(This is about rechargeable Lithium batteries that are common in portable devices. For a few quick tips on extending the battery life and squeezing the most out of it, scroll to the bottom of this post)
The modern world is said to be squeezed in all kinds of wanted and unwanted tensions. Well, that is true. But its high time we should take a break from all these. May be we should work on the way we deal with different problems and happenings. huh, I deviated..!! While every one has a million reasons to get tensed, there is one common problem that every human fear of. Its the Battery Backup. Almost all people in the modern world use at least one portable device which work on the stored energy in a battery. The most common one being the mobile phone, along with portable music and video players. And there are tablets, palm tops, lap tops, digital cameras, camcorders, navigation devices and many more.. its a big list!!
THE BATTERY
A Battery is a teeny power house. It provides power in the form of electricity that can drive various devices. A powerhouse which actually is a small chemical laboratory where some chemical reactions take place generating electricity. Quite interesting! We carry a chemical laboratory with us wherever we go..! Now the problem is that, there is nothing called as infinite power. When the chemicals that take part in the reaction run out, the battery dies. Another problem – the reactants can’t regenerate all by its own. So now that we used up all the reactants we need to regenerate them and this is what we call charging the battery. All the chemical reactions that took place to give us electrical energy while the battery was discharging are reversed during the charging process. Charging is done by connecting the battery to a controlled electrical supply. So that is the outline of how a battery charges and discharges.
BATTERY LIFE
By saying battery life, it can either mean the complete life span of the cell or the time for which a battery can power a device in one full charge. The complete life span of a battery is defined by the number of times a battery can be recharged. This is called as charge/discharge cycle. One cycle corresponds to charging the battery (to any level; whether full or partial) and then discharging (using) it. Modern batteries (Lithium cells) have large number of charge/discharge cycles (about 400 or 500). It also depends on the charging behaviour (will explain it). The Battery Backup. Now this is really important when you are out travelling and cannot find a source to recharge the cell. Backup is the time for which the charged battery can power the device in which it is used. It strictly depends on the power or current consumption of the device, usage behaviour and environmental parameters like temperature. Everyone wants the backup time to be loooooong. This is much dependent on the battery capacity and other factors just mentioned before.
BATTERY RATING AND CAPACITY
Every battery has a capacity as we humans do. While some can lift 50 kilograms with real ease some others struggle to do so (just an example). The battery capacity mentions how long the power house will last for a specified amount of current output from it. For example, on the cell phone batteries there will be figures like ‘3.7V, 1500mAh’ or ‘3.7V, 1250mAh’ or the likes. Consider the first one – 3.7V, 1500mAh. 1500 mAh is equivalent to 1.5Ah (mAh is milli ampere-hour and Ah is ampere-hour). The figures mean that the battery’s terminal voltage (or output) is 3.7V and it will last for one hour if current is drawn from it at the rate of 1.5A. That is, after 1 hour of operation the battery dies if it supplies a current of 1.5A for one hour. Now, if the device takes current from battery at the rate of 0.5Ah, the cell will last for 3 hours. Thus backup time = (Battery rating in Ah)/(Device current usage in Ah) From this we can understand that, if we use a battery of larger rating (say 3Ah) the device will last longer. In the above case, 3/0.5 = 6 hrs
STRETCHING THE LIFE
Starting with the life span. The Lithium batteries are a lot different from the old NiCad ones. The charging and usage method are also much different. But unfortunately most of the user manuals of portable devices follow the instructions that are valid with NiCad cells and not true with Lithium ones. One of the biggest blunders is that, they say allow the battery to completely discharge before charging it again so that it helps in improving the cell life. This was true with Ni-Cad cells. In the case of Lithium cells, its better to topup the battery as fast as possible. That is it is better not to allow the battery to run down below 40 percent of the fully charged state. The advantage is that, such frequent top ups will increase the battery life cycles. (But for NiCad cells this was different. Frequent charging reduced their life) For example, consider a battery of life 500 cylces. If this battery is charged when the capacity drops to 50% then it can be used for more than 1200 cycles this way. And if the recharge is done when the capacity drops by 10%, the cycle number increases as high as around 5000 cycles. But occasionally (like once in a month) discharging the batteries completely till the device switches off and then charging it fully is a good process. It helps in calibrating the voltage meter and is termed to be a good thing for the cell.
SQUEEZING THE BEST OUT
The most important thing is, with no doubt, the backup time. By caring a little, the battery backup can be stretched to the maximum.
- Temperature is the biggest enemy of our little power house. If the heat is large, the battery is strained and badly affect the backup time as well as the life span. Its always advised to keep the temperature low. But how? Well, a battery when delivers large power expels a lot of heat. Doing energy hungry activities on the device like hardcore gaming, recording High Definition videos, capturing photos, making a call and the likes draw a lot of power from the battery. Thus elevating the working temperature and this brings an adverse effect on the battery life. But these cant be avoided. It may strictly be taken care of not to use a phone to make a call or attend one, browse the web, record a video and play games while the device is plugged to an energy source for charging. Because that liberates a lot of heat and badly affect the battery life.
- Try to keep the display brightness to the lowest possible level. Display back light eats a lot of power.
- Don’t frequently switch off and on the device. This is an energy hungry activity.
- For laptops, don’t plug in usb devices or other peripherals if not needed. Also keep a larger RAM and lower virtual memory. This helps the hard disc to rest more. The automatic switch off time of display, n/w card and everything else must be set to a lower value
- On a phone, don’t keep the data connection active if not needed.
- Always remember to switch off the blue-tooth after use. This saves power as well as the privacy.
- Automatic wifi scanning may be switched off. Wifi is really hard on the battery.
- Try to use the lowest value of back light time of displays in the devices.
- Screen savers save battery.
- Don’t keep applications open in phones, tablets and laptops in the background unless necessary. More applications means more memory and so more power.
- Understand the capacity of battery and use the devices wisely according to the limits.
- This might sound crazy but, if the device seem to heat up a lot, open the battery cover for better air flow to cool it down fast (strictly not in the case of laptops).
- Do not over charge batteries. Its the worst case that kills a good cell.
- If available and supported, find a power monitor application for the device and monitor power usage of various applications so that those can be killed if needed (A good task manager may be made use of for this process)
- Find updates from the manufacturer’s website. The updates mostly contain tweaks that reduce battery usage.
- New technologies will be more efficient than the existing ones, in most cases. Go for them if needed.
- If the present battery seems to be insufficient, find another one with larger capacity (larger Ah or Wh – Watt hour rating) if available. Or carry a spare one.
FiNaL NoTe: Never Waste Energy
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