Rider EducationBy Robin Koontz I donít think Iíve ever talked about batteries in any detail. So, Iíll pull out the manual I got from a Yuasa representative that I got at a Safety Sunday a couple of years ago and dig out some juicy stuff.
A battery is an electrochemical device that converts chemical energy to electrical energy. A battery has a number of cells, and each cell has about two volts (actually, 2.12 to 2.2 volts, measured on a direct current scale). A 6-volt battery has three cells, a 12-volt has six cells. The cells have lead plates that are positive and negative charged. Inside the cell theyíre stacked alternately - negative, positive, negative, and so on. Insulators or separators, usually fiberglass or treated paper, are placed between the plates to prevent contact. Cranking current increases as the plate surface area in the battery increases - the more plates in a cell, or the larger the plates, the greater the current capacity (or flow of electricity).
A solution of sulfuric acid and distilled water - the electrolyte - is added. This starts the action. A reaction between the lead plates and the electrolyte sets off a chemical change. This in turn creates the electrical charge in a battery.
Safety points about handling and working around batteries are:
- ABSOLUTELY NO SMOKING, SPARKS, OR FLAMES AROUND A CHARGING BATTERY. Charging gives off hydrogen and oxygen, which explode if ignited (think Hindenburg).
- Loosen vent caps on a conventional battery when charging, and ventilate area - explosion hazard due to hydrogen and oxygen buildup.
- If battery feels hot to the touch during charging, stop charging and allow to cool before resuming. Heat damages plates, and a hot battery can explode.
- NEVER put the red sealing cap back on the battery once you take it off. If you do, gases trapped inside can explode.
- Make sure vent tube isnít kinked or blocked, for the same reason.
- Make sure charger or bike wires are connected pos to pos, neg to neg. unplug charger before connecting or unconnecting leads to cut down chance of sparks.
- Always wear a face shield or safety goggles - acid in the eyes is serious. And wear plastic gloves to prevent acid burns. Keep is off clothing to prevent the Ďholeyí look.
- Clean up acid spills immediately, using a water and baking soda solution to neutralize (one pound baking soda in one gallon water).
- If acid is splashed on skin, flush with lots of water. If ingested, drink large quantities of milk or water, followed by milk of magnesia, vegetable oil, or beaten eggs. Call a poison control center or doctor immediately. If splashed in eyes, flush for several minutes with water and get immediate medical attention to prevent blindness.
Now that I have covered the different parts of a battery, how it makes power for your bike, and some important safety precautions to take around this powerful device, Iíll go over how to charge your brand-new battery the way the manufacturer (Yuasa in this case) wants you to.
Sealed at the factory, a new battery has an indefinite shelf life as long as it remains sealed and the red cap covering the vent tube remains in place, and is stored at room temperature. Once it is unsealed, a battery should be activated, charged, and installed. Whyís that? The plates of an unsealed, uncharged battery begin to oxidize, and that makes it harder to charge later. And if it is charged and sits around, it starts to discharge and sulfate; how fast depends on temperature.
Hereís how to activate most batteries (maintenance-free batteries are activated differently):
1. First buy the thing. Make sure the red vent cap is still intact. Take it home still in the box, untouched by the shopís charger. Remove the filling plugs on the top of the battery, and also remove the red vent cap. Throw the red cap away...putting it back on a battery filled with acid can cause an explosion.
2. Place battery on level surface. Fill battery with electrolyte (a sulfuric acid dilution with a specific gravity of 1.265) provided with the new battery. Do not use water or any other liquid to activate. Electrolyte should be between 60E and 86EF before filling. Fill to UPPER LEVEL as indicated on battery.
3. Let battery stand for at least 30 minutes, but no more than about an hour. Move or gently tap the battery so that any air bubbles between the plates will be expelled. If acid level has fallen, refill to upper level with more acid. THIS IS THE ONLY TIME YOU CAN ADD MORE ACID. After this step, you can only add distilled water.
4. A battery must be completely charged before installation. Charge for three to five hours at the current equivalent of 1/10th of its rated capacity found in the Yuasa Applications book. (If you have a different brand battery, use itís table, which will be included in the box.) It should be anywhere from 9 to 12, as found in the column marked CAPACITY AH (10H-R).
5. During charging, batteries can spit electrolyte out the open vent. Take care to loosely refit fill plugs, on top).
6. Check during charging to see if electrolyte level has fallen, and if so, fill with distilled or clean water to the UPPER LEVEL. After adding water, charge for another hour at the same rate as above to mix the water and acid.
7. When chargingís done, replace plugs firmly. Do not apply excessive pressure nor over-tighten.
8. Wash off spilled acid with water and baking soda solution, paying particular attention that any acid is washed off the terminals. Dry the battery case.
Hereís what not to do:
1. Throw a new battery into a bike and ride off without charging. "The bike will charge it," they figure. Wrong. A battery out of the box, with electrolyte added but uncharged, is at 80% capacity tops. And it will never hold more than that 80% charge if not charged correctly first before using. The bike will not charge it more. Nor will throwing it on a charger later. Itís capacity has been immediately and permanently cut by 20%, and thereís not a thing you can do about it. Insist on that initial booster charge before riding.
2. Quick charge it. This is what you get from the motorcycle shop when it takes only an hour to ram-charge your battery to readiness. What happens is that only the surface area of the plates can be quick charged. A lower current for a longer time charges the battery more uniformly. That means better performance. Also, charging rates above 2 or 2.5 amperes increase the chance of overheating, which can cause battery damage.
Robin Koontz, Chapter Educator
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