I am on a project building a cube sat and I am concerned with mitigating the risk of battery failure during operation. For those engineers scientists out there, what are the biggest risks I need to worry about for the battery? For example, is it the extreme environmental conditions, cell design failure, degradation, or something else?

We are using a Li-ion prismatic cell. Our battery specs are as following: voltage 3 to 4.2 V, and capacity 1.8 Ah at C/5 rate at 23° C.

here? this bunch of idiots? you've got to be kidding…

please review the literature: premature battery failures are generally due to shorted or open cells due to temperature fluctuations.

to be successful in this field you need to show better judgement. please reconsider your research goals.

One should realize that wheelchair battery charger must be fully operational in transferring electricity and its proper function. Find out how wheelchair chargers affect the efficiency of the battery is your primary concern.

An essential part of your powered wheelchair is the stored electric energy in your battery. It’s the lifeline of your electric wheelchair as without it you cannot move into your desired position. It is very essential for everyday living especially for those who depend on their electric wheelchair as their primary source of transportation.

There are lost of newly designed batteries that can suit your need in electric wheelchairs. Wheelchair batteries are designed to be reused for a number of times. You must have a compatible charger on it for you can use it all over again. Three types of batteries are available in the market. First is wet, then gel and last is AGM. These different types of batteries must have specific chargers.

These chargers are classified into two types:

Jed Baguio
http://www.articlesbase.com/health-articles/what-you-should-know-about-your-wheelchair-battery-charger-93285.html

There are two main types of solar power, solar thermal and photovoltaic. Solar thermal uses the sun light’s infrared energy to either heat a liquid or to warm a mass of material that will later on release its stored heat. Harnessing solar thermal energy involves building a house in such a way to collect the sun’s heat during the day and radiate it into the home during the evening. However, in the summer time the house’s construction uses mass to keep the sun’s heat out of the home.

Solar photovoltaic energy converting sun light into electrical energy. The most commonly associated component are the photovoltaic panels or solar panels that you see mounted on roofs.

This article will be focusing on how photovoltaic solar power (solar panels) and systems work.

Why are solar photovoltaic panels always on the south (or north) side of the roof?

In order to get the maximum electrical output from photovoltaic panels they need to be oriented to solar south in the northern hemisphere and solar north in the southern hemisphere. Solar north and solar south are the same as magnetic or compass north or south. There is about a fifteen degree difference between them.

Most solar photovoltaic panels are set at home latitude plus fifteen degrees or home latitude minus fifteen degrees. Depending on if you want a summer or winter bias to the angle of the solar panels. In higher latitudinal areas it makes more sense to have the photovoltaic panels set on a winter bias, so that during the winter the solar panels still get enough sun light to produce electricity.

How does a photovoltaic cell produce electricity?

A solar panel consists of a collection of photovoltaic cells. Each photovoltaic cell is made up of silicon wafer. Silicon in its pure state is a poor electrical conductor. During the manufacturing process, an impurity is added to the silicon so that when the photons (light) strikes the wafer electrons are released and create electrical current.

The type of electrical current produced by a solar panel is a low voltage direct current, or DC, typically in the range of six to twenty four volts. Photovoltaic panels have a nominal output voltage of 12 volts and an effective operating voltage of 17 or more volts.

A solar panel’s electrical output is affected by several factors. They are angle of the photovoltaic panels to the sun, time of day, time of the year and weather conditions. Solar photovoltaic panels produce more electricity during the middle of the day when the sun is directly overhead compared to the early morning and late evening when the sun light is striking the solar panel at a shallow angle.

Components of a residential solar power system

A residential solar power system consists of four components are: photovoltaic panels, charging controller, battery pack and an inverter. The photovoltaic panels convert sun light into electricity. The electricity is sent to the charging controller who keeps the battery pack fully charged, but not over charged. The battery pack sends the electricity to the inverter who converts the DC voltage to household AC at 120 volts and 60 hertz.

Photovoltaic panel

The output of a solar panel is stated in watts. The wattage is stated is typically for peak sun hours. Since the amount of sun light varies through the course of a day, to level out the variations the peak sun hours has been adopted by most manufactures to help installers and customer’s compare different solar panel models.

Suppose a solar panel is rated for 100 watts and an average of six peak sun hours is available per day. Then the solar panel would produce 100 watts * 6 peak hours = 600 watt hours of electricity or 0.6 kilo watt hours (KWh).

Charging controller

Charging controller or charge regulator controls the charging of the battery pack. It continually monitors the battery pack’s charge state. If the batteries are low, it will send electricity from the solar panels to the batteries. It also prevents over charging of the battery pack.

Don’t allow someone to convince you that a charging controller is not really required. Directly connecting the photovoltaic panels to the battery pack can permanently damage the batteries and possibly cause them to explode.

Battery pack

The battery pack’s purpose is to store electricity generated by the solar panels during the day and then at night or during extremely cloudy days provide electricity to the inverter.

The battery pack typically consists of lead acid batteries. Lead acid batteries are relatively inexpensive and readily available. There are many different types, sizes and capacities of batteries available. The most popular are gel cell and AGM deep cycle batteries because they are maintenance free and last a lot longer than wet cell lead acid batteries.

The most important thing to remember about the batteries is that the need to be deep cycle. Deep cycle batteries are designed to be discharged then recharged hundreds if not thousands of times. A deep cycle battery is designed to discharged to nearly empty, but not completely and then be slowly recharged over time. A common mistake for home owners is to think that they can use automotive batteries instead of deep cycle batteries. Car batteries are shallow cycle batteries. They are designed to discharge a lot of current quickly and then be immediately recharged.

Inverter

An inverter converts the DC electricity stored in the battery pack into household 120V AC. Almost everything in your home is powered by 120V electricity. Things like table lamps, freezer, lights, motors, dishwasher, and so on.

There are two main types of inverters sine wave and modified sine wave. The power company provides electricity as a sine wave. The electricity’s charge value goes smoothly from positive 120V to 0V to negative 120V and then back up to 0V and finally up to positive 120V. Then the cycle begins all over again. The time it takes to go through the entire cycle is one second.

Modified sine wave is also known as a square wave. Here the electricity’s charge value goes from positive 120V to negative -120 volts in effectively zero seconds.

Most household devices will function on a modified sine wave power. Light bulbs and motors will work, just not quite as efficiently as they would on sine wave electricity. However, there are some electronic devices that will not work on square wave electricity. It will be necessary to check with the manufacture to determine if the device will work on square wave electricity.

Now you have a basic understanding of solar power how it works to power your home. Now you have enough information about how solar power works to determine if it is a technology that you would want to invest in for your house.

Wilhelm Williams
http://www.articlesbase.com/home-improvement-articles/solar-power-how-it-works-to-power-your-home-150901.html

Millions of people have fallen in love with their digital camera; and for good reason. They are compact making them easy to tote along anywhere a person may wander, they are capable of producing images of outstanding quality which can easily be shared online with others anywhere in the world, and with digital storage, they are a space saving wonder. In addition, digital cameras allow users to save the expense of film and developing. But perhaps the greatest attraction of these cameras is the control they provide over the images one creates during the editing process.

Unfortunately, most of those who love digital cameras have also come to know their dark side; their thirst for power. From the first touch of the button to power a digital camera on, setting the focus, shutter speed, zooming, and providing a flash for image capture, to reviewing images taken and editing, these cameras are energy junkies.

The good news is that there are things that can be done to help to make it easier to live with power craving cameras and to curb their appetite. Certainly, having a camera with rechargeable batteries is by far the best option and charging the battery per manufacturer’s guidelines can help sustain optimal functioning. For the people who love their digital camera, there are also steps that can be taken in the way they use it to help reduce the rate of power consumption.

• When finished shooting, remove the batteries from the camera if it will not be used for another 2 or 3 weeks. This will prevent a trickling discharge that can occur when left in the camera.

• Use the on/off function appropriately. Certainly a digital camera should not be left on for any extended period of time as the energy is wasted. However, if another shot will be taken within a few minutes it is better to leave the camera on as it consumes a great deal of energy to power on/off. If the camera has a sleep mode, it is best to set the timer for that function to the shortest interval in case the user forgets to turn the camera off.

• Disable or don’t use features that aren’t needed. Zoom for instance uses a great deal of power. If the same result can easily be achieved by simply moving the subject or stepping closer, do that instead. Use of the flash function is also energy intensive. Flash should be used only when it will be effective. For instance, if lighting is already sufficient or the subject is out of flash range anyway, don’t use the flash function.

• When possible use the viewfinder to set up a shot as the LCD screen consumes a great deal of battery power. Use of the LCD screen can improve some shots such as in the case of close-up/macro photography but in most instances use of the viewfinder is sufficient. (Remember, photographers operated without LCD screens for most of the history of photography!)

• Use other power sources when appropriate. For instance use an AC adapter when downloading images and use the computer for review and image deletion rather than performing such functions directly on the camera.

• Do things manually when feasible. From powering the camera off to focusing; auto anything takes more power.

• Some experts indicate that some types of media storage consume more energy as well. For instance, Compact Flash is said to be a more energy conscious form of storage than MicroDrive Media.

Certainly, the many features offered on a digital camera are convenient and desirable. Users merely need to be aware of the tremendous demands placed on the camera battery by these same features. Understanding this allows a digital camera owner to make a choice between ease of use and conservation of the battery.

Christine Peppler
http://www.articlesbase.com/electronics-articles/battery-devouring-digital-cameras-and-the-people-who-love-them-87378.html

When you think of portability many people believed that you would not be able to get the power and functionality as compared to a desktop system, today is not true. Desktops are the preferred computer because of the ability to add peripherals and the power are much more than a laptop, but today laptops are able to add peripherals and have the computer power and have the ability to snap into a docking station which emulates a desktop. That has now changed and laptops are becoming affordable, light weight, faster and the ability to add many peripherals via USB.

Laptop computers are great portable offices, and as technology increases and speeds of computers increase, we are seeing battery life also increase and provide longer usage time with out the need to be plugged in. An extra battery is always a wise purchase when buying a used laptop. The batteries on many systems only last for about 2 years so if you get more life out of the battery you are one of the lucky ones. Battery life varies with the efficiency of the processor, so check out battery life in any reviews you read. When looking at the weight of the laptop don’t forget to add in the weight of the battery chargers and other accessories, this should be included in the weight of the laptop.

Manufactures are able to create tiny screens, even as small as 8 inches, this size screen is great for portability, but many people are finding that the fonts and images are to small and to use they need to start squinting. The size of the screen is also important. When looking at laptops look at the hinges of the screen and make sure they are strong and do not look like they would crack or separate from the laptop. Every so often you need to clean your screen and get the dust out of your keyboard, make sure you handle the screen carefully because the screen is fragile and can break easily.

Wireless is the wave of the future, so when looking to purchase a laptop make sure you get one with wireless built in. To use the wireless you will need a wireless router at home. This is always good to remember if you are using a wireless system make sure you make it secure so no one can steal your data or use your wireless system.

There is a variety of different types of memory, and it is important that you choose memory that is compatible with your notebook computer. Many computer owners don’t like to upgrade because of many reasons: they do not have the knowledge, fear of voiding the warranty or ruining their computers and some people don’t know what to order, or by opening the computer they might break the system and need to pay more to get it fixed. Like a lot of things in life, a computer memory upgrade seems more complicated than it actually is.

With today computers having the ability to add many peripherals be sure that the laptop comes with many USB ports to add devices like a mouse, printer, digital camera, etc.

If you are on tight budget, buying a refurbished laptop is a great idea. Many manufactures have refurbished laptops and will sell them at a reduced price which will save a lot of money. Many of the refurbished laptops even come with warranties.

David Fishman
http://www.articlesbase.com/computers-articles/laptops-are-getting-smaller-and-smaller-96790.html

With all the features digital cameras have these days, you may find keeping batteries a problem. This could well be your biggest expense, but there are some things you can do to increase the length of time your batteries stay charged. Let’s start with the three biggest sources of power drain.

The LCD screen takes up the most power. It is possible to turn this feature off unless you really feel the need for it. Using the camera’s viewfinder will conserve power. Another big power drain is the flash. Whenever you can, use natural lighting to take your photos and turn off the flash. This will help save your battery for times when you absolutely need the flash. A third drain on your battery is constantly using your zoom. It takes more power zooming in and out than it does keeping your zoom at a steady place. Try to find a setting you like and sticking with it as much as possible..
Some other things you can do to make your battery last longer are:: http://www.review5.info

* Make sure Power Saving mode is on, or simply switch off your camera when you’re not using it.

* In cold weather, keep your camera and batteries warm in your jacket until you are ready to use them. The cold drains batteries very quickly.

* Store batteries in a cool, dry location away from sunlight and other heat sources.

* Avoid unnecessary playback of your already taken images. Try to decide when you take the picture if it is a “keeper” or needs deleted and then refrain from reviewing until the pictures are downloaded to your computer.

* Use the AC adapter. Most digital cameras have an adapter that allows you to plug directly into a power point. If you don’t plan on moving around a lot and are near an outlet, the AC adapter will increase the life of your batteries.

Needing to buy more or recharge your battery is something you won’t be able to avoid completely, but with a few precautions this won’t be needed as often.

Review Host
http://www.articlesbase.com/computers-articles/making-your-digital-camera-battery-last-longer-138281.html

Everyone occasionally feels a need for inner rejuvenation. Whether you want simply to reclaim your inner peace in the midst of a hectic life, or do some soul searching over your life directions, or go deeper into your spiritual life, going on retreat can be a perfect solution.

A true retreat is much more than a vacation – it can be a time of conscious, spiritual opening, of making an enjoyable effort to rise to an entirely new state of awareness. Here are a few tips for a retreat experience that’s both relaxing and spiritually rewarding.

Find the Right Environment

Seek out a place that is harmonious with your goals. The right environment can give you a tremendous boost – while the wrong one can leave you feeling flat, or even work against you. So do your homework and ask some questions, because even similar-seeming places can have quite different emphases.

Do you want a highly structured retreat, or do you want freedom to do what inspires you? Do you think you might need some guidance in customizing your retreat, or do you know exactly what you want to do? Choose a retreat center that offers what you seek.

If it’s spiritual depth you’re after, choose a place with an established spiritual tradition. Then you’ll be like a surfer who chooses a beach with the best waves, rather than trying somehow to create waves yourself.

Look also for a place that uplifts you with its beautiful natural surroundings, and with space to be alone whenever you wish it.

If you’re new to retreating, go to a retreat center that offers personal guidance. Optional, guided group activities are also a plus. Even experienced retreatants find that occasionally tapping into the magnetism of group activities can be invaluable for keeping their energy high and focused. For example, The Expanding Light Spiritual Retreat Center in California offers twice-daily sessions of yoga postures and meditation.

Prepare Yourself

Eat right and get rested before you go on retreat; otherwise, you may need the first day or two of your retreat just to pull yourself together. If you already engage in spiritual practices, get a head start by putting extra energy into them before departing. You’ll be glad you did.

As soon as you leave home, put all problems forcefully out of your mind. Preoccupation with problems can suffocate your retreat, while a worry-free retreat can actually help you solve problems more effectively by getting you into “solution consciousness” rather than “problem consciousness.”

Plan Variety in Your Retreat

Who wants to go on a retreat that seems like boot camp? Let it be fun, and plan a variety of activities. For example, you might use the mornings for your most interiorized efforts: prayer, meditation, journal writing, or spiritual reading. Then be more expansive in the afternoons: walk in nature, do something creative, or listen to uplifting music or lecture tapes. Reserve your evenings for lighter fare: a spiritual video, a humorous book, or simply relaxed, quality time with like-minded people. And always allow for the inspiration of the moment; don’t be locked into anyone’s agenda – even your own.

Keep Perspective

Your free time is precious, and it’s only natural to be concerned over whether you’re doing it “right.” But there’s no magic formula for a retreat. Just find a flow that works for you, and go with it. Remember, what you do is not nearly as important as whether your inspiration and “joy level” are high. You don’t have to pray and meditate all day long; few people can do that constructively, anyway. You don’t have to stay in silence or solitude, though many people find these beneficial. And don’t “over-retreat”: if you’re a first-timer, 2–4 days is plenty. Focus on enjoyment, rather than “should’s.”

Above All, Relax and Enjoy Yourself

Don’t put pressure on yourself to see immediate, dramatic results. When you go on retreat, you are planting a spiritual seed. If you water it by your own continuing spiritual efforts, in time it will surely sprout into the flower of peace and joy that you seek.

Gyandev Mccord
http://www.articlesbase.com/travel-tips-articles/recharge-your-spiritual-batteries-how-to-take-a-personal-retreat-125598.html

Most MP3 consumers would agree that the iPod is one of the best choices for an MP3 player, unique cutting edge styling coupled with superb sound quality and durability. There has been however, numerous moans and groans from various sources of MP3 authority that the iPod battery is something that could be improved upon. Isolated cases of iPods going dead after only as few months have been reported and by reading this article you should have a basic grasp on how to prolong the battery life of your iPod and general care.

An absolute must is to download the very latest software for your portable device. In an age where software updates are as about as frequent as the weather changes, it is imperative that you keep up to date with software and firmware changes. Secondly, use the HOLD switch. Yes thats right. How many times have you slipped your iPod inside your coat, jacket or trousers only to discover the next time you plug in them earphones you iPod is as dead as a dodo.

Speaking of earphones, remember if you use all them fancy accessories to make your iPod stand out from the crowd that actually this drains more resource power from your iPod so if you plan on using your iPod on a long car or train journey then maybe leaving some accessories at home is a good idea.

Temperature control is another factor in looking after your iPod battery. Your machine will work best at room temperature (at about 20 degrees). If you have left your iPod outside or even in the car overnight, then let it warm up inside first before using. As well as cold temperatures the same principle applies to extreme warm aswell. Be mindful of not letting your iPod out in the sun or leaving it laying on the dashboard of your car in the summer.

Regular charging of your Ipod is also very advisable. Do not let your iPod go dead flat. Try to get into the habit of leaving your iPod on charge at least once a week or even better every night before you go to bed.

Do you really need the backlighting facility? This is one of the major sources of power consumption on your iPod. There is an option to switch this off and you will be amazed on how much longer your iPod will last for before the need of a re-charge. Also try to avoid changing tracks to often if you can help it. Pressing the forward and back button on your machine executes major hard disk activity on your iPod which in turn drains massive battery power.

Finally, turning off the equalizer and using compressed songs is also good advice on keeping your iPod stay charged up for longer. Optimum cache size for your iPod is about 8 to 9mb so if your files and songs are longer then this then split these files in half. By following this short guide you will be sure to prolong the battery life of your iPod without the need for a recharge.

Martin Davies
http://www.articlesbase.com/electronics-articles/prolong-your-ipod-battery-life-95163.html

The Nissan Motor Corporation is on a roll and it is determined to bring to the market the right kinds of vehicles that the consumers are clamoring for. And this Asian car maker is going to be working with the NEC Corporation on this. Together, they would be developing lithium-ion batteries and they would also be producing them later on.

The lithium-ion batteries that the two great companies are going to create already have a bright future ahead of them. The companies did mention that they are going to use them on hybrid vehicles as well as on other forms of electric vehicles. A report has also mentioned the fact that the collaboration between Nissan and NEC has been created so that they could join forces and be a strong challenger to other companies like the Toyota Motor Corporation who is working with the Matsushita Electric Industrial Company.

Nissan is currently the third largest automobile manufacturer in Japan as per sales and it is working on making sure that it is going to be one of the greenest car makers and companies in the industry. They already have a program which they are calling the “Nissan Green Program 2010” and this one has been announced to the public just last December.

With this program, Nissan says that they are going to work on lessening down the amount of emissions in the atmosphere through engine technologies as well as vehicle technologies. And experts in the industry are saying that Nissan is probably going to use such developments and technologies in vehicles like gasoline electrics, plug-ins, 100% electric vehicles, and those that are based and running on ethanol. Of course, it also does seem that with the use of Nissan suspension bushing, the performance of their vehicles would still be topnotch.

Of course, Nissan and NEC are not only looking at the present but they are seeing well into the future. The companies are now saying that they are aiming at creating a breakthrough technology to make the auto industry even greener. If they are able to create a groundbreaking battery, they also promise to make sure that it is available in the market and would be available for use in most vehicles.

RyanThomas
http://www.articlesbase.com/automotive-articles/nissan-nec-to-work-on-new-lithiumion-batteries-133255.html

The man is out, and the smoke detector is beeping.. I am too short to check what kind of batteries it needs, but he wants to pick them up, before he gets home. Does anyone know what kind of batteries this thing takes? Thanks.

Most take 9 volt, some take AA