary with NiMH), so I need a spacer to allow reach from spring to lamp-contact, to complete the circuit. My experience with these cells has been positive thus far in a month of giving them light duty, though I doubt these are LSD NiMH cells, and they're not advertised that way. They do seem decent, accept the higher amps of my application, keeping in mind they probably won't keep adequate storage charge for more than a few weeks. The idea here is to eliminate all safety concern for multi-cell application, and I'm pleased they work for my purposes, though fully charging them takes longer than I expected. I had also ordered Exell 1/2AA NiMH cells for the same reason, and also Exell 4/3A NiMH cells (for carefree uber-capacity low-light application). Though Exell claimed to ship, tracking showed they never made it to the USPO, and thus never arrived. After a month, I requested a refund, and was immediately refunded for the 4/3A cells, but initially denied refund for the 1/2AA cells, and also accused of subterfuge. After another correspondence correcting Exell customer service's mistake of claiming the cells had arrived (they mixed up their tracking, thought the 1/2AA cells arrived but it was the 2/3A cells they were tracking), they finally refunded the rest of my money. So though I never got to experiment with these last two cell sizes, my money returned, all's well that ends well. But I recommend if any decide to use Exell, keep meticulous record of your transactions, just in case. Sorry so many words skewed to the topic of whether to break-in Li-ion cells!

flatline said:

That's surprising! cr123 is the obvious format for LFP cells since they're a direct replacement for cr123 primaries.

Click to expand...

Perhaps others can confirm, but I do not believe this to be true. Primary CR123A are 3V, may be 3.3V new and 2.5V depleted, but under load they apparently ride closer to 2.5V even if fresh. LiFePO4 secondaries are 3.7V fresh off the charger, ~3.4V rested, and IME hold their voltage under load much more resiliently than CR123A primaries, at least as high as 3.2V until depleted, again, just in my experience.

flatline said:

Have battery makers really failed to put a viable LFP cr123 cell on the market?

Click to expand...

I don't know of any direct secondary rechargeable replacement for CR123A primaries. But my understanding, gained from scraping CPF threads, and manufacturer recommendations, is that LiFePO4 16340 cells are safe in most single cell LED application, if the driver can handle the higher voltages, but are inappropriate and possibly dangerous in higher amp application, such as incan. This seems to have more to do with the geometry or volume of 16340 cells, and larger LiFePO4 cells, 18650, 18500, and 14500, will be more resilient to higher amp loads. I am not any authority on this matter, but this is what I have gleaned from the testimony of CPF members with better understanding and the warnings of manufacturers. The impossible to find AW brand LiFePO4 16340 cells are the rare, if only, exception, and presumably can handle higher amps of incan application.