Hi All,

So are you saying that leaving the batteries on at all time wont jeopardize the life of G74SX batteries? Please advice
Thx in advance

gg31hh wrote:
Hi All,

So are you saying that leaving the batteries on at all time wont jeopardize the life of G74SX batteries? Please advice
Thx in advance

Correct, the laptop manages the battery and isn't just always charging it even when fully charged. In fact, letting the laptop control the battery charge by doing small charge/discharge cycles (Letting battery level drop to, say, 95% and then charging back to 100%) will extend the life of the battery and allow for more charge/discharge cycles compared to running the battery down to less than 50% before charging it back up.

Also, removing a fully-charged laptop Li-Ion battery and putting it into storage will cause it to lose total capacity by about 20% per year. If you're going to store a Li-Ion battery it should be discharged to 40% of capacity first. By doing this you only lose about 4% of capacity per year.

The short of it is leaving the battery in the laptop and leaving the laptop plugged in will be the least stressful on the battery and allow it to last the longest compared to removing it and throwing it in the closet or desk drawer.

Yahooligan wrote:
Correct, the laptop manages the battery and isn't just always charging it even when fully charged. In fact, letting the laptop control the battery charge by doing small charge/discharge cycles (Letting battery level drop to, say, 95% and then charging back to 100%) will extend the life of the battery and allow for more charge/discharge cycles compared to running the battery down to less than 50% before charging it back up.

Also, removing a fully-charged laptop Li-Ion battery and putting it into storage will cause it to lose total capacity by about 20% per year. If you're going to store a Li-Ion battery it should be discharged to 40% of capacity first. By doing this you only lose about 4% of capacity per year.


The short of it is leaving the battery in the laptop and leaving the laptop plugged in will be the least stressful on the battery and allow it to last the longest compared to removing it and throwing it in the closet or desk drawer.

Thank you. You have very well answer all my years of Laptop batteries dilemma.
I was bought out from the concept of " discharge all the power or you will effect the batteries memory"

I guess the technology of Computer batteries evolve from my olden day understanding

gg31hh wrote:
Thank you. You have very well answer all my years of Laptop batteries dilemma.
I was bought out from the concept of " discharge all the power or you will effect the batteries memory"

I guess the technology of Computer batteries evolve from my olden day understanding

Indeed, laptop batteries these days don't have memory like the old-school Ni-Cd batteries. Lithium-Ion batteries, like our G74s use, have no memory. Their life varies based on temperature, depth of discharge, and total charge/discharge cycles.

For example, discharging a Li-Ion battery "100%" every time will reduce the useful battery life to 500 cycles. Only discharging the battery to 50% increases the life to 1500 cycles, and so on. Less stress on the battery gives a longer life in terms of cycles.

Yahooligan wrote:
Indeed, laptop batteries these days don't have memory like the old-school Ni-Cd batteries. Lithium-Ion batteries, like our G74s use, have no memory. Their life varies based on temperature, depth of discharge, and total charge/discharge cycles.

For example, discharging a Li-Ion battery "100%" every time will reduce the useful battery life to 500 cycles. Only discharging the battery to 50% increases the life to 1500 cycles, and so on. Less stress on the battery gives a longer life in terms of cycles.

I see. It is interesting what people says when you google "extending batteries life" . But I thank you for your clear explanation.

So to be clear, It is best not to empty all the power from batteries but to let it fluctuate between 100% ~ 50%?

gg31hh wrote:
I see. It is interesting what people says when you google "extending batteries life" . But I thank you for your clear explanation.

So to be clear, It is best not to empty all the power from batteries but to let it fluctuate between 100% ~ 50%?

That's correct. Repeated deep discharges consume more of the battery and reduce life compared to shorter, shallower discharges. The example of the 100% vs 50% depth of discharge is a perfect example. If you only get 500 cycles out of a battery with 100% discharge every time and you get 1500 if you only discharge to 50% of capacity that's an increase in battery life of 1.5x/150%. Every time a battery is discharged part of it "dies" and will never hold a charge again.

A tool that's pretty handy for multiple aspects of PCs is "HWiNFO" (HWiNFO64 for 64-bit users like us). This gives TONS of info on the hardware it detects in your system, one of which is the battery. It tells you stated capacity, actual capacity, wear level (% degradation from factory spec), etc.

For mine it says the following.

Device Name: G74--52
Manufacturer Name: ASUSTek
Serial Number:
Unique ID: ASUSTekG74--52
Chemistry:
Designed Capacity: 78000 mWh
Full Charged Capacity: 77790 mWh
Wear Level: 0.3 %

Current Power Status
Power Status: On AC Power
Current Capacity: 77415 mWh (99.5 %)
Current Voltage: 16.720 V

Thanks everyone for detail description.