Lithium ion and lead acid batteries on ATVs, UTVS and snowmobiles. Lithium Batteries for UTVs and ATVs
Powersports battery review
Copyright 2010
Gary L. Gustafson


Lithium-ion Batteries Are Starting To Arrive
The next generation of battery technology is arriving, with Shorai and Flux Power delivering Li-ion starting batteries and Deep-Cycle batteries, respectively. Ever-tightening environmental regulations have created a need for new types of drivetrains such as hybrids and plug-in electrics. Electric motors in these vehicles require enormous power. Even on gas-powered ATVs "by-wire” functions such as Electric Power Steering demand a lot of current. Nickel-Metal Hydride and Lithium-ion battery packs are both seeing use on automotive hybrid and plug-in electric drivetrains because of their superior energy and power densities.  However, these advanced designs come at a price that is generally between six and ten times more per kWh than a lead-acid battery with equivalent energy.

While lithium-ion batteries have a higher energy density than nickel-metal hydride, and create less environmental damage, they are also more volatile and more expensive. It is notable that the 2010 Honda Insight has been developed with an NiMH battery pack. Generally speaking, however, lithium-ion cells are prevailing and are projected to eventually replace NiMH. The next generation Prius is slated to carry lithium-ion, as is the Chevy Volt and the Nissan Leaf. The cost-up for advanced batteries is hindering their introduction on powersports vehicles in the near term. Li-ion and NiMH packs also may require air cooling, a major obstacle for off-road vehicles used in dirty, muddy conditions. However, as economies of scale for cell manufacutring develop concurrent with stricter environmental regulations, the long-term prospects for advanced battery implementation on powersports machines are excellent. In the meantime, the lead-acid battery is still an optimized, mature design that has filled a need for starting gas-engine motorcycles and ATVs very well. In short, to paraphrase Sir Winston Churchill, "it’s the worst form of battery there is, except for all the others. "

Introduction to Lead-acid batteries

Relationship between the Charging System and the Battery
As with many electrical technologies, the battery and charging system are a little fuzzy in the minds of many consumers. And if the truth be told, even service technicians sometimes have a hard time separating the two. The battery and charging system are directly related, but actually each has it’s own purpose. The charging system on an cycle or quad needs to support all of the high duty-cycle (frequent, long-term) electrical loads AND keep the battery charged as well. Examples of high duty-cycle loads are: Cooling fans, headlights, and accessories such as pull-behind sprayers that draw a lot of power and are on for long periods. The battery alone cannot support high duty-cycle loads because in most cases an ATV battery’s energy storage capacity (measured in Amp-Hours) is actually pretty low. Batteries with low amp-hour capacities are used on motorcycles and ATVs to reduce weight, for easier packaging, and to reduce cost. The “so what” of this is: if the loads on the electrical system exceed the charging system capacity, even a large battery will go dead, sooner or later. The battery is meant to handle low duty-cycle, high current electrical demands like starting the engine and winching.  In other words, the battery on most ATVs is built to deliver a lot of “juice” for a short time. Batteries also stabilize the voltage on the DC power bus, helping all components to operate without malfunctioning.

A battery is most properly viewed as being like a tank of gas that should be topped off on a daily basis.  In most cases the bike's charging system will perform this operation, but in some cases the operator must take responsibility for charging the battery. As will be explained shortly, when in doubt, use a battery maintainer or tender when you park your quad, and leave it on until the battery is re-charged.

There are really only 2 Lead-acid Battery types
The terms “Gel Cell”, “Sealed”, “Maintenance-free”, etc. are often used when comparing battery types. The fact is there are two basic types of battery technology in use on ATVs today—conventional (also known as flooded) and AGM—short for Absorbed Glass Mat. All other terminology are simply different ways to describe these battery types. Conventional battery technology is just that. It has been around for many, many years. AGM batteries are a little newer. They were pioneered on Honda powersports vehicles in the early 1980s (with an expensive learning curve) but have since become by far the prevailing battery technology on motorcycles, ATVs, snowmobiles, and personal watercraft. The innovative “spiral” cell batteries from Hawker and now Johnson Controls are just a different way to implement an AGM battery. Here is a brief comparison between the 2 battery types:


















Fig. A: AGM Battery Design Courtesy Yuasa Corp.


Comparison Table

CharacteristicConventional Battery           AGM Battery
Other common names:Flooded  Sealed, Gel Cell*, VRLA,        
Specific Gravity of Electrolyte   1.2651.310
(at 77F)

At-rest fully-charged voltage      12.6-12.812.8-13.1
(no loads)**

Filler cap type   Removable          Permanently installed

Typical Housing Colors       Natural, White     Black, Grey

Needs distilled water refills?      Yes   No

Use bulk acid to activate?   Yes         No.               

Can be installed at an angleNever                    Sometimes

Has a vent hose?    Yes (On ATVs)    No

*There is a separate Gel-cell design, but it is not used on any ATVs
**After 24 hours at rest to allow “surface charge” to dissipate.


Almost 100% of the time, when people talk about sealed, Gel-Cell or maintenance-free batteries from any manufacturer on a powersports vehicle, they are actually talking about AGM technology. Absorbed Glass Mat refers to the battery’s design in which all of the electrolyte (acid) is absorbed into fiberglass-pads that are pressed between the positive and negative plates. There is no loose acid in a properly-activated AGM battery. Conventional batteries must have extra acid above all of the negative and positive plates. Dry plate surfaces become damaged and that is one reason why conventional batteries must be topped off with distilled water as needed.  AGM batteries are not vented to atmosphere so they do not dry out with normal use. One thing that should be noted is that while the basic technology is the same regardless of manufacturer, there are varying levels of quality from manufacturer to manufacturer. The familiar names in lead-acid batteries do have a longer track record of quality than many of the newcomers do.

AGM batteries have several advantages over conventional batteries. They will have much higher cranking capacity for the same weight than a conventional battery will. They do not need to have distilled water added, ever. They can be installed at an angle—but ONLY, ONLY if they have been perfectly activated. They generally have a higher amp-hour rating for the same weight than a conventional battery will. Lastly, they do not have a vent hose to deal with because vapors are contained and re-combined into the electrolyte as part of the design.

The disadvantages of an AGM battery are that they are very sensitive to how well they are initially activated, they cost more, and the misnomer “maintenance-free” often misleads people to think they do not need to be concerned with charging them. An AGM battery needs to be kept properly charged every bit as much as a flooded battery does, and they require more complex equipment to both activate and charge them than a conventional battery does.

Initial Activation of New Batteries is Critical
A new lead-acid battery be trickle charged for at least 8-10 hours at between 1 and 3 amps (depending on battery size) on a charger designed specifically for powersports vehicle batteries—not a car battery charger. If the dealer selling the battery makes comments like “The quad can charge the battery. Just take it out for a drive when you get it home” or “The battery is charged when you pour new acid into it” or “We use a rapid-charger, it’ll only take an hour and the battery will be ready” it is a clear sign that the dealer is ignorant of best practices with batteries.

Tests I have performed indicate that a battery can lose substantial capacity, permanently, if it is not properly activated. This capacity will be missed if the ATV needs to be started on a cold day to plow snow or when winching your way across a long swamp. Time must be allowed for the electrolyte to soak into the fiberglass matting thoroughly before a charging voltage is applied. In addition, both proper voltage and current must be administered for the battery to be properly activated. That is why a “smart” charger designed for AGM batteries must be utilized for the initial charge. Models I recommend include the Yuasa Smart-Shot 1.5 Amp charger, the Christie chargers that have been mandated to Honda’s dealers and Tecmate models that are mandated at some Yamaha dealerships. These chargers have all been developed specifically for AGM battery technologies. They will charge the battery at the right current and voltage if they are utilized correctly by the technician who is doing the set-up. Low-current battery tenders, typically in the 900 mA range, are not adequate for the initial activation of the battery. Some, such as those made by CTEK, are excellent at maintaining the battery once it is in service.

The best dealerships constantly anticipate which batteries are going to be installed on their machines and keep a supply of batteries charging at all times. AGM batteries that are put on a smart trickle charger can be charged for months, as needed, with no damage to them.

What is sulfation and de-sulfation?
Without getting too technical, sulfation is a permanent, hard coating of lead sulfate on the battery plates. Areas of the plates that are covered with hard sulfate become useless. It is similar to cholesterol slowly clogging the arteries near one’s heart—you often don’t know there’s a problem until it’s too late. As sulfation builds up, the batteries capacity shrinks. It is like a gas tank getting smaller and smaller. When enough of the lead plates are covered with sulfate, the battery will no longer be able to store, and therefore, release enough current for the work needed, i.e. cranking an engine.

Complex battery chargers are available that can apply a de-sulfating voltage cycle to the battery. These chargers are expensive and usually only in use at dealerships, not at consumer level. It takes a higher than normal voltage to break down the sulfate and re-combine the sulfur ions back into the electrolyte as acid. When the process begins to work, as evidenced by increased current flow, the charger gradually backs the voltage down to a normal level. Chargers such as those made by Christie and Tecmate are purpose-built to perform the de-sulfating process and they work very well.  A battery that has discharged and sulfated can usually be brought back to at least 90% of its original capacity after it has been put on a de-sulfating charge cycle.No amateur should attempt any homemade process to de-sulfate a battery because of the risk of explosion. Battery acid will permanently damage eyes and breathing passages.
















De-sulfating Charger Courtesy Tecmate Corp.

Most Common Mistakes With Batteries
Many people have come to assume that their quad, or snowmobile, or motorcycle will need a new battery every year or 2. However, any modern power sports battery should last a minimum of 4 seasons and possibly as many as 7 with some basic care. One fact to be aware of is that in most cases battery damage accumulates and almost never corrects itself, so routine maintenance is critical. Here are some of the most common mistakes made with batteries:

#1 Parking the vehicle without being sure the battery is charged.
Once again—permanent, measurable damage (such as sulfation) can occur in as little as 1 week if the battery is left discharged. Sulfation accumulates and never reverses unless a de-sulfating charge is applied to the battery. If the battery is damaged enough times—presto! One morning the ATV will not start! Battery damage varying from minor to total failure can occur if a four-wheeler has been operated in the following ways:
1.The lights (including brake and tail) were on for a length of time without the engine running.
2.Plowing snow.
3.Using a sprayer attachment on the ATV.
4.Doing lots of winch work, whether getting across a swamp or for   utility purposes such as building hunting stands.
5.Parking the ATV or motorcycle with key-power on.

#2 Long-term storage with the battery installed
It is best to disconnect the battery on any powersports vehicle if it is going to be stored or parked for longer than a month. Nearly every modern bike has something called quiescent current draw that puts a continual, low-current draw on the electrical system. This draw will kill a battery in months, or even weeks in some cases. Sometimes on an older ATV the wiring insulation may break down enough to accelerate this process. The negative battery cable should always be the one disconnected so that no wiring can be short-circuited to the frame. If the ATV or motorcycle is going to be parked for more than a month, take the fully-charged battery off completely and store it in a cool, dark place.

#3 Using tap water to fill conventional batteries
It really is true that tap water shouldn't be used to “top off” a conventional battery. This is because of minerals in the tap water. Ever heard of e-coating? It uses electrical current to deposit molecules of paint. A similar process occurs in a battery if there are minerals present in the electrolyte. As current flows through the battery the iron molecules from your tap water get built up into a little formation that looks like a stalagmite in a cave. When this spike is long enough to short a positive and negative plate together, your battery life will be finished. In addition, minerals can build up in the bottom of the battery like scale in the bottom of a toilet tank. When the mineral scale in the bottom of the battery shorts a positive and negative plate together, the battery will never work properly again. Unless you like buying a new battery every year, use distilled water to top off the battery electrolyte.

#4 Using a car battery charger to charge an AGM battery
The weight and size of the starting battery as a percentage of overall vehicle weight is not an issue on ICE cars like it is on a motorcycle so AGM technology is not common in the automotive world. Therefore chargers made for car batteries are not designed for the AGM battery on a quad. A charger and/or maintainer specifically made for AGM technology should be utilized if the ATV is equipped with this type of battery. AGM batteries have a higher specific-gravity acid, and need a higher voltage to charge them than car batteries do. Also—some car battery chargers will not taper or “trickle” down the current as the battery charges. This will cause the battery to lose electrolyte by evaporating it through the safety valve. Since water can not be added to an AGM battery, the electrolyte that the car charger cooks off is gone forever, with a resulting loss in battery capacity. Battery tenders made for AGM batteries are very affordable and a simple 900 milliamp-level battery tender should pay for itself several times over via prolonged battery life. Good brands for this type of tender are—Yuasa, Midtronics and Battery Tender.

#5 Thinking that “Sealed” means “Maintenance Free”
A car battery called “maintenance-free” can be treated as such, but no battery on a seasonal recreational product should ever be considered maintenance-free. Because of the fact that ATVs and bikes have weaker charging systems than cars, and are left parked for months at a time (unlike most cars) a sealed battery will usually require some maintenance charging. The same is true for the battery on any power toy including boats.

Conclusion
Lithium-ion and NiMH battery packs are beginning to be implemented, but lead-acid designs will probably remain the primary technology as starting batteries on ATVs and motorcycles for some time to come. The main drivers that will speed or slow the implementation of advanced batteries will be cost and environmental regulations. Stay tuned!













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