External Power Adapters : Power Adapters Tips

There are four types of rechargeable batteries: nickel metal-hydride (NiMH), nickel cadmium (NiCad), rechargeable alkaline, and lithium ion.. They come in many different sizes and use different combinations of chemicals. And commonly used secondary cell chemistries are lead acid, nickel cadmium (NiCad), nickel metal hydride (NiMH), lithium ion (Li-ion), and lithium ion polymer (Li-ion polymer).

Sanyo Eneloop 8 Pack AA NiMH Pre-Charged Rechargeable Batteries

The Best Rechargeable Batteries Of 2009

Types of Rechargeable Batteries
NiMH rechargeable batteries typically perform better than NiCads and are free of toxic heavy metals. Generally speaking, NiMH is the best all-around choice for most rechargeable battery applications. As an added bonus, most NiMH battery charger systems can accommodate NiCad batteries too (although the opposite is not true).

NiCads are being phased out in favor of NiMHs not only because they are losing the performance war, but also because of their inconvenience; the heavy metals used within the NiCad are toxic and require special disposal needs.

Rechargeable alkaline batteries have only two real advantages over NiMHs and NiCads: low cost and no need for special recycling. Otherwise, their long-term performance and recharge characteristics make these batteries a poor choice. Rechargeable alkaline batteries also require a special charger, which reminds me: don’t ever confuse rechargeable alkalines with the typical disposable alkaline batteries that are sold everywhere from 99-cent stores to the local grocery market – although some people do it, those batteries cannot be safely charged.

Lithium Ion batteries have great performance and can go unused for long periods without losing their charge. The big drawback is their price; not only are lithium ion batteries much more expensive than other types of rechargeable batteries, but they also require a special charger. Use them for rarely-used or high-drain devices like laptop computers, digital cameras, cell phones or portable television

Rechargeable Batteries Comparison Table
Here is a trade summary of the four basic options to help you decide which rechargeable battery is right for you. (lenpenzo dot com)

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Battery Charger
The energy used to charge rechargeable batteries mostly comes from AC current (mains electricity) using an adapter unit. Most battery chargers can take several hours to charge a battery. Most batteries can be charged in far less time than the most common simple battery chargers are capable of. Duracell and Rayovac now sell chargers that can charge AA- and AAA-size NiMH batteries in just 15 minutes; Energizer sells chargers that can additionally charge C/D-size and 9 V NiMH batteries. However, high rates of charging (eg. 15 minute charger, 1 hour chargers) will cause long term damage to NiMH and most other rechargeable batteries.

La Crosse Technology BC-9009 AlphaPower Battery Charger

Best Battery Charger

Rechargeable batteries are susceptible to damage due to reverse charging if they are fully discharged. Fully integrated battery chargers that optimize the charging current are available.

Also, attempting to recharge non-rechargeable batteries has a small chance of causing a battery explosion.

Find on Amazon Rechargeable Batteries and Charger
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Computer power supplies is the most critical component, and it may be one of the most overlooked. It is just taken for granted that it will always be there and working properly. A top of the line processor and ultra powerful video card do nothing if a system does not receive the ample, stable power it demands. Having quality components providing and regulating the power supplied to a computer is critical, and this brief overview looks at a few areas worth consideration.

Power Supplies
Computer Power supplies are sold in terms of their total power output, in terms of wattage. Choosing a power supply with enough power shouldn’t be much of a problem, as having more power than you need is never a bad thing.

It just indicates the total power available to the various lines inside the computer. In addition to checking out the total wattage of a power supply, looking for strong amperage ratings on the 3.3V, 5V, and 12V lines is also recommended, as power supplies with identical total power ratings may distribute the power to the various lines in different quantities.

A typical ATX power supply, such as this Coolmax 700W unit, measures 3.35" Height x 5.51" Width x 5.91" Depth and features two cooling fans to not only cool the power supply, but to also help draw hot air out of the computer. A typical mATX power supply, such as this TR2 Series 430W unit, measures 2.5” x 5” x 4” and due to the smaller size features just one cooling fan. mATX cases are generally much smaller than ATX cases, and therefore have smaller power supplies, with generally lower power ratings, and fewer connectors.

The connectors on a power supply also deserve consideration. Up until recently power supplies had a fixed number of connections, and if you needed more, you needed to use splitters to distribute the power to all the components.

Many manufacturers now offer computer power supplies that consume less energy thanks to high quality internal components, advanced designs, and active power factor correction. These units are now able to provide the same power to the components in a computer, but due to increased efficiency, draw less power from the electrical outlet.

Surge Protectors
Surge protectors come in all shapes and styles. The Fellowes Surge Protector protects up to 10 devices from surges, as well as offering line conditioning and ports to protect your phone line.

Uninterruptible Power Supplies
Many people familiar with Uninterruptible power supplies (UPS) know that they can keep a computer up and running during a total power failure, but don’t know what else they do. A continuous UPS always has the devices connected to it running off of battery power, while the batteries are recharged by the normal electrical connection.

A computer system is only as strong as its weakest feature, and many times that distinction falls on the power supply and related components. By choosing a quality power supply, surge protector, and perhaps a UPS, one can make sure that they have adequately strong and stable power to keep their system running now, as well as down the road when upgrades may increase the demand on their system.