HAS LITHIUM-IRON KILLED THE LEAD ACID BATTERY?


MXEditor

Many new technologies are maturing every year and for motorcyclists, one big change coming is the way we power our bikes…because there’s a new option when picking batteries and it’s called Lithium-iron phosphate.

 

In this article, we compare & contrast the key differences between the standard, "tried and true" lead acid battery and newer Lithium-iron phosphate units. Hopefully we'll help you answer the question of what's the right battery for your needs and budget. Maybe you already know and we'll just confirm this or possibly challenge some conclusions? :thinking:

 

Click on to the next page to see what we learned...

 

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Next page: How Do They Work?


 

HOW DO THEY WORK?

 

We are discussing two types of batteries here, Lead Acid and Lithium-iron phosphate (specifically the Shorai LFX Lithium-iron Battery Series), so let’s take a look at how each one works:

 

LEAD ACID

 

Italian physicist Count Alessandro Volta (where the term “Volt” comes from) first created a simple battery from metal plates and brine-soaked cardboard or paper in 1799…and the basic technology hasn’t strayed too far from that original design.

 

Lead Acid batteries are now manufactured with a hard plastic shell containing small compartments that hold both conductive plates (positive and negative) as well as acid (electrolyte) normally in groups of six. Sometimes these have external packages of electrolyte solution that you add and then charge the battery and some are sealed with the solution already installed.

 

Simply put, these lead plates are coated with either lead calcium (positive plates) or lead antimony (negative plates) which reacts with the electrolyte solution (normally sulfuric acid) in what’s known as an “electro-chemical reaction” that causes the plates to create electrical energy.

 

LITHIUM-IRON PHOSPHATE

 

Lithium-iron phosphate batteries are also manufactured with a plastic shell, but inside it’s quite different than the Lead Acid type. Inside the case, they contain both positive and negative electrodes as well as electrolyte, but the electrolyte normally a non-aqueous chemicals like ethylene carbonates and various lithium salts.

 

The electrodes are made from different materials. The positive electrodes are generally made from layered oxide or phosphate, while the negative electrodes are generally made from graphite.

 

Also inside you’ll find a separator which is a sheet of very thin micro perforated plastic and it splits the electrodes while allowing ions to pass through. When this battery type charges, Lithium-ions move through the electrolyte from positive electrode to the negative electrode and during discharge this process is basically reversed.

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Next page: How Long Do They Last?

 


 

HOW LONG DO THEY LAST?

 

LEAD ACID

 

Lead Acid battery life differs due to environmental elements including excessive heat and humidity. Battery industry pundits claim that a lead acid motorcycle battery can last five years if cared for properly and in ideal environmental conditions, but that’s not the real world. With lead acid batteries, letting them lose their charge fully can cause harmful sulfation and the battery may not fully recover.

 

In our experience, if you are using your motorcycle three to four times per week nine months out of the year, keeping it fully charged and you keep it on a battery tender device in the off-season, you should see battery life of two to three years. Lead Acid batteries favor colder, dryer climates, so riders in areas with this type of weather may see even longer battery lives.

 

LITHIUM-IRON PHOSPHATE (Shorai LFX)

 

According to Shorai, their Lithium-iron phosphate batteries do not sulfate while sitting and do not suffer the chemical degradation (sulfation) that is common with lead acid batteries. Conditions that will shorten the Lithium-ion phosphate battery life include batteries sized too small for load conditions/wrong bike and failure to maintain the proper voltage when the battery is not being used.

 

Lithium-iron phosphate batteries can outperform and outlast traditional lead acid batteries under lab test conditions, with some examples showing the LFX Lithium-iron phosphate battery can provide more than 2000 cycles during 80% DOD (depth of discharge) testing, as opposed to 500-800 cycles for lead acid batteries under the same conditions.

 

So in theory, the LFX Lithium-iron phosphate battery should last from two to four times longer than the lead acid battery.

 

Next page: What Is The Required Maintenance?

 


 

WHAT IS THE REQUIRED MAINTENANCE?

 

LEAD ACID

 

Lead acid batteries don’t like heat, humidity or to be discharged fully…so don’t let them go dead while sitting in your bike in that hot garage.

 

In fact, letting the voltage drop below 12.4 volts can result in lower battery life in general, so if you aren’t riding, make sure to use a “smart” trickle charger like the units from Battery Tender.
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We’ve seen riders “top up” their batteries with spare electrolyte or distilled water. This can help with efficiency and maintaining maximum output but over time using distilled water will just dilute the whole mixture and thereby lose its effectiveness.

 

Tip: For long term storage of lead acid batteries, we remove the battery from the bike and put it in a cool, dry section of our workshop attached to the battery tending device.

 

LITHIUM-IRON PHOSPHATE

 

You can’t “top up” a Lithium-iron phosphate battery with electrolyte so it’s important to monitor the voltage and charge as necessary to keep the resting voltage above 13.1 volts.

 

While standard lead-acid chargers can be used with most Lithium-iron Phosphate batteries when needed, most manufacturers make a charger that is specifically designed to charge, store and maintain the specific product type used.

 

Tip: When storing a Lithium-iron phosphate battery, it should be disconnected from the vehicle, fully charged to ~14.4 volts and then it can sit for up to 1 year before recharging. Storing in cool, dry environments is preferred for lithium batteries.
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Next Page: Weight Savings and Performance

 


 

WEIGHT SAVINGS AND PERFORMANCE

 

Lithium-iron phosphate batteries have shown the ability to operate at a higher voltage range than the typical lead acid battery during cranking, resulting in quicker start times.

 

Some Lithium-iron phosphate batteries can be up to 80 percent lighter than their lead acid equivalents. This saves an average of 2-3 lbs. for dirt bikes, 6-8 lbs. for street bikes and 10-20 lbs for touring and cruiser bikes.

 

The difference in weight was even larger for our Honda XR650L as the recommended Shorai LFX19A4-BS12 battery (2.31lbs) is lighter than the lead-acid Yuasa YTZX9-BS (5.4lbs) specified for the bike by a whopping 3.1lbs…that’s huge.

 

We all know that weight savings is the Holy Grail when it comes to high performance motorcycles and many riders spend thousands on lightweight components like titanium fasteners and carbon fiber bits for their bikes, but it takes a lot of expensive lightweight parts to add up to the weight savings stated when using a Lithium-iron phosphate battery and we consider this to be one of the best (and most inexpensive) ways to reduce weight on your motorcycle.

 

These Lithium-iron phosphate batteries are surprisingly much smaller than their lead acid equivalents, and this caused some dismay when they were first released and the battery was loose in the battery tray/carriers on some bikes…but now many manufacturers include some adhesive-backed foam padding to take up the excess room.

 

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Next Page: Environmental And Temperature Considerations

 


 

ENVIRONMENTAL AND TEMPERATURE CONSIDERATIONS

 

Typical lead acid batteries quote their normal operating range as 14 -140 F while Lithium-iron phosphate units quote this range as 20 -140 F, so not a huge difference there, but what happens when temperatures drop below the recommended range?

 

LEAD ACID

 

When a lead acid battery is used below 14 degrees F, the battery’s ability to discharge current will decrease because low temperatures slow down the chemical reaction inside. Lower cranking amperage means less power to turn over your engine, which can be even harder to crank than in normal temperatures, due to thicker oil viscosity depending on oil type and grade used.

 

This phenomenon can be compensated with somewhat by using a battery with the highest CCA (Cold Cranking Amps) and AHr (Ampere-Hour) rating correct for your application, because under actual cranking conditions they will deliver considerably less than specified capacity.

 

Why? Because lead acid begin sulfating when only a small percentage of the capacity has been used, and their internal resistance rises as they are discharged, the actual capacity which can be used may be as little as 20% of the printed rating.

 

LITHIUM-IRON PHOSPHATE

 

At lower temperatures the output of the Lithium-iron phosphate battery is also adversely affected and it’s recommended that battery is fully charged after storage to improve performance in cold weather.

 

The good news is that Lithium-iron phosphate battery cells are capable of 80% discharge without damage and while retaining higher cranking output. As such, the actual usable capacity can be on par with 18AHr-rated lead acid batteries while providing higher cranking performance and a reduction in weight.

 

There is a recommended procedure that can help compensate for the cold weather reduction in performance when using a Lithium-iron phosphate battery:

 

Turn on your headlight because it helps output for the battery to flow some current before cranking in cold weather. The suggested headlight-on time before cranking depends on the temperature. If starting at 40F/5C, 30 seconds will help wake the battery and increase cranking performance. If at 0F/-17C, leave the lights on for 4-5 minutes before cranking and thee result will be a better first crank and longer battery life.

 

If the engine fails to start on first crank, that first crank has warmed the battery, and the second attempt will be much stronger. Other accessories that can be turned on before cranking can also be used for this purpose, such as heated gear, GPS, etc.

 

Next Page: How Much Do They Cost?

 


 

HOW MUCH DO THEY COST?

 

We priced two batteries for our 2015 Honda XR650L - the Yuasa lead acid unit with 135 CCA was $92, while the Lithium-iron phosphate battery with 285 CCA’s was $189, so you’re paying for the higher cranking performance (almost double the CCA’s) as well as much lighter weight.

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Next Page: What Did We Conclude?


 

SUMMARY AND CONCLUSION

 

Although Lithium-iron phosphate battery technology is fairly new, it has significant benefits and few drawbacks at this point in its development.

 

Advantages of the Lithium-iron phosphate batteries include dramatically lighter weight, higher cranking amperage ratings per size of the unit, intelligent charging mechanisms and much less chance of corrosive material spillage.

 

The one disadvantage in this author’s mind would be the increased cost.

 

In conclusion, yes, we believe that Lithium-iron Phosphate battery technology is, except for cost considerations, “better” than the standard lead-acid battery and will be the Grim Reaper that makes lead-acid batteries obsolete as we move forward in time.

 


Have a burning question :confused: or need to inform us that we've missed something? :prof: Hit us up in the comment section below. We want to hear your thoughts & experiences on this topic!




User Feedback




Good article. I just got one for my CRF250L. In reading the manufacturer warnings it states not to submerge it or subject it to impacts.

So for a dual sport bike, what happens with these batteries if you're crossing a creek and drop the bike?

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I just got one for my cf250x and its really good so far and iv only kick started my bike about 3 time since iv had it and it was cheaper that the lead one?

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I've had a Shorai in my DRZ for 2 years and it always starts the bike, even in cold weather.  The weight savings is huge.  I got mine from the TT Store and thought they had sent an empty box by mistake, but I opened it up and there was a big battery in there.

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It is not wise to use a Battery Tender on a Shorai battery. They claim it will kill the battery because it doesn't charge the battery evenly. They recommend purchasing their charging unit. This adds to the cost. However, I have two off them and they appear to work better than the standard batteries.

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Most know the cost per pound for weight reduction so an extra $100 for this amount of weight savings is very cheap!! Then add in the benefits, seems a no brainer this way. If you look at just cost between each battery, doesn't seem so good. Look outside the circle. Good article.

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They are not all that they are cracked up to be. My local Dealer will no longer sell them because they have had more complaints than not. I bought one for my sport quad & the charger to go with it. I left the key on one to many times & it bit the dust. 

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I wish this article would address one additional point:  The environmental impact of each of these batteries.  I really, honestly don't know how bad a lead acid battery is for the environment.  I know they can be recycled, and almost any shop in my area is happy to take a spent battery for free, but the Lith-ion batteries, I dunno?  Are they harmless when their useful life is over, or do they do freaky things to the environment if you just discard them?  Where do I take them to recycle them?  I have grandchildren; I want to leave them a cleaner world than I inherited.

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Good article. I just got one for my CRF250L. In reading the manufacturer warnings it states not to submerge it or subject it to impacts. So for a dual sport bike, what happens with these batteries if you're crossing a creek and drop the bike?

 

 

Any answers to his questions?  If accurate that is a show-stopper for my dirt bike or for that matter my off-road R1200GSA..

 

Saving 3.2 pounds?  Seriously on a race vehicle that is significant..

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I had a bunch of Shorai's.... nothing but problems. And their charger is comical- looks like it was made in a high-school electronics class.

I love some of the pluses but there are a LOT of negatives with these batteries.

I still feel like the LI batteries are not quite ready for prime time..... I don't know.

Also- I'm an off-road guy and I think street people have a different experience.

Also- I thought it was "Lithium-Ion" but this article is calling them "Lithium-Iron"........?

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Most I know, myself included gave up on lithium , went back to agm.

I have a lead one in my KTM right now- and that's what I will stick with. LI has been a PITA!

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Tried the lithium iron in my BMW f650. The entire electrical system was affected by the battery's internal charging circuit. Voltage levels were all over the place. Horn sounded like a dead frog, turn signals went spastic. Replaced the regulator and stator. No difference. Finally, the lithium died taking out the regulator also. Replaced with lead acid, all was restored. The technology is premature. Need better internal circuitry.

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Good article. I just got one for my CRF250L. In reading the manufacturer warnings it states not to submerge it or subject it to impacts. So for a dual sport bike, what happens with these batteries if you're crossing a creek and drop the bike?

 

Many dual sport riders report no issues but some folks in these comments

have mentioned some for sure!

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I've had a Shorai in my DRZ for 2 years and it always starts the bike, even in cold weather.  The weight savings is huge.  I got mine from the TT Store and thought they had sent an empty box by mistake, but I opened it up and there was a big battery in there.

 

Any issues with durability? Was the DR-Z a off-road model?

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I wish this article would address one additional point:  The environmental impact of each of these batteries.  I really, honestly don't know how bad a lead acid battery is for the environment.  I know they can be recycled, and almost any shop in my area is happy to take a spent battery for free, but the Lith-ion batteries, I dunno?  Are they harmless when their useful life is over, or do they do freaky things to the environment if you just discard them?  Where do I take them to recycle them?  I have grandchildren; I want to leave them a cleaner world than I inherited.

 

Great questions here - batteries are bad stuff in general

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I had a bunch of Shorai's.... nothing but problems. And their charger is comical- looks like it was made in a high-school electronics class.

I love some of the pluses but there are a LOT of negatives with these batteries.

I still feel like the LI batteries are not quite ready for prime time..... I don't know.

Also- I'm an off-road guy and I think street people have a different experience.

Also- I thought it was "Lithium-Ion" but this article is calling them "Lithium-Iron"........?

 

Typo in the email that was sent but the article text should be correct!! :)

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Tried the lithium iron in my BMW f650. The entire electrical system was affected by the battery's internal charging circuit. Voltage levels were all over the place. Horn sounded like a dead frog, turn signals went spastic. Replaced the regulator and stator. No difference. Finally, the lithium died taking out the regulator also. Replaced with lead acid, all was restored. The technology is premature. Need better internal circuitry.

 

Wow that sucks! What kind of battery was it?

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I also had a few of Joe Turner's TurnTech batteries and had better luck with them, And his service was unreal! Miss him!

They went out of biz, right? I heard it was a good product!

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I don't know about life on a lead acid being short; I top mine off once a month and right now, I'm on year six.

 

Like anything, good maintenance makes a big difference.

 

Jim.

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I've had an EarthX lithium battery in my Ducati Multistrada for 3 years now. It works so much better that the acid battery ever did. I think the EarthX is superior to the Shorai since it has special circuitry that allows a normal tender to be used. It also has protection from over charging and over discharging. Mine sat for a bit to long and i thought it was dead since the trickle charger wasn't charging it until i gave it a boost for 30 seconds with my truck battery. Then the trickle charger worked on it. This is the best battery I've ever had.

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I'm currently running a Bikemaster LI, but it's too early to say how reliability will be. But, my bike def cranks faster than the stock lead acid Yuasa. And, the weight saving was almost 9lbs!

 

My last LI battery was made by SuperB out of the netherlands. I never charged it and it sat through a couple of Colorado winters and a couple of Vegas summers before I sold the bike. So almost 5 years old, zero maintenance, and good performance. There are some good brands out there. I've not tried Anti-gravity batteries, but i know they have a strong warranty.

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To Aristocrat. On impact,...they blow up. I've had one for my Ducati 998. Finally a battery that started it regularly. But a second tuner I have who runs a Ducati race team stopped using them because if you crash,..your bike blows up,..catches fire.

So it happened to him.

I have crashed a few times with that battery in it and nothing happened. My first battery went to sleep over the winter and my motor guy said he figured a way to wake it up,...that battery lasted 2+ years. I bought another one that lasted 6 months and Shorai sent me another better one free. So they support there product that is for sure. I was told they would replace mine when they received it,..but I got my new one the day after I sent mine back. My hat goes off to them.

I just sold my Ducati with that fresh battery in it and will see what I put in a vintage 2 stroke I am having built. They sure are light.

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Although its a very slim chance , lithium batteries can catch fire or explode spontaneously. I know its a very rare occasion but I'm not gonna take a chance on it.

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      Joe
       
       
       
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      My youngest son was riding is PW50 and went down at a slow speed (no injuries) and the bike hasn't ran right since...Its an 85 yz50 that I bought for next to nothing. ($75) Replaced most of mechanical/cosmetic parts (top end, crank bearings/seals, tires, wheels, body work, bars, etc.) But haven't done anything with the electric until the recent crash. The bike was getting little to no spark immediately following the crash so rather then sit there he just jumped on his other pw50 for the rest of the day. With the bike being so old I just opted to replace with new electrical components/wiring.
      New parts-magneto, harness, factory bar switch, CDI, control unit, flywheel, ignition coil, and spark plug.
      Plug and play right? Nope still no spark and the magneto is putting out around 28 volts on Black/Red wire and ground when I kick it.
      Any ideas where to check next? Thanks in advance!