Motorcycle Batteries .. AGM, GEL, Wet, Lithium Iron Phosphate (LiFePO4)

cy-

To clarify to the real amp hours could you put up an overvievv vvith the different batteries.

ETX18, ETX21, ETX24....ETX36 etc

Shorai 18, 21, 24,....

And i don´t care vvhat any vendors claims. Just your honest results based on your test.

As i read it ETX36 should be 36ah but in real life its 10.79ah?

Regards
Mikael

there's plenty of detailed data concerning actual amp hours measured posted a few pages back. don't worry it won't put you to sleep too bad digging

something simple sounding like amp hour capacity can become complex quickly. for example at what temps and discharge rates did mfg do measurements at?

discharge and charge rates are expressed in terms of 1C or .1C or .5C , where C = actual AH

lithium (li-ion) batteries in general has very low internal resistance characteristics. discharge rate effects total efficiency achieved. which will be different yet depending on temps. at -10C LifePO4 AH capacity drops by aprox 50%

for example discharge measurement done at .1C will yield slightly higher AH measurement vs .5C vs 1C vs 28C .. etc.
this is why how bike will be used makes a huge difference.

Joel W did an excellent series of tests videos with Shorai LFX 18 that drove in this home.

below LFX 18 was subjected to brutal stress test of leaving 2x 55 watt headlights (10.9amp drain) on for five minutes, then cranked bike over to start. LFX 18 survived brutal 10.9amp drain for 25 minutes, then starting bike 6x times at 5 minute intervals. LFX 18 finally failed at 28 minutes subjected to 10.9 amp drain.

an amazing performance from LFX18 under light load conditions... yet LFX 18 failed 10 seconds into a 200amp stress test in second video below

<iframe src="http://www.youtube.com/embed/-nm7bl39uxk?feature=player_detailpage" allowfullscreen="" frameborder="0" height="360" width="640"></iframe>

Joel also did a series of 200 amp continuous discharge tests for 30 seconds, 10 sec, 20sec = one cycle. LFX 18 didn't even make it pass one cycle of 200amp discharge testing. yet LFX 18 managed to start a modern motorcycle multiple times with headlight left on for extended periods.

this test illustrates how a properly size AGM battery performs next to a LiFePO4 battery sized way too small.

<iframe src="http://www.youtube.com/embed/ySNbSZTgplA?feature=player_detailpage" allowfullscreen="" frameborder="0" height="360" width="640"></iframe>

Hi,
I am reading your LiFePo4 thread presently. Good stuff here. I've seen you on Candlepower forums as well.

I have a Battery Charger question.

I have a PC925 in my Beemer.

I just put an Odyssey 31m-pc2150 in my Landcruiser. Big MoFo!

I'm looking for a good 40-50 Amp charger that will do AGM batteries well. It is confusing and I can't seem to find a good site addressing car chargers well. I was thinking of building a PL-8 system like you have in the past. I had actually purchased 2 HP Server power supplies to put in Parallel for this but now am just looking for a decent, not too expensive charger to do these AGM's in my bike and cars.

Do you have any ideas on a decent charger? I was looking at a Schumacher PSC-12500A DSR but don't know if I should be looking elsewhere. The Ultima Chargers by Odyssey are expensive and look like a Schumacher to me.

Thanx!
Les

what an excellent question!

AGM batteries are still the preferred choice for most adventure motorcycles. with the exception of Shorai LFX 36 and Earth-X ETX36 when saving weight is more important than saving $$$.

it's important not to overcharge ... AGM cells like to be charged at [FONT=Arial, Helvetica, sans-serif]2.40V to 2.45V/cell = 14.4v to 14.7v for max [/FONT]capacity with less sulfation. [FONT=Arial, Helvetica, sans-serif]2.30V to 2.35V/cell = 13.8v to 14.1v for max service life [/FONT]

AGM batteries that's gone thru a severe discharge. a reconditioning charge cycle may be in order. but that takes a charger with a conditioning cycle and/or a constant voltage charger that delivers 15.5v

AGM 12v batteries charges very close to flooded PB batteries. main difference you can hurt AGM by overcharging easier vs flooded PB.

there's three stages charging an AGM battery..

1. bulk charge stage .. this where battery will absorb all the amps charger will deliver. batteries depending on chemistries like to be charged at 1C to .5C rates. For a typical 12 volt AGM battery, charging voltage going into a battery will reach 14.6-14.8 volts, while flooded batteries can be even higher. For gel battery, voltage should be no more than 14.2-14.3 volts.

2. Absorption charge phase .... Once the battery has reached about 80% state of charge, charger will enter the absorption stage. At this point most chargers will maintain a steady voltage, while amps declines. The lower current going into the battery safely brings up the charge to full.

This stage takes more time. For instance, the last remaining 20% of the battery takes much longer when compared to the first 20% during the bulk stage. The current continuously declines until the battery almost reaches full.

3. Float stage .. Some chargers enter float mode as early as 85% state of charge but others begin closer to 95%. Either way, the float stage brings battery all the way to full and maintains 100% state of charge. The voltage will taper down and maintain at a steady 13.2-13.4 volts, which is maximum voltage a battery will hold. The current decreases to a point where it's considered a trickle.

some trickle chargers never stop charging, eventually overcharging battery vs an intelligent trickle charger knows when to stop all current without turning off. those chargers are completely safe to leave a battery in float mode for months to even years at a time.

my preferred charger for AGM motorcycle batteries is a Schauer 6 amp automotive charger, the non-intelligent type. also have a 15 amp Schauer and 60 amp Snap-on for truck size auto AGM & flooded PB batteries.

note Schauer non-intelligent chargers, once it reaches full charge will not terminate current. but will deliver a small trickle charge long as charger is plugged in. this means you need to unplug charger after charging overnight. just don't leave charger over 48 hours in trickle mode.

advantage of dumb chargers .. they just work... no wrong measurement of internal resistance by intelligent chargers to prevent charging certain type batteries. like motorcycle size AGM batteries.



this Schauer 25amp intelligent charger works good for auto sized AGM, but sucks for motorcycle size AGM. switches to float mode way too soon.






this odd-ball charger made in 60's .. charges at 15.3v or perfect for reconditioning a badly discharged AGM.

CY...

Thanks for your reply, and info... Now that got me thinking, so thought id share some thoughts, see if you have any answers...

04 R1100S, 10k miles, Original BMW Battery, 19mah gel i think, with a don't sell date of end 07, bike sold new end of 07...

Our summer temps 80f to 90f, winter down around the 30f, summer now, and while riding around town the other day, stop start at many lights, i decided to kill the motor at lights using the kill switch, which means the lights on, indicator on, ignition still live, when the lights go green hit the starter and go...

So the thinking is not to sit idling for ages, getting the motor temps up, but obviously putting more stress on the battery and starter...

How much juice is being used doing that, and would a Shorai handle that...

The listed Shorai battery for my bike is LFX21L6-BS12

I use Lipo, and Life batteries in model planes, and have the charging gear with balancers...
Keen to save a lot of weight, standard battery is 6.4kg...

I figure i shall need to replace the battery before long, its got to be on the way out for its age if nothing else, really surprised its still there, and working...

Cheers Jeremy

what you are describing will put a brutal drain on proposed Shorai LFX21 ... turning motor off for several minutes with about 11 amp draw, if your bike has 2x 55watt headlights. then starting motor ...

then repeat for unknown number of times in traffic without allowing engine ample time to charge battery back up.

Shorai LFX 21 measured about 6 amp hour under a 1C discharge ... this means that battery will sustain 6 amp drain for one hour. or 30 minutes under 12amp discharge.

your headlights don't understand PB/EQ .. they drain real amps.

my recommendations are Odyssey 925 with 26AH, unfortunately 24lb... otherwise Shorai LFX36 with about 12AH (actual) might do it .. if you charged to full before you started and your total down time not exceed 60 minutes @ 12amp drain.

you'd be better off turning off bike with key, killing everything including lights during stops

watch this video, which stress LFX18 battery very similar to what you described
<iframe src="http://www.youtube.com/embed/-nm7bl39uxk?feature=player_embedded" allowfullscreen="" frameborder="0" height="360" width="640"></iframe>

Les, charger advertizing and promises of "hope" are as bad as oil additive snake oil ads. I am amazed what junk some of the well known charger manufacturers sell, and high priced at that.

We tested several chargers here at our Defense labs and the Xantrex TrueCharge 2 was by far the best. We bought a slew of them. And when I say "tested", we tested all aspects of them; current, voltages, temperature compensation, fault and alarm indications, etc.

They are available in various outputs. Note only the 20, 40 and 60 amp units can take a remote battery temperature sensor (most chargers put them in the charger ) and the remote panel enabling you to reduce the max current rate.

These aren't toys and as a result cost a few hundred dollars. But they do handle all types of batteries: FLA, AGM, GEL, Pb-Ca.

I have some pics here.

From the home of the plain old low-tech flooded lead acid battery, now in its 14th year and still starting my car at -20F.

Thanx for that. I was aware of that charger and that it was rated pretty well. Finding a place that does good reviews of this type of charger is hard to find. And most of this stuff is Rebadged Reptile renderings as was noted.

Do you kow of a good website for this type of battery related stuff? Car batterries as well?

What did you think of that CTEK charger?

Not really. Magazine and web-based sites that do evaluations are shallow at best. Understandably since your average consumer couldn't argue any of the results.

Check out Battery University and the East Penn Technical Manual (AGM & Gel battery paper)

For the money, its OK and no better or worse than anything else in that price range.

I brought both of my 3300 Multi US models in to our lab and had a Graphtec monitor voltage and current during charging. I never did see the float mode that is advertized. It goes to 14.3V (in normal battery mode), then shuts off and restarts at 12.5V which is my prefered method of charging. When I used a manual charger, I would monitor the voltage and when fully charged, disconnect it. When it self discharged over a few months to 12.6V, I would connect the charger again. That was for a battery out-of-vehicle. I use a HP DC supply at the moment (I'm the microprocessor and charging algorithm ).

I have 2 HP power supplies that I was going to wire in series to give 24 vDC / 1600w to go into an iCharger or Cellpro PL-8. I was wondering about going this route versus the Xantrex you mentioned? I still have those power supplies.

The Xantrex 40 and 60a models want a pretty good sized minimum bank of batteries and I can't meet that if I just hook up a PC925 without my other batteries.

thanks very much for sharing!

flooded PB amazingly still has it's place. when taken care of will provide excellent service life. it's not that long ago when AGM was considered new technology. price points for AGM has come down enough for AGM to become mainstream. hopefully the same will happen with LiFePO4 batteries.

lithium iron phosphate batteries has one of the lowest raw materials costs of any battery. there is no shortage of iron on this planet. hopefully public's acceptance for LiFePO4 batteries will translate into higher volumes/lower costs.

Battery University has always been one of the best sources for technical information on the WWW. unfortunately it's weakness is a lack of depth for the most promising of all battery chemistries. LiFePO4 or lithium iron phosphate ... called Li-phosphate in chart below.

in the fast changing world of batteries ... there's always been a trade off between maximum energy density and safety.

lithium cobalt hands down wins the energy density prize. but scores low on the safety side and needs elaborate safeguards to prevent lithium cobalt batteries from going into thermal runaway like on Boeing 787.

LiFePO4 currently wins the compromise between energy density and safety. unfortunately corporate's rather large investments in lithium cobalt chemistries prevents/hinders it from moving forward. unfortunately costs/time for meeting Federal guidelines prevents/hinders change to much SAFER LiFePO4 batteries in critical applications like main ship batteries on Boeing 787.

The optional remote panel allows you to set 20, 40, 60 and 80% of the charger's rated current. Its an additional cost, but has many other features as well.

As for the power supplies, as long as you are willing to do the monitoring.

You bet it does and when it does everything needed, it is all one needs for vehicle use.

Why would I pay twice or three times the cost of my FLA battery if I don't get twice or three times the life out of a lithium battery. Careful now, I get roughly 10 years out of a seasonal battery and 18 years out of a car battery.

Starter RPM? Who cares as long as it starts which it does on the first second.

Weight? Who cares; your average person could stand to shed 20+ pounds.

I see GM lost one of their test facilities. Hmmmm.

Any issues jumping a weak Shorai or other lithium battery from a regular 12 volt motorcycle battery with good cables?

So what is the secret to getting 14 years from a car battery? Been using a smart charger for a little while on all my vehicles "every now and then" expecially in the winter months. Got 7 1/2 years out of one. Any thing I could do better?

an excellent question ... the short answer is no issues jump starting a low LiFePO4 battery with a PB battery.

think voltage/current in terms of water flowing through a pipe.
volts = pressure of water
current = flow of water ... larger the pipe, more water flows through

LiFePO4 = low internal resistance = Huge pipe
PB = high internal resistance = little pipe

a fully charged PB battery is 12.85v flooded PB to 13v AGM.

a fully charged LiFePO4 battery is 14.6v to 12.8v at 20% condition. so very little current will flow into discharged LiFePO4 battery from a fully charged PB battery.

lithium batteries has very low internal resistance and will accept a charge at about same rate as discharge. for instance if a LiFePO4 cell is rated for 28C momentary discharge... that cell will accept a charge at that rate too. which could be very bad for low LiFePO4 battery, if hooked up to another fully charged 14.6v LiFePO4 battery.

most LiFePO4 cell mfg spec charge rates at .5C to 1C charge rates to allow time for cell to absorb current.

this issue comes up in series/parallel battery pack configurations. when/if one cell goes bad, rest of cells in nearby parallel stack will attempt to charge up bad stack. resulting in a pack that will never reach full charge. worst case a melted down battery.

which brings up one of the main advantage of LiFePO4 cells ... it's very difficult to cause a LiFePO4 battery to catch on fire ... then resulting fire will not be any where close a catastrophic, thermal runaway like lithium cobalt battery used in Boeing 787.

CY...
Ok cool, thanks heaps for sharing your thoughts and wisdom...
I never related to the headlight using so much power, currently has a H1 Bulb, 55w halogen, one only, but by the time we add in tail light, stop light, ignition, indicators, and a hit on the starter motor, i can see the battery getting a hard time...
That said this scenario isn't a often event, but just an extreme that got me thinking, given its summer time, and while stop start riding the other day i decided to shut her down each time i had to sit at a red, try keep the engine temp down being air cooled and all...

I see the big 36 Shorai is up in the mid $300 range, so that will be more toward $500 of my money, time it gets here, so thats out...
How long would you expect a BMW Gel 19ah to last, Im very suprised having just bought my bike, to find its original battery still in there and going ok...

Also just started using a charger, CTEK XS3600, But have been using on motorbike mode, and now just read online i need to use the car mode, Is it a good idea to use often and leave on for extended periods, my bike seems to be out maybe once a week currently, but less when winter comes...

Just a thought, How good a job does the BMW bike system do at charging the Shorai type battery, as it wasn't designed to do so... Think the listed output on my bike is 600w...

Thanks for the very informative thread to...

Cheers Jeremy

almost all 12v charging systems operate from 13.8v to 14.2v which mates perfectly with LiFePO4 batteries. since max charge occurs at 14.6v for LiFePO4, it's impossible to overcharge with a normal charging system.

properly taken care of PB based batteries can last a very long time indeed. best condition to store PB battery is fully charged.

AGM has the lowest self discharge rate for PB (LiFePO4 self discharge is lower yet) & tolerates overcharge abuse better than gel. which should not be charged over 14.2v-14.3v .. Gel batteries if overcharged can gas causing permanent damage.

AGM can also be damaged by overcharging but it's closer to flooded PB for charging characteristics. Flooded PB are most tolerant to overcharge of all the lead acid batteries.

600 watt charging system should be plenty to support most any electrical needs on your bike. Airheads got by with under 280 watts for decades. upgrades for Airhead charging system is only 450 watts.

Odyssey 925 AGM 26AH, weight 24lb vs Earth-X ETX36 at 3lb 11oz
recommendations is to go with AGM unless saving weight is more important than saving $$$.

Since we're talking charging here...

How about the use of the 14.7 v regulators and the PC680 or PC925 batts. Is that high output regulator too high for the AGM batts?

14.7v regulator would be on the high end of what an AGM battery will tolerate. sulfation/batt life would go down, capacity would go up... you are better off under 14.2v for longer life.

for a few months during testing for Shorai LFX 21 .. determined actual AH capacity was too low for R80G/S when combined with cold weather/heated gear/short trips. a higher output voltage regulator 14.4v-14.5v was tried ... conclusion was one still needed a larger AH capacity battery. but overcharging risks increased during extended rides. switched back to OEM voltage regulator. technically LiFePO4 reaches full charge at 14.6v, so 14.5v would still be under threshold. too close to LiFePO4 limits for extended rides...

this document is worth reading ... contains information specific to AGM 12v batteries. PB chemistries are well established technologies with a voluminous amount of information out there. key is knowing which set of technical information to drill in on.