Battery technology is changing every day and this is a good thing for consumers. Rechargeable Batteries can be found in everything from electronics, tools and even cars but when choosing a product how do you know which battery will give you the best performance at a decent price.
For consumers there are two types of batteries that you will come into contact with: OEM Manufacturer Batteries that are sealed special batteries only fitting the product they serve and General Use Batteries that come in a standard size AA, C, D, 9volt.
Battery Strengths are rated in mAh and you may see batteries of the same size rated at EX. 800 mAh or 2500 mAh and the 2500 one is stronger with a longer life. Ah or Amp Hour is a rating of how much energy a battery can store. If you pick a battery with a Higher Amp Hour rating it will not cause incompatibilities.
Voltage is the level of Energy or pressure of electricity that the battery can give off. Some Higher rated batteries may produce a higher voltage and it is important to pick the correct voltage for your product. For instance a Car battery works at 12 volts while the lights in your home work at 115 volts. Both lights are bright but require different voltages to work correctly.
With Standard Size replaceable batteries you can choose which battery type fits your use patterns best and for the most part unless the manufacturer warns against their use you can interchange battery types as long as you don’t mix types within the same product. This means if you have a Digital Camera that came with NiCad batteries you can usually upgrade to stronger NiMH batteries with no problems.
One of the only reasons you would not want to change the type of rechargeable is when the device includes its own internal charger like a radio that can run on battery or AC voltage which will charge the batteries when it is plugged into a wall outlet.
NiCad, NiMH and Li-Ion all require different charging devices or a device that can be set to charge more then one type of battery.
If you are choosing a product like a Cordless Drill you may find that the charger you have for your NiCad Batteries will also accept NiMH batteries because the shape of the battery fits in the charger but you should not charge your batteries with a charger rated for a different battery type or you could cause damage to the battery and sometimes melt the charger causing a fire.
So lets look at the differences and benefits of these three battery types.
All batteries whether rechargeable or standard contain materials that are harmful for the enviroment if not handled correctly so you should always recycle your batteries.
NiCad Batteries were one of the first high grade rechargeable batteries on the market. The drawback of NiCad technology was that the battery would lose potential power over the life and could also lose power if used or charged incorrectly. This loss of power due to improper use is called Charging Memory and means that when you use NiCad Batteries they need to be fully discharged before you recharge them. Many people would use their batteries for a few days knowing that they drained 40% of the charge and then because they were going on a trip they would recharge them when they still had 60% good use left. This recharging would lower the amount of energy that you could hold in the battery and shorten times between charges. Unfortunately there is no cure for battery memory and the only solution is to purchase a new battery. NiCad Batteries were also often rated at a lower power level then standard batteries which meant that some devices such as cameras could not use a rechargeable because they wouldn’t have enough energy to even start them.
NiMH Batteries relieved the problem of Charging Memory Loss and would allow the user to recharge the battery at any point in its discharge level. This meant that contractors could come home and place their batteries in the charger overnight and would not have to run their tools down and recharge them on the job just to keep the battery in good condition. NiMH batteries are also stronger and last longer on charges then NiCad Batteries meaning more devices could be used for longer periods of time. Instead of just rechargeable drills the introduction of stronger batteries meant circular and reciprocating saws could also be relied on as being almost as strong as their plugin counterparts. One set of batteries may last you half a day instead of just a few minutes.
Li-Ion Batteries have taken Battery Technology to the next level. Just like NiMH batteries did for NiCad … Li-Ion battery have extended the life and increased the strength of rechargeables. Because Li-Ion batteries are smaller the same size battery when compared with other technology will always be stronger however their concentrated strength has opened up the possibility of reduced size and weight in most applications. This is really visible in cell phone technology as the batteries progressed from NiCad to NiMH then to Li-Ion the size of cellphones decreased they are now lighter and thinner and instead of needing an external charger space is now available to include internal charging.
So which battery is best for your application?
For the most part if Li-Ion batteries are available you should choose them because they are smaller and stronger however because of the higher cost you may find NiMH Tools and Electronics cheaper. Both of these technologies will give you a decent amount of power however the NiMH tool will have larger, heavier batteries that require more frequent charging.
One thing to note Li-Ion batteries do not always mean a more expensive tool. Ryobi brand Cordless tools which are one of the cheapest on the market began using Li-Ion batteries in their standard brand of tools. This doesn’t mean Ryobi should be picked over other brands because it is a Consumer grade not Commercial grade tool but it does go to show that retooling product lines can allow you to make a better product and still keep the price down.
For Standard Replaceable Rechargeables that most of us use in our consumer electronics Li-Ion Batteries are not readily available. This could be due to Toyota grabbing up all the Li-Ion material to use in their Hybrid Vehicles but for now if you are using NiCad Batteries in your portable radio that does not have an internal charger or your Digital Camera then you can upgrade to NiMH and have longer life and extend your time between charges.