Maintaining Battery Life - Advice

Hi Guys,

My old (2nd hand) laptop is finally giving up but I've bought a new one. Since the oldlaptop's battery was never in good shape anyway I was never concerned about best charging/storage strategies.

Anyway since it'll be a good couple of years before I can afford a new system I would like to keep the life of this battery in good shape for as long as possible.

Two main questions,

When is the best time to charge (when fully depleted or with say 10% left)?

Since I'll mainly be using this system at home is it a good idea to run from the mains with no battery installed? and if so what is the best state to store the battery when not in use (fully charged or fully depleted)?

Any other advice welcome.

 

Cheers Tony,

Agreed, with Ni-Cad's it's best to deplete completely before charging but this is a Li-Ion battery and I'm sure I read somewhere that they don't like being completely discharged (urban myth?)

I should have mentioned the battery type in my original post, sorry.

 

Storing the battery should be fully depleted. When in use let it go to about 12%-10%.

 

Thanks lj.

My lappy's going on a trip tomorrow so I'll keep the battery fully charged for now but I'll drain the battery completely before storing it after then. Unless others have suggestions?

 

Hi Wildfire, You made me do a Google on this subject as Laptops and cellphones use these batteries:
Lithium-ion Battery Life and Death
Lithium-ion battery packs are expensive, so if you want to make yours to last longer, here are some things to keep in mind:
• Lithium ion chemistry prefers partial discharge to deep discharge, so it's best to avoid taking the battery all the way down to zero. Since lithium-ion chemistry does not have a "memory ", you do not harm the battery pack with a partial discharge. If the voltage of a lithium-ion cell drops below a certain level, it's ruined.
• Lithium-ion batteries age. They only last two to three years, even if they are sitting on a shelf unused. So do not "avoid using" the battery with the thought that the battery pack will last five years. It won't. Also, if you are buying a new battery pack, you want to make sure it really is new. If it has been sitting on a shelf in the store for a year, it won't last very long. Manufacturing dates are important.
• Avoid heat, which degrades the batteries.
Li-ion Batteries
by zerotonin - July 29, 2005 9:25 AM PDT
In Reply to: how to prolong a Li-ion battery's life? by thefarseer
I worked for a cell phone company for 8 years and did a lot of research on this subject so I could properly inform my customers. There are basically 3 types of chemicals currently being used for cell phone and laptop batteries. Ni-cad, Ni-mh and Li-ion. There is a fourth making its way in Li-ion polymer. A couple things are consistent for all types of batteries no matter what chemical is inside. You must initially give the battery a 12-14 hour charge on the home charger. (Don't use a cigarette adapter for the first charge. This conditions the battery and don't take it off the charger that first time even if the charging indicator says it's full after 3 hours. Also the manufacturer's also state to run it thru 3 charge cycles. What that mean's is that you fully charge and fully drain 3 times. 1 full charge + 1 full drain = 1 charge cycle. Here's where the way you charge the battery starts to differ.

Ni-cad: Mostly only on older devices, has a "memory" effect, should be drained before a full charge is put on it, should be removed after overnight charge or can be overcharged and burnt out.

Ni-mh: Still used for some devices, has slight memory effect but not enough to have to fully drain before the recharge, should not be consistently left on charger after full charge that can eventually burn out battery and shorten usage time.

Li-ion and Li-ion polymer: Used on a lot of newer devices, has no "memory" effect, should be recharged as often as possible, actually likes to be charged and draining it regularly can cause the usage time to be shortened, can NEVER be overcharged so whenever you're near a charger put it on there. Besides those benefits a li-ion battery is lighter and smaller but the chemical can hold more charge than Ni-cad and Ni-mh.

So the one reply to your question said to error on the side of draining the li-ion batteries. This is incorrect information. You want to charge the battery before it gets below a 20% charge. Also batteries will not go bad from accidentally doing the incorrect charging procedure here and there but normally follow the correct procedure. One last note try to use the home charger more often than the cigarette lighter charger for best long term results. Cigarette lighter chargers do not give a full charge (about 95%) which in the long run can damage any type of battery listed.

Hope this helps

P.S. Every battery will have those abbreviations to tell you what chemical is inside the battery, even rechargable power tools which these charging procedures apply to also.
Figure 3: Longevity of lithium-ion as a function of charge and discharge rates.
A moderate charge and discharge puts less stress on the battery, resulting in a longer cycle life.

Battery experts agree that the life of lithium-ion depends on other factors than charge and discharge rates. Even though incremental improvements can be achieved with careful use of the battery, our environment and the services required are not always conducive to achieve optimal battery life. The longevity of a battery is often a direct result of the environmental stresses applied.
Simple Guidelines
• Avoid frequent full discharges because this puts additional strain on the battery. Several partial discharges with frequent recharges are better for lithium-ion than one deep one. Recharging a partially charged lithium-ion does not cause harm because there is no memory. (In this respect, lithium-ion differs from nickel-based batteries.) Short battery life in a laptop is mainly cause by heat rather than charge / discharge patterns.

• Batteries with fuel gauge (laptops) should be calibrated by applying a deliberate full discharge once every 30 charges. Running the pack down in the equipment does this. If ignored, the fuel gauge will become increasingly less accurate and in some cases cut off the device prematurely.

• Keep the lithium-ion battery cool. Avoid a hot car. For prolonged storage, keep the battery at a 40% charge level.

• Consider removing the battery from a laptop when running on fixed power. (Some laptop manufacturers are concerned about dust and moisture accumulating inside the battery casing.)

• Avoid purchasing spare lithium-ion batteries for later use. Observe manufacturing dates. Do not buy old stock, even if sold at clearance prices.

• If you have a spare lithium-ion battery, use one to the fullest and keep the other cool by placing it in the refrigerator. Do not freeze the battery. For best results, store the battery at 40% state-of-charge.

It would appear that you use the battery in your laptop (Li-ion) and make sure that the temperature is not too high for maximum life.
DO NOT FULLY DISCHARGE to store batteries.
Keep in refrigerator (not freezer) to store if unused and in a 50% state.

Thanks to the guys who gathered this info. Cheers Neil.

 

Thank you Neil,

A very informative post.

 

Sticky?

This is an excellent post. To the mods I would recommend posting it as a "Sticky" under the Hardware section.

 

You're welcome - sorry about Murrayfield. We watched the 6.15am (NZ time) replay and had brekky at the same time. Cheers Neil.

 

There was no surprises at Murrayfield, why are you apologising

What's that now, played 28 Won 0 Drawn 2 Lost 26?

Don't worry neil I'm not an egg chaser, I prefer the football and even though United's not doing great this season we've still got the Scottish Cup stored away in our trophy room (at least until May)

 

I played both forms of the ball game when I was younger. Our local Phoeniz football team got beaten at home last night - that's 3 losses in a row at home!

At least our Rugby League boys did the job on the Aussies and won the cup again. (4 Nations) PNG, England, Australia & NZ.

Crickets another talking point. Neil.

 

I think it's that sissy dance your lot do that put other teams off. Now if the Scots were allowed to wear their kilts and lift them before the game starts I bet they'd win more often

Anyway, well of topic now, start a thread in General Discussions or take it to PM before Arie hammers us

 

Your welcome. I generally store mine fully depleted as per HP so the battery can be calibrated when reinstalled. Does putting the battery in the refrigerator really work or is that just a myth? Then before reinstalling the refrigerated battery I guess you have to wait until its at room temperature correct?