battery – Battery Education

What Raw Minerals Are Used To Make a Battery?

To build a battery you have four basic overarching battery components including the casing, chemistry, electrolyte, and the internal specialized hardware. At the core of these four basic overarching battery components are the foundation blocks; the raw materials necessary for the construction of a battery. Minerals and materials used in the construction of batteries are numerous but the core mineral required to have a battery is the batteries chemical which can either be : cadmium, cobalt, lead, lithium, and nickel (along with other rare earth elements). Why is the chemical one of the most important element in a battery: because a battery at its most basic element is a system that converts and stores electrochemical energy for the purpose of providing portable power to a device. Without the chemistry changing chemical energy into electrical energy is impossible. So needless to say the availability of minerals used in batteries are highly important!

Incidentally the available raw material supply and price often times dictates how much your battery is going to be – if the raw material price is higher, than, your battery cost will be higher (the converse of that is also true). But what are the current supplies of the battery making minerals and how much demand is out there for these minerals?

In the United States there are currently 6,841 different mining operations ranging from aluminum to zircon. Although 6,841 mines sounds like a lot of mining operations you must evaluate that number against the total demand of minerals. Consider that every American born in 2007 is estimated to use the following amounts of nonfuel mineral commodities over their lifetime (data pulled from MII):

Aluminum (bauxite) 5,677 pounds
Cement 65,480 pounds
Clays 19,245 pounds
Copper 1,309 pounds
Gold 1,576 ounces
Iron ore 29,608 pounds
Lead 928 pounds
Phosphate rock 19,815 pounds
Stone, sand, and gravel 1.61 million pounds
Zinc 671 pounds

Now consider that there were 4,315,000 babies born in 2007 (U.S. Census Bureau). So when you start multiplying the amounts of estimated use of each of the minerals you can quickly see 6,841 mines is not really a whole lot!

Lithium, Cadmium, Cobalt, Nickel By The Numbers

Chile was the leading lithium chemical producer in the world with Argentina, China, and the United States as additional major producers. The United States remained the leading consumer of lithium minerals and compounds and the leading producer of value-added lithium materials. Incidentally only one company produced lithium compounds in the U.S. and that is at the Silver Peak Mine in Nevada run by the Chemetall Foote Corporation. Lithium is used not only in batteries but also in ceramics and glass, lubricating greases, pharmaceuticals and polymers, air conditioning, primary aluminum production, continuous casting, chemical processing and other uses. In terms of annual quantity of lithium the USGS estimates that in the U.S in 2005 5,000,000 pounds of lithium was used in rechargeable batteries.

In terms of annual quantity of cadmium the USGS estimates that in the U.S in 2005 1,312,000 pounds of cadmium was used in rechargeable batteries.

In terms of annual quantity of cobalt (cobalt is used primarily for the battery’s electrodes) the USGS estimates that in the U.S in 2005 23,800,000 pounds of cobalt was used in rechargeable batteries.

In terms of annual quantity of nickel the USGS estimates that in the U.S in 2005 426,000,000 pounds of nickel was used in rechargeable batteries.

How Much Demand is there for these Minerals?

In 2002 it is estimated that 350 million batteries were purchased in the U.S. So if you assume that the past 7 years have been fairly consistent then you could assume that 2.4 Billion batteries were bought and in use and will eventually need to be recycled and replaced. This means that an ever increasing demand for minerals will be placed on the mines of the earth.

Thankfully there is enough available minerals and metals to be extracted from mines that at least for the time being we do not have to be overly concerned, but, indeed there will come a point decades down the road, that this will not always be true.

Until next time, Dan Hagopian – www.batteryship.com
Copyright © BatteryEducation.com. All rights reserved.

How Long Will My Battery Last?

Most rechargeable batteries have a charge-discharge cycle that ranges between 300-500 cycles (for lithium based chemistries – NIMH can have up to 800 charge-discharge cycles and NICD chemistries can have up to 1200). A charge-discharge cycle means that a battery once at 100% draws power down to 0%. Then after recharge it will be back at 100%. This can be done 300-500 times on the same lithium based battery. Now most battery users recharge their batteries before the battery reaches 0%, this is perfectly acceptable, but still the same principles of the charge-discharge cycle limitations are in effect.

One common mistake is to assume that a battery that has a 1 year warranty will last for 365 days and when it does not last 1 year the assumption is is that the battery must be bad. This is a fallacy and an erroneous belief – in essence incorrect!

Here is why!

As I have written in other articles a battery is a device that converts chemical energy into electrical energy. Batteries have two electrodes, an anode (the negative end) and a cathode (the positive end). Collectively the anode and the cathode are called the electrodes. In between the battery’s two electrodes runs an electrical current caused primarily from a voltage differential between the anode and cathode. The voltage runs through a chemical called an electrolyte (which can be either be in a liquid, solid, or gel state). This battery consisting of two electrodes is called a voltaic cell. Most batteries today are advance forms of the voltaic cells and have additional technology packed into the battery casing to support the overall system and its connected device. These controls include the connector, fuse, charge and discharge FETs, the cell pack, the sense resistor (RSENSE), the primary and secondary protection ICs, the fuel-gauge IC thermistor, pc board, and the EEPROM or firmware for the fuel-gauge IC.

How Does a Battery Work and What Does It Produce?

We know that the result of a battery converting chemical energy into electrical energy allows us to turn on our laptop, PDA, MP3 or even a cell-phone. But how does the conversion process take place? As stated above the batteries we use today are variable changes of the voltaic pile. In addition to the controls I listed above today’s batteries are made up of plates of reactive chemicals (Li-ion, Li-po, NIMH, NICD) separated by an electrolyte barrier (which can be either be in a liquid, solid, or gel state), and subsequently polarized so all the electrons gather on one side. The system was designed to separate both positive and negative electrons. Then after separation an electron exchange occurs and a current of electron flow moves electrons to and from the anode and cathode. Simultaneously an electrochemical reaction takes place inside the battery to replenish the electrons. The effect is a chemical process that creates electrochemical energy.

Now the electrochemical reaction that is taking place is a chemical change that is necessary in order to create electricity. One factor that needs to be understood is that electricity is the flow of electrons. Specifically, electricity is a property of subatomic particles which couples to electromagnetic fields and causes attractive and repulsive forces between them. This repulsive force between the subatomic particles creates an electric current; the flow of electric charge transports energy from one atom to another. This electrical current is measured in amperes, where 1 ampere is the flow of 62,000,000,000,000,000,000 electrons per second!

Electricity therefore is a created energy source. All electricity in fact is a created source made or converted from coal, natural gas, oil, nuclear power, wind, heat, sun, water, biomass and or other chemicals. In batteries today electricity is created by two chemicals in a solution for example: {a Solution of Lithium hexaflourophosphate (LiPF6) – a mixture of Organic Solvents: [Ethylene Carbonate (EC) + DiEthyl Carbonate (DMC) + DiEthyl Carbonate (DEC) + Ethyl Acetate (EA)]}

To create electricity within a battery first and foremost the battery's chemistry must be charged. Charging lithium can be thought of as the introduction of ions or movement of chemistry. To move the lithium chemistry (lithium-ion, lithium polymer, lithium iron phosphate, etc) you have to have a minimum voltage applied to the lithium. Most battery cells are charged to 4.2 volts with relative safe workings at about 3.8 volts. Anything less than 3.3 volts will not be enough to charge or move the chemistry. One thing to note here is that volts are an algorithmic measurement of current. So in a sense to create current through your battery you have to introduce current into your battery’s lithium .

Introducing current into your lithium is called intercalation. Intercalation is the joining of a molecule (or molecule group) between two other molecules (or groups). When it comes to charging your battery you are in effect pushing ions in and out of solid lithium compounds. These compounds have minuscule spaces between the crystallized planes for small ions, such as lithium, to insert themselves from a force of current. In effect ionizing the lithium loads the crystal planes to the point where they are forced into a current flow. The current flow is then channeled back and forth from anode to cathode and thereby creating an electrical flow to power on your device. Again this can done 300-500 times before all the ions are pushed out of the lithium and you will no longer be able to charge your device.

One final thought and that is runtime (time between charges). After each charge-discharge cycle the runtime (time between charges) is reduced by intercalation as discussed above. For example you may notice in the first 3-4 months you are getting between 3-5 hours of runtime on your battery. Then in months 5-12 (after your purchase) you notice that you are slowly getting less and less runtime in between charges until you might be getting less than 5 minutes of runtime. This is the normal use of the chemistry inside your battery and DOES NOT mean that the battery is bad, but simply has been used by you.

Until next time – Dan Hagopian, www.BatteryShip.com
Copyright © BatteryEducation.com. All rights reserved.

How Green Are Batteries?

When you peer into the world of batteries your first thought is “wow – there sure are a lot of batteries”. While this is certainly true as self directed environmentalist I wonder just how many batteries can actually be recycled. To answer the question let’s look at batteries from the manufacturing floor on up to the end user.

The battery business just as in any business requires that materials are bought, assembled into products, and eventually sold to an end user. Batteries however have an interesting collection of materials, which are designed to collect energy, store energy, and redistribute energy on demand. These processes on the surface seem very environmentally friendly but let’s see just how friendly!

As alluded to above building a battery requires basic components including: the casing, the chemistry, the electrolyte, and the battery’s specialized hardware

The Battery Casing

The purpose of a battery casing is for enclosing and hermetically sealing an internal battery body. Battery casings are manufactured in layers. The casing layers are developed from various raw materials and can include one or two polyethylene terephthalate layers (a thermoplastic polymer resin of the polyester family), a polymer layer, and a polypropylene layer (another thermoplastic polymer). The entire casing can be recycled.

The Battery Chemistry

As noted above a battery is a device that converts chemical energy into electrical energy. To convert chemical energy into electrical energy the battery must contain the chemical base to allow conversion to occur. Types of common chemicals used in batteries on the market today are:

• Lithium Ion (Li-ion)
• Lithium Polymer (Li-po)
• Lithium-thionyl chloride (Li-SOCl₂)
• Lithium-sulfur dioxide (Li-SO₂)
• Lithium-manganese dioxide (Li-MnO₂)
• Nickel-cadmium (NICD)
• Nickel-metal-hydride (NIMH)
• Lead-acid batteries
• Reusable Alkaline

Each of these chemistries can be recycled.

The Battery’s Electrolyte

The actual conversion of chemical energy into electrochemical energy can only be done if an electron flow passes between two electrodes, an anode (the negative end) and a cathode (the positive end). The battery’s electrical current (electron flow) runs from one electrode to another through a conductive chemical called an electrolyte solution.

A basic electrolyte solution is a chemical compound (salt, acid, or base) that when dissolved in a solvent forms a solution that becomes an ionic conductor of electricity. In the battery cell the electrolyte solution is the conducting medium in which the flow of electric current between the electrodes takes place by the migrating electrons.

At the end of the battery’s electrolyte solution’s life, the spent battery acid can be neutralized using an industrial grade baking soda compound. After neutralization the acid turns into water, treated, cleaned to meet clean water standards, and then released into the public sewer system. Another option would be to convert spent battery acid into sodium sulfate, which is used in laundry detergent, glass and textile manufacturing.

The Battery’s Specialized Hardware

A battery consists of more than the casing, electrolyte, and the chemical. It requires some very specialized hardware, especially when we speak directly about a smart battery. Your typical smart battery may have a multitude of hardware components that when working in tandem not merely create electrical power and transfer it to a particular device but additionally sends data packets of information to the device so that the device can actually gauge the battery (at least in theory). Some of the common hardware features in a smart battery include: the connector, the fuse, the charge and discharge FETs, the cell pack, the sense resistor (RSENSE), the primary and secondary protection ICs, the fuel-gauge IC, the thermistor, the pc board, and the EEPROM or firmware for the fuel-gauge IC. The materials that comprise these individual components can be broken down and recycled.

So How Green Are Batteries?

Batteries are very environmentally safe, especially batteries that are rechargeable.

Until next time – Dan Hagopian, www.BatteryShip.com
Copyright © BatteryEducation.com. All rights reserved.

Rechargeable Batteries Can Only Be Charged 300-500 Times – Part 2

In the last two articles we addressed how and why rechargeable batteries have limited charge cycles. We reviewed in detail the effect of a charge-discharge cycle – a chemical change in a battery system that results in degradation and power loss. But there is one aspect in my last article that deserves special attention. This one factor is the basis of battery degradation. It is the reason why batteries can never just keep going and going and going. The fact is, is that all batteries degrade and lose power because there is a reduction in the battery’s active material.

We know that a battery is a device that converts chemical energy into electrical energy. In order to convert chemical energy into electrical energy there is a chain of events that have to occur prior to the creation of electrical energy. The chain of events have been discussed in depth in previous articles which you can access on my blog but what is key to the creation of electricity is that in batteries electrical energy is produced from two chemicals in a solution. After discharging you recharge the battery via a charger. The charge process involves intercalation: the joining of a molecule (or molecule group) between two other molecules (or groups). Intercalation is the process of ions being pushed by electrical current into solid lithium compounds. Lithium is one of the chemical components used to create electrical energy in batteries. Lithium compounds have minuscule spaces between the crystallized planes for small ions to insert themselves from a force of current. Ionizing lithium loads the crystal planes to the point where they are forced into a current flow. Intercalation replenishes, in effect, lithium but the net result of ionization is the ultimate depletion of the lithium reactive property. You could say if you use it you will lose it!

Why then is lithium used as the chemical to create electricity in batteries? There are a number of good reasons – let’s look at a few!

General Characteristics of Lithium

Name: lithium
Symbol: Li
Atomic number: 3
Atomic weight: [6.941 (2)] g m r
CAS Registry ID: 7439-93-2
Group number: 1
Group name: Alkali metal
Period number: 2
Block: s-block
Standard state: solid at 298 K
Color: silvery white/grey
Classification: Metallic

Lithium is one of the metals in the alkali group (the other metals include Sodium, Potassium, Rubidium, Cesium, and Francium). Lithium is a highly reactive metal. Lithium has only one electron in its outer shell (two electrons in its inner shell), which makes it chemically “ready” to lose that one electron in ionic bonding with other elements. Lithium is used as a battery anode material (due to its high electrochemical potential). Electrochemical potential is the sum of the chemical potential and the electrical potential. The higher the electrochemical potential the better the electrical current yields. In some lithium-based cells the electrochemical potential can be five times greater than an equivalent-sized lead-acid cell and three times greater than alkaline batteries. One other core advantage that lithium has is that it is soft and bendable which allows for tight configurations in small cell designs (PDAs. Laptops, Cameras etc…).

Lithium, even with all of its good chemical properties will eventually, however, react to the point where the electrochemical potential will yield a charge that is simply not enough to create current to pass to power a device.

Until next time Dan Hagopian www.batteryship.com
Copyright © BatteryEducation.com. All rights reserved.

Rechargeable Batteries Can Only Be Charged 300-500 Times – Part 1

A charge-discharge cycle involves draining or using your battery to where there is for all intensive purposes, no charge left, and then subsequently charging the battery with a power adapter to 100% capacity. This process of charging and discharging (charge cycling) can only be done between 300-500 times. The question that we want to address is why? Why is it that lithium batteries can only be charged less than 500 times? Why does a battery over time degrade and eventually stops working and what if any does the reduction of the battery's active material and subsequent causes of chemical changes effect battery degredation?

In my last article I explained how that the simple task of charging a battery is far from easy. For example I examined how a battery, a device that converts chemical energy into electrical energy, has two internal electrodes – an anode (the negative end) and a cathode (the positive end), and that between the two electrodes runs an electrical current caused primarily from a voltage differential between the anode and cathode. We learned that batteries are made up of plates of reactive chemicals (Li-ion, Li-po, NIMH, NICD) separated by an electrolyte barrier (which can be either be in a liquid, solid, or gel state), and subsequently polarized so all the electrons gather on one side. We looked at how electricity is produced through a chemical change inside the battery system. We also learned that batteries require electricity to produce electricity and that the introduction of electricity involves replenishing the electrons in the lithium chemical and this chemical process is called intercalation, which, is the joining of a molecule between two other molecules. So without question charging a battery is anything but easy.

One other thing we learned that has helped shape this article is that a charge-discharge cycle involves draining or using your battery to where there is for all intensive purposes, no charge left, and then subsequently charging the battery with a power adapter to 100% capacity. This process of charging and discharging (charge cycling) can only be done between 300-500 times. The question that we want to address is why is it that lithium batteries can only be charged less than 500 times?

Battery Degradation and Power Loss

A battery over time degrades and eventually stops working, this is no surprise, but why this occurs is really a fascinating yet technical process. These reasons are complex issues that are way beyond user control and are wholly contained within your battery and within your device! These technical processes are a result of the reduction of the battery’s active material and subsequent causes of chemical changes. The chemical changes that I write of are:

Declining capacity – when the amount of charge a battery can hold gradually decreases due to usage, aging, and with some chemistry, lack of maintenance.

The loss of charge acceptance of the Li‑ion/polymer batteries is due to cell oxidation. Cell oxidation is when the cells of the battery lose their electrons. This is a normal process of the battery discharge process. In fact every time you use your battery a loss of charge acceptance occurs (the charge loss allows your battery to power your device by delivering electrical current to your device). Capacity loss is permanent. Li‑ion/polymer batteries cannot be restored with cycling or any other external means. The capacity loss is permanent because the metals used in the cells run for a specific time only and are being consumed during their service life.

Internal resistance, known as impedance, determines the performance and runtime of a battery. It is a measure of opposition to a sinusoidal electric current. A high internal resistance curtails the flow of energy from the battery to a device. The aging of the battery cells contributes, primarily, to the increase in resistance, not usage. The internal resistance of the Li‑ion batteries cannot be improved with cycling (recharging). Cell oxidation, which causes high resistance, is non-reversible and is the ultimate cause of battery failure (energy may still be present in the battery, but it can no longer be delivered due to poor conductivity).

All batteries have an inherent elevated self-discharge. The self-discharge on nickel-based batteries is 10 to 15 percent of its capacity in the first 24 hours after charge, followed by 10 to 15 percent every month thereafter. Li‑ion battery's self-discharges about five percent in the first 24 hours and one to two percent thereafter in the following months of use. At higher temperatures, the self-discharge on all battery chemistry increases. The self-discharge of a battery increases with age and usage. Once a battery exhibits high self-discharge, little can be done to reverse the effect.

Premature Voltage Cut-Off – some devices like PDAs do not fully utilize the low-end voltage spectrum of a battery. The pda device itself, for example cuts off before the designated end-of-discharge voltage is reached and battery power remains unused. For example, a pda that is powered with a single-cell Li‑ion battery and is designed to cut-off at 3.7V may actually cut-off at 3.3V. Obviously the full potential of the battery and the device is lost (not utilized).

Now that we have looked at how the chemical changes in a battery effect battery degradation and power loss and contribute to the eventual total loss of the battery I will, in my next article, discuss why battery degradation occurs in the first place.

What is A Battery?

A battery is a device that converts chemical energy into electrical energy. Batteries have two electrodes, an anode (the positive end) and a cathode (the negative end). In between the battery’s two electrodes runs an electrical current caused primarily from a voltage differential between the anode and cathode. The voltage runs through a chemical called an electrolyte (which can be either liquid or solid). This battery consisting of two electrodes is called a voltaic cell.

The first inclination that an electrical path-way from an anode to a cathode within a battery or in this first instance “a frog” occurred in 1786, when Count Luigi Galvani (an Italian anatomist, 1737-1798) found that when the muscles of a dead frog were touched by two pieces of different metals, the muscle tissue twitched.

This led to idea by Count Alessandro Giuseppe Antonio Anastasio Volta (Feb. 18, 1745- March 5, 1827), an Italian physicist who realized that the twitching was caused by an electrical current that was created by chemicals. Volta’s discovery led to the invention of the chemical battery (also called the voltaic pile) in 1800. His first voltaic piles were made from zinc and silver plates (separated by a cloth) put in a salt water bath. Volta improved the pile, using zinc and copper in a weak sulfuric acid bath and thus invented the first generator of continuous electrical current.

In 1820, the French physicist André-Marie Ampère discovered many of the laws governing the relationship between electricity and magnetism, along with how a battery works. Ampere found that electrical current move through conductors, and that electrical charges flow from one electrode to the other. Ampere invented the astatic needle, which detected electrical currents.

In an interesting side bar regarding Ampère and Volta:

From Volta’s work we get the Volt – or V – which is an electrical measure of energy potential. For example you can think of energy potential as the pressure being exerted by all the electrons of a PDA Battery’s negative terminal as they try to move to the positive terminal.

From Ampère’s work we get Amps – or A – which is measures the volume of electrons passing through a wire in a one second. One Amp equals 6.25 x 1018 electrons per second.

From both Volts and Amps we get the formula for a battery’s full potential measured in Watts: Volts x Amps = Watts. Watts are important because a watt represents the electrical energy spent by a battery (power generator) and used by an electrical device. Watts in effect is the measure of the amount of work done by certain amperage (amount) of electric current at a certain pressure or voltage.

The batteries we use today are simply variations of the early battery or voltaic pile. Today’s battery’s are made up of plates of reactive chemicals separated by barriers, being polarized so all the electrons gather on one side. The side that all the electrons gather on becomes negatively charged, and the other side becomes positively charged. Connecting a device creates a current and the electrons flow through the device to the positive side. At the same time, an electrochemical reaction takes place inside the batteries to replenish the electrons.

The effect is a chemical process that creates electrical energy with one downside: about 80 percent of the energy put into batteries is lost through this process.

Though the battery maybe inefficient we still need the battery, especially battery replacements that are inexpensive. We are power hungry consumers. We like our power and lot’s of it. Lithium-ion batteries (Li-ions) are generally considered the most powerful, offering the same energy as nickel metal hydride (NiMH) batteries, with 20 to 30 percent less weight. They are expensive compared to older battery technologies, but are valued for high-power portable applications, such as laptops, cell phones, and PDAs.

Until next time – Dan Hagopian, BatteryShip.com