TECH: LITHIUM BATTERIES
By Chad de Alva
Lithium motorcycle batteries are one of those products that always seem to make for some quality reading in the comments section when someone posts something online about one. It’s like asking the collective internet who makes the best pre mix, or what tire pressure is best – there is an endless supply of opinions and experiences on the internet. Yet, what worked great for Bob may not produce the same results for Bill, and even the best product out there won’t perform as advertised if it isn’t used and cared for properly. So this article takes a pile of information sourced directly from Lithium Battery manufacturers and battery charger manufactures and lays it all out on the table. The goal here is to share accurate information so that prospective and current lithium battery owners can follow the best practices out there to get the most out of their current and any future lithium Motorcycle Batteries.
WHY LITHIUM
In motorcycle applications, lithium batteries offer a number of advantages over traditional batteries. This is why some OEMs are selling new bikes with lithium batteries, and many riders are replacing their lead batteries with lithium batteries when their bikes need a new battery. A deep dive on the differences between the two types of batteries could easily fill a physics textbook (remember those?). So here is a quick summary of the differences between lead and lithium to keep things constrained to an article that can be consumed in a single serving.
Lithium motorcycle batteries weigh less than their lead-based counterparts. In many cases, we’re talking pounds of weight savings. This is one of the big reasons why OEMs are making lithium batteries standard equipment. Lithium batteries also provide more Cranking Amps (CA), and have a lower self-discharge rate. This means more power to turn your bike over, and a longer shelf life if you store your bike. Lithium batteries are more vibration and shock tolerant than lead batteries, and they can also be mounted in any orientation, where some lead batteries have to be kept right side up. Lastly, thanks in part to the Battery Management System (BMS) found on most lithium batteries, their lifespan is often significantly longer than a lead-based battery which has no form of management system.
DROP IN PERFORMANCE
Think of a Battery Management System as a little computer built into a lithium battery that controls how the battery functions. Some brands of lithium batteries have more advanced versions of a BMS than others, and we’ll talk about those advanced features in a minute, but any quality brand of lithium battery can be run in a late model bike without issue. The BMS will manage the charging voltage and current supplied by the bike to make sure that the cells in the lithium battery are properly charged and balanced, so the whole battery can work as advertised. In most cases, switching from lead to a lithium battery is as easy as selecting the correct size lithium battery, fully charging it, and installing it in your bike.
The one exception with bike compatibility is an issue with classic bikes, or bikes that have a mechanical voltage regulator. It is possible for these mechanical regulators to get stuck or fail in a way that their output voltage is outside of what the BMS can handle, so if you’re going to use a lithium battery in a bike that has a mechanical voltage regulator, make absolutely certain the regulator is working properly before you drop in a lithium battery.
READ THE MANUAL
If you have a bike that came with a lithium battery from the factory, it’s absolutely worth reading everything in the owner’s manual about how to properly use and care for the OEM battery. In the case of KTM Enduro (dirt) bikes that come with lithium batteries, the manual has a specific starting procedure for lower temperatures, because lithium battery performance is impacted by colder weather. The following starting procedure comes from the KTM manual, but the overlying concept applies to any lithium motorcycle battery. When the cells in a lithium battery get cold, they aren’t able to output the same amount of current as when they’re warm, so the cells need to be warmed up with a gentle load so they can handle a big load, like starting a cold bike.
First, engage your bike’s cold start. Then, simply give your bike’s starter a quick tap to create a little bit of load. Now, wait at least 30 seconds before trying to start the bike again. If the starter seems sluggish on this first starting attempt, wait another 30 seconds before trying again. The KTM manual states that you shouldn’t crank the bike for more than 5 seconds every 30 seconds, so be patient. Using this procedure has worked great for me and my KTMs in cold weather – and I convert my KTM 500 to a snowbike every winter. Using both OEM and aftermarket lithium batteries and this starting ritual, I’ve had no issues getting my bikes going in the cold.
If you are installing an aftermarket lithium battery into a bike, it’s also a great idea to read the manual that came with the battery. Remember, we’re dealing with batteries that have computers inside them, so this is not the same thing as a standard AA lithium battery. If you get nothing else from the manual, know that you need to fully charge the battery before you install it in your bike, and make sure to determine the maximum safe current at which the new lithium battery can be charged. Throwing too much current at a battery can lead to explosive results.
EXTERNAL CHARGING
To charge that brand new lithium battery prior to installation, or to plug your lithium battery equipped bike in for long term storage, you’re going to need a battery charger. The best way to charge a lithium battery is to use a charger that has a lithium charging profile. Any quality brand of charger will work, but I’ve personally had great luck with CTEK and NOCO Genius chargers. For motorcycle batteries, a 1-Amp charger is plenty of power for general charging and storage use. Yes, you can certainly feed these batteries more current, just please check your specific battery and/or your bike’s manual for the maximum recommended charging current. And, please don’t use a cheap discount store charger. Not burning down your bike and whatever it’s parked in is worth the cost of a proper charger.
Lead battery chargers can be used with lithium batteries, the key thing is to make sure that you turn off the desulfate features on the lead charger if it has one. If you can’t turn off any desulfating functions, or you aren’t sure, just don’t risk it. When lead battery chargers go into desulfation mode, they crank up their output voltage, which can harm a lithium battery and cause bad things to happen. You do not want to over volt a battery. I would strongly suggest that you spend a few bucks to get a dedicated lithium charger, so you don’t have to worry about turning features on and off. A lithium battery charger will make things plug and play.
ADVANCED BMS FEATURES
Just like some computers are much more sophisticated than others, some brands of lithium batteries have a BMS that has more features than other brands of batteries. Antigravity Batteries make arguably the most advanced BMS around, and their Re-Start batteries offer a very valuable feature. Say you left your key on, or you left your GPS powered on when you finished riding for the day. A normal battery will just supply power until it’s totally dead, and you get the distinct pleasure of finding a dead battery in your bike the next time you go to ride.
With a Re-Start battery, the BMS is smart enough to turn the battery off before it’s fully discharged. This does two important things: First, it saves the battery from damage as a result of over discharging, and most importantly for the rider, there will be enough juice in the battery to start your bike up. To use the Re-Start feature, you simply have to press a button on the battery to turn it back on, then crank your bike over and go ride for a while to get some charge back in the battery. If you are only able to go for a shorter ride, plug your bike in when you get home to ensure that your battery is fully charged for future use.
Other brands of lithium batteries, like those sold by Firepower, have a BMS that features an integrated test gauge where you can press a button and see what your battery’s state of charge is. This is an easy way to see if your bike needs to be plugged in if it’s been sitting for a while and is much easier than hauling out a multimeter to get a voltage reading.
PUTTING IT ALL TOGETHER
Lithium batteries work great in motorcycle applications. When you’re switching from a lead battery, you can save several pounds of weight, pick up additional starting power, and have a battery with a longer service life and warranty than the lead battery that you are replacing. So if you have a lead battery that is getting tired, give a lithium battery a try. Likewise, if you just want some drop-in performance and weight savings (less weight means more bike performance), a lithium battery is an easy way to do that. Pick up a battery charger with a lithium charging mode if you do not have one already, and then enjoy trouble free performance for years and years to come. Starting a bike in warm (above 60 degrees Fahrenheit) weather is business as usual, and starting in the cold works well if you follow the proper procedure. If you go with an Antigravity Battery that has Re-Start, you’ll have the valuable peace of mind in knowing that even if you drop the ball and leave something on your bike powered up, your battery is smart enough to protect itself and your ride, by shutting off before it becomes too discharged.
Like any other product out there, lithium batteries can fail to work as advertised if you do not follow the directions and use them properly. So please, read the manuals! If you just drop a new lithium battery in a bike without charging it, and then try to start the bike by holding the starter down, you could very well kill your new battery. Do things right – charge the battery before you install it. Start your bike correctly in colder weather by following a process that lets the lithium battery warm up first. If your bike is hard to start right now, figure out why and fix it. Even the best battery in the world is going to have a hard time starting a bike that has other mechanical issues.
In more than four years of running lithium batteries, the only time I’ve had one die on me was entirely my fault. Let’s just say it involved forgetting a key, then jumping a connector to remove said forgotten key from the equation, and then forgetting to remove said jumper, which led to a dead battery. Other than that, I’ve had zero issues. I’ve run lithium batteries on snowbikes, dirtbikes, and ADV bikes, and they’ve all worked great. I use a lithium battery charger for all of my initial charges and maintenance charges, and I’ve had no problems.
