If you want to recharge your batteries, use Nickel-Metal Hydride (NiMH). These replace obsolete NiCad rechargeables. NiMH’s have much higher capacity than NiCd’s and don’t suffer from memory effect. Thomas Distributing and C. Crane have great prices on NiMH’s and carry the highest capacity D’s (9-11,000 mAh). Radio Shack sells them too but they cost a little more (and their D’s have less capacity). Also see our recommended chargers. NiMH’s are great all-around batteries but they have a high self-discharge rate (they go dead after a few months even if you don’t use them) so they’re not good for things like emergency flashlights or smoke detectors.

1. Battery Memory – When I first got my new cellphone, my friend recommended to fully drain the battery before recharging it. His reasoning was connected to the idea of battery memory. Allowing the battery to fully discharge then recharging to max, supposedly gives you the complete battery capacity. Otherwise, if you simply charged from the half way point to max battery capacity, the battery would treat the half way point as the empty point, thus cutting your battery capacity in half.

Problem is battery memory doesn’t apply to lithium batteries, this advice was meant for nickel based batteries. Fully discharging your lithium battery frequently can actually be quite harmful to your battery’s health, possibly rendering it completely unusable if energy levels go too low.

The good news is today’s lithium batteries have a safety circuit in place to insure the battery doesn’t reach the point of no return. The safety circuit isn’t fool proof though, if you leave your battery completely drained for a few days, even the circuit’s protective measures won’t save it.

2. Battery Calibration – There are some benefits to fully discharging your lithium battery periodically, for laptops this can be especially important. If you start to notice your battery meter becoming more and more inaccurate, it may be time for some battery calibration. Allow your lithium battery completely drain, then charge until the battery is full again. This will calibrate your battery giving you more accurate readings. This should be done once every 30 charges or when you notice battery readings are off.

3. Consequences of Heat – Another enemy of lithium battery life is heat. If you were to leave your laptop plugged in and running for a year, you should expect the lithium battery capacity to be anywhere between 60% to 80% of it’s original max capacity. This is why people that use their laptops as desktop replacements will notice greatly reduced battery life performance after one year of use. This issue can be resolved by removing the battery while using a corded power source. Now you may want to check with your manufacturer ahead of time to check for safety concerns, some manufacturers have mentioned problems such as moisture and dust collecting in the battery casing.

4. Battery Storage – If you don’t plan on using your lithium battery for prolonged periods of time, then you’ll want to reduce the charge level to 40% and place the battery in the fridge (not freezer). Storing the battery at 100% charge level applies unnecessary stress and can cause internal corrosion. On the other hand, if the charge is too low, the battery can become permanently unusable, due to battery self discharge. This is why manufacturers recommend storing your lithium batteries at 40% charge, rather than either extreme.

5. Turn off your Bluetooth – I find Bluetooth to be the most power hungry application; turn it off when you don’t use it

6. Disable sounds and vibrating alert – you don’t really need keypad tones to be on, do you? What about vibrating? It is surely useful on the meetings or in a cinema but most of time you’ll do just fine without it; I usually set up a vibrating profile to be used in places like cinema or theatre and in all other profiles I have vibrating turned off

7. Brightness – lower the brightness of your screen; not too low, otherwise you’ll destroy your vision

8. Setting the Power saver time-out and the Light time-out to the low values will help too (you’ll find them in the display settings)

9. If you are not using an application switch it off – you’ll get a list of all active applications by long pressing the menu button; this is a general rule that can be applied to any device

10. Games – it’s fun to play games on your way to school but they are power-hungry beasts; I can’t tell you not to play games but think about your battery when you are playing

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