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Old 03-07-2012, 06:26 AM   #16
vtbob
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Joel

It is valuable that you are doing this testing. While I think Lithium technology batteries have great promise, I also think some of those marketing them have been less than honest in spinning and miss using technical terms to hide some current weakness.

I look forward to your test to set the record straight
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Old 03-07-2012, 08:30 AM   #17
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Originally Posted by JoelWisman View Post
You have to upload them from your computer to a photo sharing sight first. Many are free. Then click share on the picture you uploaded, copy the HTML code it spits out, and paste it here.

Simple once you try it 15 different ways and find one that works :)
too bad....i don't use those sites...i guess i will not be able to share the pics of the the batteries...
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Old 03-14-2012, 02:10 PM   #18
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Quote:
Originally Posted by JoelWisman View Post
How well and quickly do these batteries accept charge? The scooter is regulated at 14.1 volts, the Capo at 14.55, I think (will test), the R12GS at 14.4 volts, the F800GS at 14 volts at idle and 13.8 at speed (freaky and wrong, but it's what they do so lets test it)

Joel,

I have a 2011 F8 (built Nov 2010) and my voltage while the bike is running is 14.4 nearly all the time. During idle, at all engine speeds, etc.

With no extra loads, it fluctuates between 14.4 and 14.5, and with the heated grips on high it's 14.3 and 14.4.

Not saying you are wrong, but perhaps something changed?
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Old 03-14-2012, 03:20 PM   #19
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Originally Posted by NCD View Post
Joel,

I have a 2011 F8 (built Nov 2010) and my voltage while the bike is running is 14.4 nearly all the time. During idle, at all engine speeds, etc.

With no extra loads, it fluctuates between 14.4 and 14.5, and with the heated grips on high it's 14.3 and 14.4.

Not saying you are wrong, but perhaps something changed?
I just had a friend stop by yesterday with a 2012 F800GS and captured it's charging using both a scope and recently calibrated meter in min/max mode.

Are you testing at the battery? Real sure of your test equipment accuracy? Is there a purple dot on the back of your voltage regulator?

Heres what I am seeing, and I just checked the Fluke 867B against my newly calibrater 289, spot on.



I wasn't actually working the regulation issue but rather the Stator toast issue, so didn't record above idle on video, but did rev it and see it, dropped to high 13.8's when the engine rpm was raised.
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Old 03-15-2012, 07:57 AM   #20
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It's a Battery Bug straight to the battery. No purple dot on the back of the RR. There is a molded in capital A with a small white paint dot in it, and the markings SH541SC 0.0061 on the back.

Others have reported findings like yours (13.8 running) with the Battery Bug. After riding last night, my standing voltage is displayed as 12.8 this morning. (Which I assume is normal, right?)

Hmmm.

And if I'm mucking up your thread, tell me to get out!

NCD screwed with this post 03-15-2012 at 08:13 AM
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Old 03-15-2012, 01:44 PM   #21
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Cool2 Shorai working well

I've had a Shorai in my GS8 since August and bounced it around good on some very rough roads on my fall tour. So far, so good. I ride nearly every day and depend on the bike to do the charging for me. So far, so good.

I hope that's my answer a couple years from now, too.
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Old 03-16-2012, 02:01 AM   #22
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Originally Posted by NCD View Post
It's a Battery Bug straight to the battery. No purple dot on the back of the RR. There is a molded in capital A with a small white paint dot in it, and the markings SH541SC 0.0061 on the back.

Others have reported findings like yours (13.8 running) with the Battery Bug. After riding last night, my standing voltage is displayed as 12.8 this morning. (Which I assume is normal, right?)

Hmmm.

And if I'm mucking up your thread, tell me to get out!
No, NEVER! I appreciate all reasoned input, do stay.

12.7-12.84 volts is 100% state of charge for lead acid batteries, the range owing to various chemistries. So your resting voltage is spot on assuming you still have an AGM battery in your bike.

That said, a good precision resistor, capacitor network, what is used to make precision voltage measurements inside multimeters and such costs manufactures $40 bucks and up. Any product that costs less then about 120 bucks does not measure voltage this way and it's readings have to be taken with a grain of salt.

It may be that your battery bug is not linear and is optimistic about the charging voltage which I wouldn't fault it for, especially since I like that product.

It also may be that your bike does not have the standard regulator in it.

Something that is normally kept secret from the public........ Manufactures including BMW make small scale substitutions all the time without informing anyone including their dealer network.

It is entirely possible that they have installed a different voltage regulator on a few dozen bikes to see if it makes the battery last longer, catches on fire, inter fears with the ABS and makes the rider crash LOL.

Mostly kidding about the last, but in any case, they conduct secret trials and usually they make the replacement item look as similar as possible down to the part number. They track results without even their dealers knowing by following the bikes VIN through warranty history.

A purple dot used to be their secret identification code, but may and should have abandoned the dot as it wasn't very secret lol.

The stator longevity issue has been determined. It can be fixed by reengineering some resistance into the voltage regulator as well as driving up the shunt voltage. Changing the stator harness for one with higher resistance or making something to add resistance between the stator and regulator harness, or changing the oiling or completely reengineering of the stator / flywheel.

Doing it at the voltage regulator would be desecrate and cheap and could kill another bird with one stone, so they MAY be running trials and you MAY have gotten a test unit.

I will post on the stators in another thread for clarity, soon.

I will post more about batteries here soon. completed all the first rounds of tests, compiling data, pictures, and video.
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Old 03-16-2012, 06:08 AM   #23
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Originally Posted by JoelWisman View Post
.... The stator longevity issue has been determined. It can be fixed by reengineering some resistance into the voltage regulator as well as driving up the shunt voltage. Changing the stator harness for one with higher resistance or making something to add resistance between the stator and regulator harness, or changing the oiling or completely reengineering of the stator / flywheel...


I'll be watching the "Another alternator bites the dust and not under warranty" thead?
here? http://www.advrider.com/forums/showthread.php?t=706033
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Old 03-16-2012, 07:46 AM   #24
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Executive summary of imbalance in Lost Riders Shorai LFX18

Battery arrives and I measure a huge imbalance between cells.

This is important for a couple of reasons. One, a series battery only has as much capacity as its weakest cell. Two, batteries that are charged in series see stresses on cells when imbalances occur and lithium batteries are particularly susceptible to damage from imbalance stress.

Lead acid batteries will balance them selves when charged to modest voltages, at the least, the Shorai LFX18 chemistry will NOT.

The F800GS and F650 GS stand out amount BMWs entire line-up as having good charging system capacity but low charging voltage.

This battery was about to fail from critical imbalance, and likely without any warning. No warning because unlike lead acid, LiFePo4 batteries usually work great till they don't.

I first put the battery in my Caponord and rode around after installing a BMW F800GS voltage regulator so it would charge just as if it was in an F8. The battery charged up some more compared to when I got it, but no balancing occurred.

I then put the Capo's much hotter voltage regulator in, and rode for a while and a measurable improvement in balance occurred.

I then "bottom balanced" the batteries until all cells were perfectly balanced, used the battery hard for other tests, and when finished, the battery was once again drifting out of balance.

Hypothesis: The F800GS and F650 GS have too low of voltage regulation for Shorai batteries. This would explain the stories on ADV and a half dozen PM's I have gotten since I started this thread of "sudden shorai battery failure on F8s. It would also explain why Shorai keeps raising the recommended battery size for the F8.

There are other possibilities I can't rule out, yet. Perhaps this battery was defective and doomed to failure from the start. It's a chicken or egg thing. did the imbalance damage the battery, as I suspect? Or did a defect cause the battery to imbalance? Did the owner damage it?

Also, perhaps chemistry is slightly different on other Shorai models, and it is surely different with other brands. Perhaps another model or brand will work? Next post, highly technical details of how I arrived at these findings in black text. Dont read it unless you have time to kill and like the little details :)
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Old 03-16-2012, 08:18 AM   #25
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Quote:
Originally Posted by JoelWisman View Post
Executive summary of imbalance in Lost Riders Shorai LFX18

Battery arrives and I measure a huge imbalance between cells.

This is important for a couple of reasons. One, a series battery only has as much capacity as its weakest cell. Two, batteries that are charged in series see stresses on cells when imbalances occur and lithium batteries are particularly susceptible to damage from imbalance stress.

Lead acid batteries will balance them selves when charged to modest voltages, at the least, the Shorai LFX18 chemistry will NOT.

The F800GS and F650 GS stand out amount BMWs entire line-up as having good charging system capacity but low charging voltage.

This battery was about to fail from critical imbalance, and likely without any warning. No warning because unlike lead acid, LiFePo4 batteries usually work great till they don't.

I first put the battery in my Caponord and rode around after installing a BMW F800GS voltage regulator so it would charge just as if it was in an F8. The battery charged up some more compared to when I got it, but no balancing occurred.

I then put the Capo's much hotter voltage regulator in, and rode for a while and a measurable improvement in balance occurred.

I then "bottom balanced" the batteries until all cells were perfectly balanced, used the battery hard for other tests, and when finished, the battery was once again drifting out of balance.

Hypothesis: The F800GS and F650 GS have too low of voltage regulation for Shorai batteries. This would explain the stories on ADV and a half dozen PM's I have gotten since I started this thread of "sudden shorai battery failure on F8s. It would also explain why Shorai keeps raising the recommended battery size for the F8.

There are other possibilities I can't rule out, yet. Perhaps this battery was defective and doomed to failure from the start. It's a chicken or egg thing. did the imbalance damage the battery, as I suspect? Or did a defect cause the battery to imbalance? Did the owner damage it?

Also, perhaps chemistry is slightly different on other Shorai models, and it is surely different with other brands. Perhaps another model or brand will work? Next post, highly technical details of how I arrived at these findings in black text. Dont read it unless you have time to kill and like the little details :)




Erling
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Old 03-16-2012, 09:01 AM   #26
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In post 5, I posted some very large cell imbalances in the used Shorai LFX18 battery sent to me by Lost Rider. The post above was the summary, heres the technical details.....

As the battery arrived

at least 4 days of resting13.149
cell1 3.2965 70%
cell2 3.2962 70%
cell3 3.2938 70%
cell4 3.2633 35%
35% imbalance

Capo w F8 regulator 4.5 hours 3 starts 125a withdrawn for 10 seconds, rest 1 hour
cell1 3.2998 70%
cell2 3.2995 70%
cell3 3.2970 70%
cell4 3.2657 35%
Notice the imbalance is the same, so riding around with this battery in an F8 or F650 twin with stock regulator is not going to fix this issue and likely allow it to get worse.


Withdrew current from cells individually at approx 0.2 amps to 3.2165 volts (would be 12.886 volts for battery or 20% SOC) This is a 30 hour rate. Shorai says some BS about “PBEQ amp hour” as do all the LiFePo4 power sports battery manufactures I can find. Dig and you find out the LFX18 battery is 6 ACTUAL amp hour, but state that using the bottom 20% will damage the cells and void your warranty. This means you effectively have a battery that is 4.8 amp hour
cell1 2.56 amps 53%
cell2 2.99 amps 62%
cell3 2.87 amps 60%
cell4 0.81 amps 17%
This was a pain in the ass to determine! My budget is a shoestring and package of Ramen noodles, the cheap brand, so grabbed some resistors, capacitor, comparator potentiometer and a logic chip, oh yeah, and scavenged a transistor from a broken electrical gadget I had at the house and built my own bottom balancer :) With a bottom balancer, you set a voltage and the balancer sucks current till the voltage you have set is reached. Repeated for each cell, and amp hours above was what was measured. Cell 4 only hod 0.81 amp hours! Battery is in series, so it's total capacity was 0.81 amp hour!

You can go below this, as this is leaving 20% in reserve so as not to invalidate Shorai warranty, or damage battery, but this was one sick battery!


charged cells individually same amount as withdrawn, per cell + 10% for a guestimate at charge eff. I had to do this manually which was really boring! But, I started watching the walking dead on netflix while glancing down at the readings on the meter every 30 seconds and now I'm hooked!

After 26 hour rest
cell1 3.2991 70%
cell2 3.2997 70%
cell3 3.2968 70%
cell4 3.2646 35%
close enough for government work


Installed the battery in the same imbalanced state into the Capo. rode 6.5 hours 7 starts, over 2 days
1 hour after 125 amps for 10 seconds
13.708 volts
cell1 3.5820 100%
cell2 3.4448 90%
cell3 3.3447 90%
cell4 3.3142 75%
OOOO!!! 25% imbalance
The F8 has a lameish 13.8 volt charging voltage, as confirmed on many previous bikes, as confirmed on my Capo with F8 regulator installed. For the test above, I put the Capos regulator back in which tends to charge in the 14.35 to 14.55 region.
10% of the imbalance went away after just 6.5 hours of riding!


3 more hours of Capo riding, all freeway
cell1 3.5819 100% (rounded up ever so slightly)
cell2 3.4494 90%
cell3 3.3492 90%
cell4 3.3181 80%
now we are down 5 more % to a 20% imbalance. Im convinced. The F8s voltage regulator is set too low for at least that particular battery and likely all Shorai batteries though I don't know the latter for sure, yet.

To test it one other way, look at this:
Deka ETX14 with an absolutely constant 13.828 volts applied. 1 full day later the battery was still drawing 68.7mA. This is because, lead acid batteries as a rule can be charged at well over their nominal voltage without harm. Normal OCV 100% SOC 1s 12.8 volts, but you charge them at far higher voltages. In any case, even at 13.8 constant volts, a small current will continue to flow. The fully charged cells gas slightly. it doesn't harm them because the battery is sealed and the gasses recombine, but this small trifle of current at moderate voltages allows juice to get past the full cell (s) and charge any low cells naturally balancing all of the cells. Imbalance is virtually NEVER a problem with lead acid batteries with the one exception of Optima spiral cell batteries.
DSC_0316

Now look at Lost Riders Shorai LFX18 battery. Same constant voltage for a full day. 0.2mA of current flow. The battery is imbalanced, cell 4 is begging for more charge, but at 13.8 volts, the full cells have stopped current! This is one part LiFePo4 behavior and one part 13.8 volts is not even 100% SOC OCV. Ok, a little current is flowing, but tiny tiny. It would take about 87 years for this battery to naturally series balance at this current flow rate, and more like never because the cells internal discharge rate is likely near here. This is such a low voltage that if you took the probes of a multimeter flowing this current and stabbed them into your brain, you wouldn't feel it! Well, you would feel that you had stuffed stainless steel probes into your brain, but it wouldn't even make a muscle jump! Ehh, actually some muscles would jump, but not from this tiny current which is smaller then what nerves send to muscles, you would have muscles jump because you are stabbing your brain with stainless steel probes! Either way, I wouldn't advise it, but you get the idea. For at least this battery, and possibly all Shorai batteries, 13.8 volt charging systems are too low and are likely the cause of the sudden failures I keep hearing about.
DSC_0323


Here is a bad graphic. I am bad at graphics using good software. This was hammered out on Pages, a word processor. I leave it to you to try to determine what I am illustrating.

Untitled

Ok, I have actually completed warm cranking testson both the LFX18 and a Deka ETX14 lead acid for comparison and did reserve tests as well as static load tests, but I am tired of typing so am going to go for a ride in a thunder storm, more later + some general Lithium / lead/acid stuff.
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Old 03-16-2012, 09:34 AM   #27
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Quote:
Originally Posted by JoelWisman View Post

...
Lead acid batteries will balance them selves when charged to modest voltages, at the least, the Shorai LFX18 chemistry will NOT.
...
Let me see if understood...

F800GS Alternator and voltage regulator have been designed to work with nothing but with AGM battery's?



A local dealer (who's also an ADV member) as been experimenting with a ballistic in his HP2 and so far had no problems whatsoever, and they have the same chemistry as Shorai right?. So i can't expect the same result due to our shitty voltage regulator?



P.S. Thanks Joel for taking the time to educate morons like me on such a great thread, as it has been from almost every post I've read from you since i joined ADV, although i don't write much, i have a great appreciation for your threads, and hope you find a job soon, that would help me a lot on keeping mine as i would spent a lot less time on your threads.

Cheers
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Old 03-16-2012, 10:58 AM   #28
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Quote:
Originally Posted by skamikazee View Post
Let me see if understood...

F800GS Alternator and voltage regulator have been designed to work with nothing but with AGM battery's?



A local dealer (who's also an ADV member) as been experimenting with a ballistic in his HP2 and so far had no problems whatsoever, and they have the same chemistry as Shorai right?. So i can't expect the same result due to our shitty voltage regulator?



P.S. Thanks Joel for taking the time to educate morons like me on such a great thread, as it has been from almost every post I've read from you since i joined ADV, although i don't write much, i have a great appreciation for your threads, and hope you find a job soon, that would help me a lot on keeping mine as i would spent a lot less time on your threads.

Cheers
My apologies from distracting you from riding LOL, that truly did make me laugh out loud forcefully

As to BMW design, it's just the F8 and F650 twin, HP2 has a great charging system as do all the other current bikes.

As far as I can tell, BMW designed the charging system to work with a GEL battery which requires a low maximum voltage, then shipped the bike with an AGM that does not appreciate the low voltage much more then a Shorai, though it works longer ONLY because lead/acid batteries don't have issues with charge imbalance.

As to Balistic, Antigravity, or other brands, they likely all have differences so I can't draw any conclusions about them without testing one of them. It is also possible that this battery was defective from the get go or damaged in use, as well as possible that other Shorai models or possibly more recent batteries made by Shorai are different.

All of the power sports lithium batteries are LiFePo4 base chemistries, but they all have more subtle differences.
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Old 03-19-2012, 02:29 PM   #29
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Okay, So, we now know that the Shorai chemistry, at the least, won't hold balance when used ONLY with a charging system that maxes out around 13.8 volts.

We know this for certain because I just finished testing a brand new Shorai LFX18. I Un-balanced it deliberately by withdrawing 1 AH from a single cell through the BMS receptacle, then charging it to a voltage limited 13.8 volts.

Same outcome as Lost riders battery. Less them 1 mA flowed past the full cells into the heavily depleted cell indicating that no natural series balancing is going to occur at this voltage in our lifetimes :)

Next up, I applied 14.4 volts which is a typical charging voltage for most bikes in the world that are designed to run with AGM batteries. Hello mama! 17 mA flowed continuously.

Okay, that would take about 58 hours of riding to rebalance the amp hour I took out, but at that flow rate, it's likely the imbalance would never occur in the first place.

So, how big of an issue is this for K7 owners? Hard to say for certain. I have no doubt that Lost riders battery is damaged, either through defect or Lost riders usage pattern. The new Shorai LFX18 showed no imbalance but it is ALWAYS going to occur eventually if the charging voltage is not high enough to naturally correct it, but might take years to be significant or may be a lot faster. I don't have the time or will to find out.

If anyone else wants to test for this, use a multimeter with at least 4 digits and record between the following pins on the BMS receptacle: 1 to 2, cell 1. 2 to 3. cell 2. 3 and 4, cell 3. and 4 to 5, cell 4. Use the SOC chart above. any readings that indicate more then a 10% imbalance would be considered extreme. More then 20% and your battery is getting stressed with each use and is likely to fail suddenly and soon.


How can we avoid this all together and still use a LiFePo4 battery?

First, the doping off all the major cell manufactures is going to be different, so this issue may not occur with other brands.

I have an AntiGravity battery on it's way to me and will be testing for the same in it. Ballistic is anyones guess. If anyone happens by that has one of those, I will test it the same.

Next, even with a Shorai installed in an F8 with stock voltage regulator, occasional charges with a balancing charger like this one will prevent imbalance from ever getting bad. Probably once a month would be fine.

Last, you can change the regulator on the F800. A shunt regulator is a shunt regulator. Find one online or at a scrap yard that is rated for at least 400 watts and all is good. Of course you want one with a charging voltage higher then 13.8 volts, ideally 14.2 to 14.4, but honestly, the k7 platform is the only I can think of that charges at such low voltage so odds are every other regulator on the market will have a reasonable voltage setting that will operate fine with AGM and LiFePo4 batteries.

So, problem found, easily rectified, but something to think about if your wanting to or have already moved to LiFePo4 batteries.

This problem is ONLY going to occur on K7 bikes, AKA F650GS twin, F800GS,S,ST and R. This will NOT be an issue with any other current BMW bikes.

P.S. simple language for what this problem means. A battery is just like old christmas tree lights where if even one bulb went, the whole string stopped lighting. This is so for both lead/acid and LiFePo4 batteries. So when even just one cell falls out of balance and stops completely charging, it reduces the capacity of the whole by that same amount. If cell 2 is undercharged by 30% while all the other cells are full, the whole battery will act dead as soon as 70% of the capacity is used.

Next, the cells in the pack are wired in series which each, when balanced, dropping the same voltage while charging. When a single cell is undercharged through imbalance, that cell drops less voltage and the remaining 3 see over-voltage, overcharging and getting destroyed over time.


Alright, done with that issue, for now. Will report on if it is also an issue with Antigravity batteries once I have one for testing.


Next up, head to head trials between the Shorai LFX18 and a Deka ETX14 battery. Results in, video taken, just have to write it, but for that, I'm going to ride my big ass adventure bike to Starbucks more in a little bit,
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Old 03-19-2012, 02:41 PM   #30
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Originally Posted by JoelWisman View Post
Next, even with a Shorai installed in an F8 with stock voltage regulator, occasional charges with a balancing charger like this one will prevent imbalance from ever getting bad. Probably once a month would be fine.
There are two main reasons for me to use a lithium battery: 1) maintenance free and 2) kill some weight. Number 1 is a bigger deal to me than number 2. If the conclusion is that the battery is very far from maintenance free, suddenly half or more of my motivation for running with a lithium battery is gone. Just a personal reflection.
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