Customers often ask us at Picture Me Rollin “which is the best Lithium motorcycle battery”?  Which can be tricky to answer, because of many variables.  Including which motorcycle they are being used in, how often they are used, and at what temperature they will be used.

THE FACTS

The popularity of Lithium batteries is increasing.  They are often promoted as a premium aftermarket option to replace the factory-fitted lead acid battery designed for your motorcycle.  When we think of Lithium starting batteries, the first things that come to mind are high cranking power and light weight.

LEAD ACID VS LITHIUM

There are many claims about the features and benefits of replacing a factory-fitted lead acid battery with a lithium alternative.

Before deciding to swap your motorcycle lead acid motorcycle battery over, do your research. 

1.       Read the warnings on the battery packaging.

2.       What are the effects of overcharging a lithium motorcycle battery?

3.       What are the effects of over-discharging a lithium motorcycle battery?

4.       What effects does heat have on a lithium battery

5.       What effects does cold have on a lithium motorcycle battery?

6.       How long do lithium motorcycle batteries last?

7.       Weight, does this really make a difference to performance?

8.       The battery management system – is the battery you choose protected or not protected?

What are the problems with lithium batteries for motorcycles?

A lithium battery may not be the best choice if you have a custom bike with many electrical accessories fitted.  It will do great starting the bike but may fail to run the accessory items like a winch for as long as a Lead Acid battery would.  Another issue is that Lithium does not perform as well as traditional lead-based motorcycle batteries when the outdoor temperature is at or below freezing (usually not an issue in most parts of Australia).  Lithium batteries will perform as normal down to about 5 °C, but as temps get lower, their performance degrades.  So, if you have lots of accessories like a booming stereo, winch, or lots of lights or ride mainly in below-freezing temperatures, you might consider going with a more traditional battery choice (i.e. lead acid).

Let’s look into this further…

READ THE WARNINGS ON THE PACKAGING

Lithium batteries must be used within their recommended parameters.  Replacing a lead acid battery with a lithium can be catastrophic.  As the labels on most batteries will clearly highlight, using the incorrect charger, overcharging, overcurrent, or short circuiting will damage the battery and compromise your safety.

Although many articles and YouTube videos claim you can charge a lithium battery using a standard lead acid charger, lithium battery manufacturers clearly state you must use a lithium specific charger.  Failure to charge your lithium battery within the manufacturers recommendations may have catastrophic results.

OVER-CHARGE

Overcharging a Lithium battery causes irreversible damage to the cells.  When a motorcycle charging system has a higher charging voltage than the manufacturers recommendations, the battery will overheat, causing swelling that can lead to explosion or fire.

OVER-DISCHARGE

Some Lithium motorcycle batteries are fitted with a Battery Management System (BMS).  The BMS protects the battery and activates the low voltage cut off when the voltage drops below 15.V.  This disconnects power to the battery terminals, putting the battery into sleep mode.  The battery can usually be “woken up” by using a special lithium battery charger.  If this reactivation is not successful, the battery becomes unusable.

Lithium motorcycle batteries without a Battery Management System don’t have low voltage protection.  Over discharging these batteries causes permanent damage to the cells and increases the risk of a fire or explosion.

HEAT

Motorcycles with factory-fitted lead acid batteries usually have the battery compartment in a high heat area.  This may be under fuel tank, above the cylinder heads, or in a side compartment that is exposed to heat from the hot exhaust system or engine.

These external heat sources can generate higher internal temperatures in a lithium battery.  The result is long term cell damage or temperature reaching critical levels resulting in venting flammable gases.

Motorcycles with factory-fitted lithium batteries are designed with the battery compartment at the back of the seat, away from any heat source to prevent overheating.

Where is the battery compartment located on your motorcycle?

COLD

Colder temperatures cause higher internal resistance in a lithium battery.  The higher the internal resistance, the lower the capacity.

Lithium batteries can also suffer from permanent reduced capacity or serious cell damage if charged in colder temperatures.

SERVICE LIFE

Due to the low uptake of lithium motorcycle batteries, there is no accurate data to validate claims that using an aftermarket lithium battery to replace the factory-fitted lead acid battery will deliver increases in performance or service life.

WEIGHT

There is no denying that lithium batteries are lighter than lead acid batteries.  Lead by its very nature is heavy and a good quality lead acid battery will contain plenty of good quality albeit heavy lead!

It’s appealing to consider replacing a lead acid battery with a lithium due to the lighter weight.  Motorcycles be design have high power to weight ratios, with modern supersports bikes having to close to 1:1 ratio (Hp to Kg) and therefore a reduction in weight on the road, seems irrelevant unless you are at the very cutting edge in a competitive environment.

BMS – PROTECTED OR UNPROTECTED?

Some Lithium motorcycle batteries are fitted with a Battery Management System (BMS) and some without.  The BMS protects the cells from over charge, over discharge and short circuit.  This helps prevent the risk of explosion or fire.

Motorcycles factory-fitted with a lead acid battery can have variations in charge voltages.  If an unprotected lithium battery was fitted and the charge voltage was too high (particularly at higher RPM’s) for the internal cells, the result would be irreversible cell damage and the risk of the cells venting flammable gases.

Even with a BMS, if the motorcycle charging system voltage is too high, a lithium motorcycle battery could be damaged when the BMS activates over-voltage protection.  This could cause failure of the electrical system.

In short, lead acid motorcycle batteries are far more tolerant of variations in charge voltage than a lithium motorcycle battery.

SUMMARY

In summary, it should be noted that whilst some lithium batteries provide excellent performance in deep cycle applications, when fitted in motorcycles designed for lead acid, there are still many challenges and unknown long-term repercussions despite years of research and development.

If reliability and performance is what you require, then using the original factory-fitted battery is the best option for your motorcycle.  For further information on this topic, please pop into our store here in Sydenham and speak with us to determine the best battery for your motorcycle or application/use.

Disclaimer:  The information contained in this blog has been put forward in good faith and is issued as part of product information.  Picture Me Rollin can accept no liability for any event arising from its use or interpretation.  Users agree that use of this information does not entitle them to make any claims against Picture Me Rollin or its staff members.