How many cycles from Hobby King lipo?

Wondering how many cycles others are getting from their hobby king lipo batteries?

I'm expecting upwards of 1K, but will be happy with 300 full cycles. Wiki says lipo is good for 500-1000 cycles. Think I saw someone here that's been using them since 2008 say they had over 600 cycles on theirs.

I'm hoping for at least 300 cycles myself too. That'll be a year's worth of use for about $300 worth of batteries in my case. Is it wise to go and buy another set of replacement lipos? I thought I read somewhere they have a finite shelf life regardless of them being used or not?

Many of my HK RC bricks have been in use over a year - while I don't log each charge cycle I have a very consistent pattern of weekly use. My oldest bricks have at least 300 cycles and they do not exhibit loss of capacity - only very small increase voltage sag used powering 20-35A loads.

Key to longevity is not fill 'em up beyond 4.15V/cell - less if you don't need max capacity. MilSpecs stipulates 3.96V/cell for this chemistry and they probably have a good reason. Also 'never allow any cell to drop below 3.5V/cell resting potential. In order to maintain these numbers top/bottom cell balance is extremely critical parameter. But good news is that healthy cells remain in excellent balance - much better than LifePO4 packs I've had experience with.

If you can buy and carry more than you need to keep the depth of discharge low, adhere to not charging more than 4.15v, you will extend the life of the batteries well beyond what they are rated for. I currently carry 12s3p and rarely go beyond 50% Discharge which means to get 1 full cycle I have to discharge to 50% twice and I don't always get to 50% discharged.

Between these two strategies I'm pretty sure my battery pack is going to last many many years and the whole thing with trunk case weighs 13 lbs. Lipo is the best solution for mobile vehicles if you are comfortable with it. I had zero experience with it until a few months ago, but it seems safer to me than the highly volatile fuel we all use in our cars known as gasoline which causes many fires every single day.

I've had mine since 2008. no idea on the cycle count but over 5000 miles on them.
They still hold 80%, but are becoming tricky to keep balanced.

I always charge to 4.2V, but I rarely take them below 3.7V

I think Age is the big killer at this point, not cycle life. But 3 years is a good long life for Lipo. they might even make 4 years.

Depends wildly on the quality of the LiPo you bought, and how they are used.

Easily capable of thousands of shallow cycles.

Dead in a hundred or less extremely severe cycles.

Looking through the wide ranges of choices in hk lipo I'm a bit confused. 15c, 20c, 25c, 30c, 35c, 40c, zippy, turnigy. What's the difference? I understand that some of them come from the same batches, but the lesser quality cells are sold as lower C rate. Like the 15c packs are the same chemistry as 30c, but didn't pass muster and are down rated. Most tellingly you can see this with the nano-techs, since hey offer 25c versions of them.

Am I wrong? Am I right? Does anyone even know what packs are from what chemistry groups/batches? I wouldn't want to buy 30c packs if they were sub-par 35c packs. Better off with the 25c if that was the case.

auraslip said:

Looking through the wide ranges of choices in hk lipo I'm a bit confused. 15c, 20c, 25c, 30c, 35c, 40c, zippy, turnigy. What's the difference? I understand that some of them come from the same batches, but the lesser quality cells are sold as lower C rate. Like the 15c packs are the same chemistry as 30c, but didn't pass muster and are down rated. Most tellingly you can see this with the nano-techs, since hey offer 25c versions of them.

Am I wrong? Am I right? Does anyone even know what packs are from what chemistry groups/batches? I wouldn't want to buy 30c packs if they were sub-par 35c packs. Better off with the 25c if that was the case.

Click to expand...

Yup, it's easy to get confused. lots of options.

I don't know about this 'dud cell theory'
You know why? because the lower C cells weigh less, and are physically smaller in size.

Compare a zippy 15C pack to a zippy 30C pack..

If you are picking batteries for your bike, you need to look at your amp draw first in order to decide.
Realistically, i can run run 40-43 amps constant ( 7-8C or so ) on my 20C 5AH Turnigys and they barely get warm, and i get a 1.5 volt dip. If i run 10AH i get ~.75v of dive and they don't even get over ambient temp..

Nanotech is obviously the best, but if you are running 10AH and under 50 amps, then 15C zippys will work fine. Running these batteries at 1/3rd of their rated C is babying them.. lol.

auraslip said:

Looking through the wide ranges of choices in hk lipo I'm a bit confused. 15c, 20c, 25c, 30c, 35c, 40c, zippy, turnigy. What's the difference? I understand that some of them come from the same batches, but the lesser quality cells are sold as lower C rate. Like the 15c packs are the same chemistry as 30c, but didn't pass muster and are down rated. Most tellingly you can see this with the nano-techs, since hey offer 25c versions of them.

Am I wrong? Am I right? Does anyone even know what packs are from what chemistry groups/batches? I wouldn't want to buy 30c packs if they were sub-par 35c packs. Better off with the 25c if that was the case.

Click to expand...

2 factors determine the C-rate.

The combo of powders used in making the slurry, and the foil thickness and surface finish.

Cells get a formation charge and cycle test. If they measure up inside the top-bin tolerance, they generally go into OEM modules/packs. If they have abnormalities that effect function, like excessive Ri, self-discharge/shorts, drastic over/under capacity, they are recycled. If they have just a mild deviation, they go into RC packs. If they have more than mild deviations, but no critical flaws, they go into the deep discount packs, b-stock, ebay, etc.

Nothing makes a 30c pack into a 20c pack or whatever, that is determined by the foils and powders used, and if one really had something like 50% higher Ri, it would be recycled, as it indicates something critically went wrong inside the cell to have that amount of deviation.

Recovering an old thread to share my experience:

This week, and after 2 years since purchase, started to show a drastic sag when used below 3.80v per cell.

Now HOC (4.20v per cell) won't reach max speed(40mph). And below 3.80v per cell won't reach 18mph

I made 400 to 450 cycles, using usually 1/2 of a 15s 4000mah turnigy 30C battery (short commute). Controller is modded to extract 50A aprox.

When discharged and measuring independent cell voltages, cells where aprox in the same voltage (+/- 0.04v), so no weak individual cell.

C rate depends not only on the things lfp mentioned but on the porosity of the separating membrane and the ratio of interconnect to electrode.

Cells are designed around a given discharge rate. Different discharge rates need different designs. As a general rule, the higher the discharge rate the lower the energy density. They don't just bin cells as different C rates, since if something gets screwed up it will usually be capacity or a soft short or something that renders the cells unusable. Cell quality tends to be pretty uniform with a smooth running process.

Sounds like you treated your batteries well but they just didn't live as long as expected. This happens with HK batteries. Test capacity if you can since it's probably way down and internal resistance is up. You might be able to keep the packs for extra range with additional new packs that can provide the discharge you need. But I wouldn't push them alone since they're most likely building up heat faster.

My experience with HK Lipo has been pretty good. 90% of the time I only charge to 4.1v and never hit my low voltage alarm set at 3.6. I treat them well. My worst packs were multistar 6s 8amp. I have 4 packs and 2 have a puffed cell I luckily found when checking balance a couple days after charging. They are all 13 months old with about 100 cycles. On a positive note they didn't catch fire when I tried to explode them I have Zippy's and Turnigy's that are 2-5 years old that still work great.
My oldest and favorite are the Hyperion brand. Some are 8 years old and still have over half capacity. I have a batch from 2011 that work like new despite being charged at the max rated 5c! But they are costly.

They can last long, but with degradation. If they are rated true numbers, you can expect 150 perfect complete cycles. This means charging and discharging as fast as they are rated, never above 4.2v and never lower than 3.7v. After those 150 first cycles, they will degrade progressively and suffer up to 20% capacity loss at 300 cycles.

Be harder on them, and they start to degrade earlier, faster. Be easy on them, and they start to degrade later, slower.

There are many ways to be hard on them, with more or less consequences. Like overcharging just before a ride is not as hard as overdischarging at the end of the ride. Forcing higher discharge than C rate is very hard, while forcing charge rate is not that bad if you don't let them become hot. Using them at the cold limit of their temp range rating is not as hard as letting them heat above their high rating.

Then, you can presume that rating numbers are not always true, and that some cells are not as good as the others in a pack.