Battery Electro Chemical Device 4 Functions - Source, Reserve & Stabilizer 1. Provides electrical energy to start car. 2. Provides electrical energy to ignition system 3. Provides electrical energy to accessories when demands exceed alternators output 4. Voltage stabilizer absorbs abnormal voltages created by electrical components
side and top post A side and top post is becoming very common today because it will fit so many cars.
Batteries a little history Up to 1955 most batteries were 6 volt General Motors started the move to 12 volts, Volkswagen was the last in 1966 to switch over. Some day cars may have a 42V/14V System. Several problems lie in wait such as cost of the components. Life of batteries & arcing between components.
Battery Construction Elements consist of two groups of plates One more negative plate than positive with insulated separators in between Usually 9, 11, or 13 plates. 54, 66, or 78 total. Case is made of hard rubber (rough service) or plastic (light service)
One element in each cell, connected to the adjoining element, connected in series, each cell produces about 2.1 volts Case is divided into 6 cells (12.6 volts) Case is divided into 4 cells (8.4 volts) Golf carts Case is divided into 3 cells (6.3 volts)
Electrolyte 64% water 36% Sulfuric acid H 2 0-water 64% specific gravity 1.00 H 2 S0 4 -sulfuric acid 36% specific gravity 1.835 - caution Electrolyte 100% specific gravity 1.270 Specific gravity is the ratio of the density of a substance to the density (mass of the same unit volume) of a reference substance. Water is the reference for specific gravity 1.00
Charged positive plate negative plate + electrolyte - H 2 S0 4 Pb0 2 Pb lead peroxideSponge lead
Discharge Oxygen and hydrogen form water, lead and sulfate form lead sulfate. It is often seen in the plates/electrodes of car batteries, as it is formed when the battery is discharged. PbSO 4 H 2 0 PbSO 4
Charging sends electrons through in the opposite way reversing the cycle Sulfated plates refer to plates harden with lead sulfate Slow long charge to correct sulfated plates sometimes it cannot reverse the affects. 2 amps 24 hours
Things to remember Little brown particles floating around can short out battery (flakes off of the sulfated plates ) Batteries can freeze if discharged H 2 O is water Charging battery emits oxygen and hydrogen gas - can explode When you need to add fluid to a battery, use distilled water (H 2 O it replaces the gas that is released H & O 2 during gassing.)
Battery Gassing nDuring discharge nDuring charge nreleases H & O 2 during gassing
Precautions When jumping a battery When using a charger When disconnecting a cable When using any flame source
Precautions Always remove ground terminal first Connect ground last – Jumper cable/battery charger on block of engine Corrosive (Sulfuric acid)
Battery types WET CHARGE shipped with electrolyte must charged during storage DRY CHARGE shipped empty with no electrolyte. Manufacture gives forming charge dries the cell elements and seals it. If you keep moisture out it will remain fully charged for long time. When needed just add electrolyte.
Group size Batteries come in many different group sizes. A battery's group size simply determines it's length, width, height, and terminal configuration Will have a number like group 75,78 or 24 or 24F, 26, 34
Battery capacity 1) Plate size, the case is the same size, plates are different size. Larger plates more amps 2) Number of plates 3) Amount of acid in electrolyte and battery additives increase the sulfuric acid content of battery.
Battery capacity rating Cold Cranking Amperes CCA most common “Number of amperes load of battery will maintain at 0 degrees Fahrenheit for 30 seconds without battery voltage falling below 7.2 volts” (1.2 volts per cell) Size of engine should be smaller than cold cranking ampere rating.
Do not be misled by CA that’s just Cranking Amps. It will give you a higher reading but it misleads you because it is tested at a higher temperature. Cranking amps are the numbers of amperes a lead-acid battery at 32 degrees F (0 degrees C) can deliver for 30 seconds and maintain at least 1.2 volts per cell (7.2 volts for a 12 volt battery).
Recommended Minimum battery size to buy when you replace it. 4-cylinder 400 CCA 6-cylinder 500 CCA 8-cylinder 575 CCA
Cracked or leaking case liquid level, add water use distilled water preferred (No minerals) or ice melted out of a freezer Voltage can discharge across top from post to post Clean battery top and post and cables, battery hold downs
Mix baking soda and water to clean batteries clean post and cable with a terminal brush or post cutter coat all connections with grease or use a spray like NOCO NCP-2 Battery corrosion spray Safety Glasses Cleaning The Battery
Battery leakage test Voltmeter (– negative) lead at negative post Voltmeter (+ positive) lead drag across battery – No voltage should be present anywhere. If it is clean the battery.
Battery Open Circuit Voltage Test Measure what the voltage is with the key off Find out it’s state of charge. It is a good starting point, should be at least 12.66 volts 12.66 = fully charged 12.4 = 3/4 charged 12.2 = 1/2 charged 12.0 = 1/4 charged
Battery Terminals & Bolts Post or top terminal Side terminal L terminal used on import Marine Stud
Terminal Test This is the first step. Take a voltmeter DVOM (Digital volt ohm meter) Turn to DC Volts Hook up like picture on next page.
Terminal Test This is just a voltage drop test done on the battery terminals. You must disable the ignition and crank over the engine. Should be under.2 volts. Make sure you do both terminals Positive & Negative
Battery Drain test or System drain test This is done When a battery goes dead for no apparent reason. Charging system seems to work OK Yet after charging the battery it is dead after several nights.
Battery Drain test or System drain test everything off Make sure you close the door or the courtesy lights will be on Ammeter is hooked in series at the battery post with everything off Make sure you close the door or the courtesy lights will be on
Battery Drain test Make sure you change the leads
Battery Drain test Battery Drain Key off Hook up a ammeter in series reading should not exceed the following 77 older cars.01 amps, 10 ma (milliamps) 78-85.02 amps-.025 amps, 20-25 ma 1986 & newer.05 amps, 50 ma
Open Circuit Voltage Test Sealed batteries Remove surface charge Remove surface charge 12.66 = fully charged 12.4 = 3/4 charged Battery Voltage with the car off.
Must be 3/4 charged before doing a battery capacity test A battery Must be 3/4 charged before doing a battery capacity test
Check the temp. Before load testing - Check the temp.
Before load testing you must know what the battery is, or should be rated at The right battery for the vehicle
Ratings Cold cranking Amperes rating CCA Cranking Amperes rating CA Ampere-hour rating Reserve capacity rating Watt hour rating
P - L130 Capacity Test Three times the ampere-hour rating Formula for load testing
Cold cranking amps divided by 2 Formula for load testing
Three minute charge test sulfated Tests for a sulfated battery 40 amps for three minutes below Should be below 15.5 volts
Testing specific gravity Hydrometer check before adding water fully charged battery should read 1.270 should not vary more than 50 points between cells if it does recharge and check again Maintenance free batteries are sealed, cannot get into some. No way to add water or check specific gravity.
Charging batteries Clean up Battery first Unhook cables - check liquid level Don't charge over 16 volts. If plates are sulfated or if battery has been discharged for some time Slow charge for a long period 24 hours don't allow temperature to exceed 100 Never fast charge batteries Make sure that the battery charger is shut off or unplugged when hooking up and removing the charger.
Did You Know Batteries Lose Power While Sitting on the Shelf? A battery can permanently lose some of its capacity when it's stored in a partly or fully discharged state. Periodic charging during storage can minimize the deterioration, but not all battery distributors and dealers do the necessary charging. That's why you may want to know how to read the date codes, which show when the product was manufactured, on a new product, to help you make sure you're really buying a fresh battery. So, how do you read a date code?
Most Brands of Batteries JOHNSON CONTROLS, INC. - INTERSTATE BATTERIES, Motorcraft, East penn - Deka, GNB -Champion, Stowaway: The letters and numbers are on a sticker affixed to the battery or hot-stamped into the case cover along the top edges of the battery. The ship date codes begin with a letter: A stands for January, B for February and so on (some shipping codes skip the letter I, so it cannot be confused with the number 1. In those cases, J would represent September, K - October, L - November and M - December). The next digit is a number which represents the year the battery was shipped. Therefore, an A6 would mean the battery was shipped in January of 1996.
Always Disconnect the ground cable first. (Negative Cable on cars) Always hook up the ground cable last If you disconnect the positive first and touch ground you will have sparks. Removing Batteries
Always make sure you have a way to keep the memory alive (Computer, radio, etc) when you replace the battery. Removing Batteries