The cheap part of this is that it can save you hundreds in the cost of new batteries; I have had terrible luck with Batteries.  No matter how good a brand I buy I have often found my self junking batteries after only a season or less of use. The reason for this in my case is 2 fold, one I own multiple bikes so not all of them get ridden as regularly as is needed to keep the batteries getting a regular charge from the bikes charging systems and 2 I have found it to be a problem on bike with alarms not being ridding often enough the alarm slowly kills the battery. I simple and cost effective solution is a battery tender.

The "Battery Tender" is a low amperage battery charger, with a built in monitoring circuit which is designed to keep any battery at maximum "health" and will therefore extend the life of the battery, often by a year or more.  Where I used to change a battery every two years, I am generally running 4 years, and sometimes five.  I am famous for being dropped in the boonies by a bad battery.  Cycle batteries are small and take a lot of vibration/dehydration abuse.  I generally by the best stock battery available.  The Battery Tender is the one of the best, if not the best battery monitor on the market.  I use them on all my batteries, including auto and boat.  Buy the best.

The battery tender comes with a "lead" that will connect to the battery (left), and can be run down to one of the sides so the lead off the tender can easily be connected during storage (below).  

I keep my tender on 100%  of the time.  It is important to check you water level consistently, as a low battery is a sick battery, and a sick battery will die faster and leave you stranded (With me, in the middle of some northern forest, miles/hours/days, from being on the road again).  It cannot be overstated how important a healthy battery is for riding reliability.  Use a Tender and check your water level.  Use distilled water in batteries.  Remember the Vmax has a little window, where water level can be viewed by looking back under the seat from the front, without the Yamaha pox of going down from the top.

WHAT KIND OF BATTERY CHARGERS ARE AVAILABLE?
A trickle charger is the most common.  They charge at a fixed rate, and do not "know" when the battery reaches full charge, will keep running and can boil the battery dry and destroy it.  Watch them carefully, but since they are rather slow, that should not be a major problem unless you forget and leave it on for days.

Taper chargers decrease the amount of current moving into the battery as the voltage of the battery goes up.  But they still have to be watched carefully to prevent drying out, overheating, etc.  They are not a lot faster than trickle charges and have basically the same drawbacks. 

The pulse charger like the Battery Tender has a circuit which can monitor the  charge throughout the charging process.  The pulse charger decreases output to the battery as it becomes fully charged, then switches to a monitoring mode.  As the battery self discharges, and the voltage level drops below a preset point, the charger swings into action to bring the battery back up to full charge.  This is ideal for keeping the batteries chemistry in "good health" and especially for cycle batteries which are small and sit around a great deal of the time.

WHY AVOID TOTALLY DRAINING A BATTERY?
It is guaranteed that totally draining a battery 2-4 times will drastically shorten the life of the battery and as importantly, its capacity to deliver current is drastically impaired.  You have just ruined your battery.  DO NOT completely drain a car/cycle battery.  Sitting around over the winter or for prolonged time will do it, excessive grinding and load will do it, a slow draining load will do it.  

Well, of course the answer is to always use a Battery Tender, always keep the battery fluid at the correct level, always treat the battery with tender loving care.  Always keep you bike in good running order so it starts easily, and along those lines start and  take your  bike on a lot of 15-30 mile trips.

Another good idea is buy the best battery possible.  I think that is Yuasa.

SOME BATTERY SCIENCE
A cycle battery is small compared to an auto battery.  It is subjected to much more vibration and physical abuse.  It is often under load and rarely properly charged.

The typical cycle battery is made up of a case, positive plates, negative plates, plate separators, cell connectors, filler caps, and a sulfuric acid/water electrolyte.  It is divided into six individual cells, which are connected together.  Each cell is composed of a stack of lead plates separated by an insulator such as fiberglass or treated paper.  

The lead plates carry a charge and are connected to each other, positive to positive and negative to negative in the stack.  The positive plates are made of lead peroxide (PbO2), and the negative plates are formed of lead which is made with a surface that is very irregular or spongy looking, because a battery's capacity to deliver electrons or current pressure is dependent on the surface area of plates exposed the electrolyte.  

Each cell is connected to the next cell in series, positive to negative.  Each cell produces about 2 volts of direct current, for a total of about 12 volts for a healthy fully charged battery.  

The total output of electrons for a battery, thus the total "power" it can produce at anyone time is related to the number of lead plates in each cell, their size, their "health."  

The plates are bathed in a bath of sulfuric acid and water mixture, and there is a slow chemical reaction between the sulfuric acid and lead in the plates which produces lead sulfate and causes the constant release of electrons which create the charge at the surface of the plates and thus the movement/flow of electrons, which gather in numbers and force as they flow through the system of plates when a demand, or load is put on the circuit, such as hitting the switch for the starter motor.  An analogy would be turning on a faucet to pump water down a pipe to do work at the other end.

A LITTLE BATTERY CHEMISTRY
When the battery is producing an electron flow on demand or in a discharge cycle, the sulfuric acids (H3SO4) and lead (Pb) reacts to produce some Lead Sulfate (PbSO4) and some excessive hydrogen (H).  In the process free electrons are "floating" around and available at the interface of the solid lead and liquid mixture.  These excessive electrons repel each other and set up an electrical field which flows or moved along the surface of the plate, and eventually wires of the electrical system.  This flow or "pumping" of electrons can be used to turn the starter motor, honk the horn, run the lights, supply the engine electrical system, etc.  His demand for electrons put high demand on the chemistry of the battery, and remember cycle batteries are small and fragile.  

A cycle battery has a "chemical life," but it can be extended by proper care.  When a battery is not in the discharge phase or producing electron flow, there will be a chemical recharging phase, where some of the lead from PbSO4 will move back to the lead plate surface and some of the SO4, will re-bond with the free hydrogen to reform Sulfuric acid molecules.  That is where the charging system of an auto/cycle comes into play, to introduce some free electrons into the system and create enough chemical "power" to "pull" the SO4 away from the Pb.

Thus the sulfuric acid and lead if not "used" up, but it moves back and forth in a series of chemical reactions with release electrons to be used for powering the cycles electrical system, but a series of chemical reactions that to run in reverse and replenish "itself" must have "recharge" help.  That is where a Battery Tender is a must.  It "tends" to the business of keeping the correct electron flow to keep the lead in "its place" and the sulfuric acid in "its place."

SO WHAT IS THE BOTTOM LINE?
Use a Battery Tender, 100% of the time.  One Tender of each battery, hooked up whenever the bike is not being used.  Batteries self discharge sitting around and never charge properly while running, so without a Battery Tender (or similar unit) you battery is not going to be in good health.  It will be "fatigued" all the time.

Never use anything but distilled water.  Never add sulfuric acid after the initial charging.

Minimize physical "bouncing" of the battery as much as possible.

Keep the terminals very clean.  A dap of dielectric grease can help reduce problems.  Corrosion will drop you at an inopportune time.  

Buy a good brand of battery.

Do not constantly/severely discharge a battery.

Check the water level consistently.  Keep the water level up!

ALWAYS give a new battery a good charging before installation. 

SO WHAT HAPPENS TO THE LEAD, SULFURIC ACID, WATER?
As described above, the lead and acid are not used up, they just change forms.  However, during the chemical reaction going on in the battery, water vapor, free hydrogen gas, and free oxygen are lost by "evaporation" out the vent tube.  That is where the water in the battery goes.  So that is why you MUST monitor the liquid level of the battery.  Low liquid in the batter is like low liquid in you, not healthy to the system and leads to early collapse of the system if the problem continues, and even permanent damage if collected during the problem.  Check the water level often.

The lead is not used up, but there are still problems with what is called sulfacation of the plates.  Lead sulfate is a whitish crystal that adheres to the plate surface.  If allowed to build up the crystal layer will stop the chemical reactions necessary for electron flow or current to be produced.  Excessive sulfacation occurs when a battery is excessively and/or frequently discharged without being properly and consistently charged.  Again, this is where the Battery Tender comes into play.  Your battery is always kept at the right charge level, so excessive crystallization of the plate surface is delayed by a couple of years in most cases.  The life of my cycle batteries has increased a minimum of double and close to triple in most cases.  From 1-2 years per battery to 4-6 years!!

WHAT HAPPENS WHEN A BATTERY "SITS"?
An idle battery will lose about a third of its charge within a month of sitting around.  The poor chemical "health" of a partially discharged battery will drastically decrease the life expectancy. 

HEY, CAN BATTERIES BE DANGEROUS?
You bet!!  Remember that hydrogen gas and oxygen gas are produced in the chemical reaction of lead with sulfuric acid.  Remember in high science class when hydrogen gas was produced by splitting water with electricity and then collected in a test tube, and the "pop" or explosion of a glowing split when it was introduced into the test tube.

Hydrogen gas is very, very explosive and the explosion is very powerful.   Hydrogen gas burns/exploded readily.  Remember the blimp, the Hindenburg!!  Your battery can be a little Hindenburg.  It has hydrogen and oxygen gas being produced in it.  A spark can set off the hydrogen gas.  Keep sparks away from batteries.  Keep them in ventilated areas.  Hook up the charger clips before plugging into the electrical outlet.  

Wear safety goggles when working around batteries.  If acid should get into the eyes, it is imperative to flush with water as fast as possible and keep flushing for a long time, then get to a doctor quickly  to see if the cornea has been damaged, but not before extensive flushing with water.  

WHAT ABOUT A NEW BATTERY?
ALWAYS give a new battery a good charging before installation.  You can use a Battery Tender for this also.  Just hook it up and leave it on for a day.  If in a hurry, be sure to have the shop pre-charge the battery.  Do not install a battery that is not pre-charged.  A fresh battery with electrolyte has a 70-80% charge and tends never to go beyond that point without a pre-charge.

Be careful about using an excessively high or fast first charge.  Charge at a rate below 2amps, and closer to 1amp if possible.  Again, use a Battery Tender for at least 6 hours.

Interested in seeing what Tender's Old Bike Barn Carries, chick here!

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