I just received my new CCS with the 19.2 battery. I read this whole thread, and was at 1st convinced to do the "80/20" charge theory to prolong battery life. But then I did some math, and have decided to full charge "100/20"; I only plan on using my bike 7 months of the year when I am in Upstate NY; I winter for 5 months in Florida, and will not be taking my CCS. So if I charge fully to 100%, I can theoretically expect to only get about 400 cycles out of the battery. However, I also expect to get about 50 miles per full charge at the level I ride (I will still use 20% or 42V as my low "cut-off" level. ) 50x400=20,000 miles. I expect to ride about 2000 miles/ year. So that works out to , in theory, the battery still lasting 10 years. That's quite a long time despite the full charge! I haven't seen it discussed here, but what is the practical lifespan of the battery in terms of age (aside from charge cycles)? i.e Won't at least some of the 78 18650-type batteries inside start to leak at some point? Or the battery otherwise fail simply due to age? I have flashlites with these batteries, and cannot imagine them lasting 10 years without physical failure. Does anyone know if these batteries will last 10 years even if "properly" charged and maintained? The bottom line is that possibly a "coddled" 80/20 battery may in the end have no more longevity than a 100/20 charged battery; but the 80/20 charged battery gives up some performance that the fully charged battery does not. Am I off base here? anyone?
How to Best Charge Battery for Longest Life
- Thread starter Eglon
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- battery maintenance
Asher
Well-Known Member
I had the same question, after doing similar calculations. It's known as calendar aging. But the only info I could find was abstruse stuff in research journal, and a ten year old blog post from Tesla.
And how do calendar aging and cycle degradation interact? If you cycle a lot does calendar aging still have an impact in addition to the cycling?
I saw someone on here (not Juiced) say they had a backup battery that decayed just as fast as their main battery, purely from age.
I don’t think 18650 cells degrade with age . I remember reading that there were some lithium ion batteries with thousands of charge cycles on them with no notable degradation. The key is never to discharge the battery to 0% and to periodically balance the cells (which should happen automatically if you charge the battery to 100%.) Make sure periodically “top off” your battery to 49-50V in the winter. They don’t lose much charge but the consequences of running it to zero are that you kill it. I was talking to a original Cross Current owner who put his bike into winter storage (in Southern California no less) and killed the battery. He probably stored it with a low charge and it eventually drained to zero. Believe it or not, the dealer gave him a replacement battery under warranty.
Jeffrios
Member
Remember, at 400 cycles, the battery doesn't go from performing 100% to 70-80% instantally, its a gradual change, so after 200 cycles, you may be less than 90% of the performance. I would reconsider...
Here is a site with some evidence of battery charging:
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
Jeffrios
Member
I am going to do the same thing. I have a 25 mile round trip I am going to make on my 52V battery coming. According to the chart, I should be fine doing the 80-20 rule, but we'll see when I hit the road for real!
Chris Hammond
Well-Known Member
If I get my bike before you, I'll report on the performance of the 52V battery at 80% charge. My commute is 30 miles each way. My plan is to recharge at work to enable high speed riding. However, my first few commutes are going to be test runs on performance and range. I really don't want to buy a second satiator charger for work at $300. I have the option to use mass transit to assist my commute, so I plan to use it for a few days to assist me in testing.
Captain Walnut
Member
How would you connect this charger to the XLR battery port? Looks like a great option, much more affordable than the Cycle Satiator.
Suggest you check page2 of this thread; Thomas does not have much faith in Luna, per several of his replies...
Bruce Arnold
Well-Known Member
I think your original thinking is on the money. Don't let these guys sway you. This is an ongoing conversation on the forum, and of course we all think we're right, and we all have reasons to believe so.
I've done pretty much the same calculation as you did. Slightly different inputs, similar outcome. Here's how I've got it figured:
I charge the battery from 50-100%. This is not a full cycle, it's a half cycle. I have the 17.4 Ah battery, and letting it drop to 50% gives me around 50 miles of riding (mostly on Eco and 1.) If I get only 400 cycles doing it this way, that's 800 half-cycles, at 50 miles each, or 40,000 miles.
Yes, that assumes no degradation. In fact, over time I'll only get 47 miles, and then 44, and then 40. So maybe it will only be 30K miles, instead of 40K. Not a problem. I will have replaced this battery long before it is no longer usable for my purposes. At 30K miles, I might be ready to replace the whole bike!
If I only charge to 80%, then it will lengthen the life of the battery. But I won't get the kind of performance this bike is capable of. It's not just how far you can go on a charge, but how much pep the bike has at a given state of charge. On my battery, the first 75% is pretty much the same thing: good acceleration, etc. After that, it is still good, but I start to notice a drop-off. Takes longer to get up to speed, takes more pedaling to maintain a given speed at a given level of pedal assist, and so on. If I only charge the battery to 80% to begin with, then I only get that kind of performance from 80% to 75%, instead of 100-75%. If that is acceptable to some, or the thought of having to swap out an expensive battery a couple of years sooner is not in the budget, then the 20-80 deal makes perfect sense. Not for me. I like the performance of the CCS and want to enjoy it when I ride. Even though I ride most of the time in Eco and 1, as mentioned above.
With the new 52V, 21Ah batteries, this may not be an issue. I look forward to getting one in the not too distant future. At that point, I'll recalculate whether the 20-80 regimen works for me.
Oh, BTW, when I say 100%, what I mean is putting it on the charger, and then taking it off when the light turns green. On the stock 2 amp charger, this is really more like 95% instead of 100%, gauging by voltage. On the charts I've seen, going to 95% instead of 100 gives the average battery about 100 more cycles. So really: this is a non-issue for me.
If we're all still around a couple of years from now, it will be interesting to compare how our batteries are doing.
Bruce Arnold
Well-Known Member
Chris, don't get another Satiator for work. Get a cheap-ass 52V charger like this one. You're just dropping some juice in for the ride home.
Here's another question: I will be storing my 19.2 battery for 5 months, every year for the foreseeable future. I read about 50% charge being optimal for storage. I don't have a Satiator. Originally, I figured to bring the battery with me to winter in Florida. But I am not bringing the bike, just the battery and the basic charger. But then I thought, maybe it would be better to leave the battery in my Upstate NY basement-at a pretty constant Temperature of 55 degrees. If it goes to Florida, it will be travelling for 3000 total miles in the back of my van, and when I get there, be stored at about 75 degrees average. I read that these lithium batteries may lose "3-5%" charge per month. If I left the battery charged to about just over 80% (52v), it should be above 40v when I get back. Or would this be cutting it too close/ too low for comfort? Appreciate any thoughts...
Bruce Arnold
Well-Known Member
That 55 degree temp is pretty much optimal for lithium ion battery storage. Not that you'd hurt it by taking it to Florida. If you leave it at around 50% charge, it should be fine for about 6 months without additional charging.
Fran Fabrizio
Member
For what it's worth, I'm using the Luna charger just fine. Luna sells an XT60-to-barrel adapter, and then you just use the barrel-to-XLR adapter that came with your bike from Juiced.
Fran Fabrizio
Member
I do effectively this same commute with the 48V 17.4Ah battery doing 80/20 and using level 2 most of the time, and I end the day with battery to spare above 20%. I doubt you'll have any issues whatsoever unless you ride super aggressively.
I agree, however the bike is a lot peppier above 50% charge so you might want to top it off a bit at work. Definitely not necessary to make that trip though. When I did 30 miles on my CC with my 17.4Ah battery on S mode it was getting sluggish towards the last 25% of the ride.
Jeffrios
Member
I wasn't planning on bringing the charger to work with me. I an going to make my first test ride hopefully this weekend starting at 100% and see how much energy I use and then do some calculations.
