THE STORY OF THE MODERN STORAGE BATTERY

[Music] [Music] the modern storage battery is a concentrated source of electricity that symbolizes man's efforts to better his life through the control of nature's power resources here is a means of storing energy and using it when we want it the automobile storage battery supplies the electrical energy to start the car engine and give standby power to operate the lights the radio and the other electrical accessories of the automobile fuel storage batteries are part of the power plans of the atomic submarine [Music] small storage batteries help control giant guided missiles [Music] storage batteries power ocean boys to help guide Mariners in dangerous waters in hospitals and in public buildings storage batteries supplies standby emergency power there are many different kinds of batteries doing many different kinds of jobs yet the principle upon which these storage batteries work is the same what is this principle a storage battery is an electrochemical device for storing energy and chemical form so that it can be released as electricity now the principle of operation is simply this - unlike metals when immersed in an acid solution create a chemical reaction one product of this reaction is released electrons that make up an electrical current the two unlike metals could be copper and silver for example Oh as for the acid solution here's one source the citric acid in an ordinary grape immersing this quarter miss penny and the grapefruit has created the battery desert areas here actually is a source of electricity as current though very small can be measured so you see this is a battery currently produces enough electrical current for any useful purpose nevertheless these two batteries operate on the same basic principle the two unlike metals may be copper and sake these are immersed in dilute sulfuric acid a much better electrolyte than the citric acid of a grapefruit again the resulting chemical reaction produces electricity this is a stronger battery approximately one volt yes - unlike metals immersed in an acid solution will produce a measurable electrical current the discovery of this principle goes back more than 150 years to the famous Italian nobleman Alessandro Volta often called the father of modern electrical science in 1800 he invented the voltaic pile the first electric battery this consisted of a series of disks zinc silver and cloth soaked in the electrolyte which was bright more disks the higher the voltage and some of these early voltaic piles were more than 6 feet long this primitive battery opened up a vast area of experimentation and research but it had very marked limitations first of all its power output was low and the metals used silver and zinc wore out too quickly as in our experimental cell after a short time the zinc plate as you can see is almost consumed by the electrolyte you can't charge a battery like this because it's a primary battery it be discharged only once and then its usefulness is ended this is the principle of the flashlight cell but the storage battery needs plates that will stand up for a long time and can be discharged and charged again and again the answer is the lead plate first developed by the french scientist gaston Plantae in 1859 these LED plates when immersed in our electrolyte solution make up what is called a secondary or more popularly a storage battery it can be charged and discharged over and over again why because lead is not consumed when immersed in an electrolyte of sulfuric acid and water but there is no chemical reaction going on here remember these plates are led both of the same metal and it takes two unlike metals in the electrolyte to make electricity so what do we do we change these plates to make them act like unlike metals by charging them the battery is now being charged are we storing electricity in the battery no actually we're making chemical changes in the place so that they can produce electricity the current from the battery charger is convert plates of like metal into plates of unlike metallic compounds several hours are required for the charging when the charge is completed these plates are no longer alight now what has happened this plate has become the positive plate it's color has changed from grey to dark brown because a chemical reaction has taken place which the LED on the surface of the plate has changed to lead dioxide usually called lead peroxide in the battery industry this plate has become the negative plate it is still led as it was before charging so now we have to unlike forms of the same metal lead and lead peroxide in the storage battery these will work in the same way has to completely unlike metals the voltage of this battery measures approximately 2 volts a battery with plates of this kind can be charged and discharged over and over again remember a storage battery does not store electricity it just appears to do so actually a storage battery stores energy and chemical form which it releases as electricity and it can do it repeatedly let's look at a schematic diagram of the chemical reaction that releases this electrical current in this beaker we have the electrolyte dilute sulfuric acid here is the positive plate of the battery lead peroxide here is the negative plate of the battery plain metallic layer now let's consume the electrical energy this battery creates by placing a light bulb in the circuit when the switch is closed the circuit is completed the current flows and the light bulb lights up remember the battery supply of this electrical current through a chemical reaction and during this process it is being discharged as long as we are watching a chemical reaction let's refer to these materials by their chemical names Bibi means lit but PBO two means one atom of lead and two atoms of oxygen and that makes lead peroxide h2so4 means two atoms of hydrogen one atom of sulfur and four atoms of oxygen and that makes sulfuric acid h2o means two atoms of hydrogen and one of oxygen and that makes water and pbso4 means one atom of lead one atom of sulfur and four atoms of oxygen and that makes lead sulfate when the battery is discharging an electrochemical reaction is taking place as soon as the switch is closed the two atoms of oxygen in the PBO to break away to seek some other chemical with which to combine at the same time the so4 of the electrolyte combines with the chemicals in the plates to form pbso4 lead sulfate in the meantime the two atoms of oxygen the o2 separate each combining with an h2 two atoms of hydrogen to form h2o which we all recognize as the symbol for water as this chemical reaction takes place electrons are released these make up the energy that gives us our electrical current that's all there is to it the battery is discharged and the lamp goes out we now have two like metallic compounds both plates are pbso4 lead sulfate what's more they're immersed not in an acid solution but in h2o plain water and light metals in plain water do not produce an electrochemical reaction this is what happens when we discharge a battery now what happens when we charge it let's put a battery charger into the circuit instead of this light bulb electrons are returned to our cell and the reverse of the discharging electrochemical reaction takes place the oxygen atoms of the water break away and form o to the s o force break free from the plates and reunite with the h2s to form the electrolyte sulfuric acid while all this is going on the o2 s returned to the positive plate to form PB o to again lead peroxide the negative plate becomes PB layer now notice the plates again act as unlike metals immersed in an acid solution our battery has been recharged this is what happens in the storage battery behind this development is the work of men like Charles brush and ta Willard although the electrochemical principles are the same for both of these batteries there are many many differences let's look at these differences for a moment here is a small and compact version of a modern storage battery much smaller than an automotive battery but it is almost identical in construction and operation now what is the difference between this battery and this battery this experimental cell is hardly more than a Laboratory Curiosity if you tip it it's pills turn it upside down and it literally falls apart but this modern battery is a compact sealed package it's practical and durable will operate in any position on its side or end even upside down and its leak proof these are obvious physical characteristics now watch the difference in electrical characteristics here we have two ordinary 6 volt fog lights one I'll light up with our experimental cells hooked up in series this one I'll connect to this modern 3 cell 6 volt battery even while I'm talking about it the light connected to the experimental battery is beginning to dim out in less than half a minute it will be out the light connected to the modern battery burns brightly and will continue to do so for a half hour or more why does this modern battery gives so much more electrical current what makes the difference the main difference is in the plates there are only two plates in each cell of this experimental battery against nine plates in each cell of this modern battery for positive and five negative plates each plate contains many times more active material than does the experimental plate this plate from the experimental battery is only a thin coating of lead peroxide the active material in the positive plates if you scrape off all the active material it doesn't make a very big pile the modern plate starts with a lead casting or grid as it is called the ingredients that make up the active material are mixed together to form a stiff paste which is applied to the grid filling every open space when the active material dries and hardens it becomes extremely porous permitting deep penetration by the electrolyte consequently producing more electrochemical reaction this is true of both positive and negative plates after drying and hardening the plate is charged the charge plate is more than 50% active material with so much more active material it's no wonder that the modern plate delivers so much more electrical current of course the larger the battery the larger the grid this is a grid for an automotive battery you'll notice that the horizontal grid bars are triangular in cross-section to seal all the active material firmly into place precision design and construction details like this and many of them are incorporated in today's battery are not readily apparent to casual observation but they are important to remember this modern battery employs the same principle as the first battery ever built too unlike metals in electrolyte create a chemical reaction that produces electricity much experimentation and research has brought the battery from this simple beginning to the modern storage battery we use today yet research still goes on scientists engineers and technicians are working to make batteries smaller and even more powerful they are developing batteries to work under the most adverse conditions they are developing new principles of design and operation through the tools of modern science such research is also directed towards the discovery of new materials and better manufacturing methods modern mass production of batteries starts with the grid LED alloyed with other metals goes into automatic molding machines to make the grids [Music] the grits are cast in pairs for easier handling [Music] meanwhile the active material is being prepared chemically pure LED is converted to lead oxide and ground to a precise texture that assures maximum penetration by the electrolyte [Music] this led oxide is mixed into a paste that is carefully compounded to retain the highly porous characteristics and permitted to be applied evenly and compactly into each grid cavity in a fully automatic pasting operation as the pasted grids now called plates move away from the pasting machine they undergo controlled heat treatment that removes excess moisture some of these plates will be charged and used for making what is known as the dry charged battery the remainder will be used as they are for making wet charged batteries other parts of the battery are made with equal precision and care automatic rotary casting machines turnout cell connectors plate connectors and other metal parts to fit batteries of all sizes and shapes [Music] not only are the battery components inspected by the workers on the production line but samples of finished components are laboratory checked on a continuing schedule the first step in assembling the battery is making the element the negative plates separators and positive plates are alternated and positioned in exact numbers the separators prevent the negative and positive plates from touching a condition which would short-circuit a battery [Music] welding or burning as it is called by battery men connects the plates into groups which along with the separators make up what is called an element 1 element is used in each cell of a battery the six elements of the 12-volt automobile battery are inserted in the rubber case and then tested to make certain that assembly and welding are correct the batteries move on four cell covers cell connectors battery post molding and connector burning then comes double ceiling with a special compound that withstands the heat of summer and the cold of winter for wet charged batteries the electrolyte is added at the factory the battery is charged ready for installation in an automobile without further preparation for dry charged batteries the electrolyte is added by the dealer when the battery is placed in service wet or dry charge the modern storage battery is manufactured to exacting specifications to assure long life and dependable performance batteries taken right from stock are spot tested under conditions far more grueling than ever encountered by a motorist they're tested on special apparatus that measures battery life and consistency of operation under extremes of temperature colder than the Antarctic far hotter than the tropics the modern battery starts out with every advantage that built-in quality can give it but in an automobile the battery is not a completely independent unit [Music] honey I can't get the car started what's the matter with it well I don't know it just won't start well maybe it's the battery the battery I don't know I thought he just won't start don't worry call it a service station and have them take care of I don't see why I should need a new battery while you're all battery I'm afraid is ruined won't even hold a charge I don't know why I thought a battery is supposed to last longer than a year ordinarily Gil it should so why didn't mine stand up well there are a lot of possible reasons out maybe here in your car's electrical system and your battery of course operates in conjunction with the other electrical units in your car it could have been caused by worn insulation in the wiring or by an improperly adjusted voltage and current regulator or by the stop light switch by a faulty starter that can be caused by a faulty generator by corroded battery cables or by a short-circuit anywhere in the electrical system the lights the accessories any of these things any little electrical leaf can run a battery down if the cars out of use for four or five days and of course it's possible to abuse a battery without realizing it here look at this loose hold downs in the battery carrier caused damage to this battery when a battery bounces and shakes in the carrier the case may be damaged and the battery posts can be broken or a battery can be dry such as yours was now I've added water and tried to charge it but it just won't charge see now this is your bad self after a battery has been dry too long this is what's likely to happen to the plates above this line the plate has been dry overheated and probably ruined now here's what a good plate looks like here's a plate from a battery that was allowed to remain in the discharged condition these hard insoluble sulphate crystals on the plates usually mean that the battery is ruined it can happen to new batteries as well as to old ones now here's a plate from a battery that was overcharged in the owners car overcharging causes the plates to disintegrate this one is completely ruined a battery in good condition is important to you it means quick starting which conserves gas and also conserves the life of your car engine what's more quick starting conserves the life of your battery - ok I guess I better have a new battery do I get a credit allowance on the old one most certainly do your old batteries worth money what do you do with the old battery junket there's a lot of less than that old battery it'll be refined and used over again I understand they tell me that about 1/4 of all the lead used in this country every year comes from the LED that salvaged from these old batteries here's the battery for your Cargill [Music] that's the story of the modern storage battery a concentrated package of power that works for us in dozens of ways every day transportation and communication in science and in industry yes the storage battery is at work forests in many ways the story of the storage battery began more than 150 years ago with the voltaic pile this story will go on and on as the storage battery does more and more force helping us in our never-ending search for improved sources of energy to make our standard of living a better [Music]