Laptop Battery life

stupideejay_2

Hello,
I've got a Samsung Laptop running an i3 processor etc. The Laptop is only 3 months old. The battery charge is set for 80% to preserve the life of the battery. Great idea but I'm only getting about 1-1 1/2 hours usage. When the battery gets to about 50% the time drops dramatically and then needs to be recharged. I use it mainly for surfing. Does anybody else have the same problem. It was bought from Currys.
Thanks for reading

Wywth

stupideejay wrote: »

Hello,
I've got a Samsung Laptop running an i3 processor etc. The Laptop is only 3 months old. The battery charge is set for 80% to preserve the life of the battery. Great idea but I'm only getting about 1-1 1/2 hours usage. When the battery gets to about 50% the time drops dramatically and then needs to be recharged. I use it mainly for surfing. Does anybody else have the same problem. It was bought from Currys.
Thanks for reading

Deep cycle it a few times from empty to fully charged
If it doesn't recover, you'll have to get a new one.

SCO

Have a Dell, only get about 1-1.5 hours in total.

InsideInsurance

Have Apple, get around 4-5 hours

First of all, what is supposed to be the battery life for the laptop and is there a statement of what this represents (eg my laptops advertised battery life says it is based on wireless web browsing with 50% brightness)

Secondly, even if you are just web browsing what applications/ processes do you have running in the background as these all take up CPU/ RAM too which equates to power.

Thirdly, what is your screen brightness setting at?

Magenta

SCO wrote: »

Have a Dell, only get about 1-1.5 hours in total.

Same here.

SCO

Magenta wrote: »

Same here.

They do seem to be one of the worst for battery life.

InsideInsurance

SCO wrote: »

They do seem to be one of the worst for battery life.

They conveniently also sell the bigger batteries too. My work laptop is a dell with the extended battery and I do normally get at least half a day (c4 hours) out of it

S0litaire

Under "ideal" conditions laptop batteries should last between 3-5 years...

In reality I've never had a laptop battery last longer than 24 months! But I tend to use laptops as a permanent/fixed desktop computer rather than a portable one! that tends to kill battery life!!

libra10

I have a 2.5 year old Sony Vaio and still get around 1.5 hours power from the battery.

The laptop is used a great deal, and I was advised to allow the battery to discharge daily to prolong battery life.

It certainly seems to have worked!

gjchester

Wywth wrote: »

Deep cycle it a few times from empty to fully charged

libra10 wrote: »

I was advised to allow the battery to discharge daily to prolong battery life

Lithium ion batteries do not suffer from memory effect as nicads used to (NiMH didnt either) and due to the chemistry if you did deep discharge them (which means below about 2.6v a cell) then the battery is likely to suffer an irreversible chemical change and you will be buying a new battery. Drawing them below that voltage also increases the risk they will react badly with results from overheating, ballooning up, or if really mistreated exploding.

The current best advice on lithium batteries is to keep them charged and never leave them in a discharged state for long. A day or so is fine (the device will shutdown long before the lower voltage limit is hit to give some protection so you can't really deep discharge them) but don't ever leave them flat for more than a few days. All devices draw some current from a battery when off. And the longer you leave it flat the greater the chance you take the battery below that critical lower voltage.

booler

From Wikipedia ...

If overheated or overcharged, Li-ion batteries may suffer thermal runaway and cell rupture. In extreme cases this can lead to combustion. Deep discharge may short-circuit the cell, in which case recharging would be unsafe.

To reduce these risks, Lithium-ion battery packs contain fail-safe circuitry that shuts down the battery when its voltage is outside the safe range of 3–4.2 V per cell. When stored for long periods the small current draw of the protection circuitry itself may drain the battery below its shut down voltage; normal chargers are then ineffective. Many types of lithium-ion cell cannot be charged safely below 0 °C.


Other safety features are required in each cell:[35]

• Shut-down separator (for overtemperature)
• Tear-away tab (for internal pressure)
• Vent (pressure relief)
• Thermal interrupt (overcurrent/overcharging)

These devices occupy useful space inside the cells, add additional points of failure and irreversibly disable the cell when activated. They are required because the anode produces heat during use, while the cathode may produce oxygen.

These devices and improved electrode designs reduce/eliminate the risk of fire or explosion. Further, these features increase costs compared to nickel metal hydride batteries, which require only a hydrogen/oxygen recombination device (preventing damage due to mild overcharging) and a back-up pressure valve.

These safety issues present a problem for large scale application of such cells in Electric Vehicles; A dramatic decrease in the failure rate is necessary.