Could just be the battery, Li-ons deteriorate over time regardless of being used or not. Batteries generally last between 300-500 cycles. A cycle is any discharge and recharge. You will get the longest battery life draining battery down to 5% or less and then recharging. Since you seem to use the battery alot, are you constantly discharging and recharging? This will greatly reduce the life of your battery. If it is the battery, it will continue to get worse until you will only get minutes out of the battery rather than hours. As the cells inside deteriorate, the good, active cells discharge into them rather than powering your notebook. Electricity follows the path of least resistance. It could still be something else draining your battery but don't be surprised if you don't find anything. For people who use the battery constantly, one year of battery life is usually considered quite good.
"You will get the longest battery life draining battery down to 5% or less and then recharging."
This is NOT true for Li-Ion technology. In fact, Li-Ion batteries should never be deep discharged like that, as they will suffer immediate effects. When you read a Li-Ion battery spec that tells you its rated number of charge cycles, that's on the assumption that you recharge it at the 70% level (that is, only 30% used).
It is good to go through one or two full discharge cycles on a new brand new battery. Let it fully charge PLUS wait a few hours, then discharge, repeat. It is critical that the first charge be completed fully and then left for some time to fully charge.
Following my advice will not damage your battery. All Li-On batteries have microprocessors in them to control discharge and charging. This is what communicates with your laptop and gives it the percentage information to display on the taskbar. It is also what controls the recharge rate and shuts it off when it is fully charged, even when your notebook is turned off. When your battery is totally discharged, each cell still has 2.5V remaining in it. If the cell falls below this, this is when the damage will occur.
If left below this state for about 2 months, permanent damage will occur. The cell will no longer be able to accept a full charge, perhaps even no charge at all. That is why you should never leave a battery in a discharged state because they will self discharge at a rate of about 10% per month at room temps. If it falls below the 2.5V, damage will occur. When powering your notebook, the microprocessor will not let the battery discharge fall to that 2.5V mark. In fact, it will tell your notebook that it is out of power and it will shutdown well before it gets close to that mark. Therefore, it is impossible to damage your battery by running it down to 5% as at this mark you will still be way above the damage point.
If you don't use a battery very often, you can preserve it by discharging to 40-45% and putting it in the fridge at 35-40F. Let battery warm to room temp before using. Remove battery once a month, warm, recharge fully and then use down to the 40-45% mark and place back in fridge. If you use your battery more often,
this is where 2 will come in handy. Use one while the other is in the fridge and swap every other month.
I have an HP notebook with 3 year old batteries that still work, albeit for only an hour, but this is due to the batteries deteriorating on their own, which will happen and there is nothing to prevent it. The cold merely slows it down to a trickle.
I have done extensive research on these batteries and I agree with SwampNut on the way to treat a new battery, I have also read that. However, I have never read about battery companies assuming you will recharge a battery at the 70% mark. What would be the point of that? On my 8200, I would reach that point in about 30-40 minutes, hardly portable anymore.
You may follow whatever advice you choose, or do your own research. I will follow what I have said as I have had great success in doing so.
The battery won't be damaged by deep discharge in the sense of immediate problems. Maybe I should say that it puts excessive wear on the battery. A deep discharge is more wearing than a lighter one.
Go to batteryuniversity.com if you want to learn more than you ever wanted to know about batteries.
Yes that is an excellent article, I had come across that in my research before. I will say that I now agree with your last post in terms of stressing the battery. That is why it is best to have two batteries and swap them out every other month. Constant users should have 3 or 4 batteries and
follow the same advice. That way they can have 2 available all the time. In the real world, most people are not going to only use a third of their battery and then recharge it. They are going to do what everybody does, run it till it quits, recharge when they get the opportunity, and leave the battery in the notebook 90% of the time. Heat is the real destroyer of these batteries and leaving it in the notebook constantly, even when on AC is more harmfull than my method. Overcharging causes heat, which is why there are microprocessors in the battery pack. If overcharging was left unchecked, the battery will burst into flames and explode. It has already happened with some cell phone batteries. This is also why we may see some new technology in the near future. Part of the high cost of Li-On batteries is the liability issue and the cost of the circuitry and microprocessor to control it. These batteries are inherently dangerous. The technology has been around for almost a hundred years, but it wasn't until the early 90's that Sony made it commercially viable. That is also why I never leave a battery in my notebook overnight when it is plugged into AC. I believe my method makes a good compromise between optimum battery life and real world usage. Most people do not have the discipline to follow the guidelines for optimum battery life and are going to destroy it in 12-14 months anyway, so why not get the most out of it each time.
You can't always recharge at 70% or so, but it's just something to keep in mind. On an airplane with no seat power, I end up using it all. Why have a laptop if you're not going to use it. However after killing my first battery in 6 months, I realized that many times I ran it on battery when I didn't need to. Like sitting in a client meeting where I very well could take 15 seconds to plug it in, or at home watching TV, that sort of thing.
I'm with you 100% on heat. The laptop's heat is MUCH higher than the damage threshold for a charging battery. Laptop makers should be giving us external chargers for the batteries.
I do indeed use and charge the battery very often, almost everyday. That's why I bought the Centrino - because I need a long battery life. Do you think that since the battery no longer gives me even 4 hours, the 1 year guarantee on the battery can be applied so as to allow me to get a new one from Dell free?
HP replaced the battery I killed on my Pavilion which I had before the 8600. They even let me keep the old battery. I don't see why Dell wouldn't do the same.
viper11885
791 Posts
0
February 12th, 2004 20:00
Did you change anything like your brightness setting?? Inceasing the brightness of your screen can dramatically drop usage times.
Also, you may want to do a spyware scan on your hard drive. Could be that something is running in the background that is using up your cpu resources.
RedsB3
106 Posts
0
February 14th, 2004 21:00
SwampNut
220 Posts
0
February 15th, 2004 15:00
This is NOT true for Li-Ion technology. In fact, Li-Ion batteries should never be deep discharged like that, as they will suffer immediate effects. When you read a Li-Ion battery spec that tells you its rated number of charge cycles, that's on the assumption that you recharge it at the 70% level (that is, only 30% used).
It is good to go through one or two full discharge cycles on a new brand new battery. Let it fully charge PLUS wait a few hours, then discharge, repeat. It is critical that the first charge be completed fully and then left for some time to fully charge.
RedsB3
106 Posts
0
February 16th, 2004 01:00
Following my advice will not damage your battery. All Li-On batteries have microprocessors in them to control discharge and charging. This is what communicates with your laptop and gives it the percentage information to display on the taskbar. It is also what controls the recharge rate and shuts it off when it is fully charged, even when your notebook is turned off. When your battery is totally discharged, each cell still has 2.5V remaining in it. If the cell falls below this, this is when the damage will occur.
If left below this state for about 2 months, permanent damage will occur. The cell will no longer be able to accept a full charge, perhaps even no charge at all. That is why you should never leave a battery in a discharged state because they will self discharge at a rate of about 10% per month at room temps. If it falls below the 2.5V, damage will occur. When powering your notebook, the microprocessor will not let the battery discharge fall to that 2.5V mark. In fact, it will tell your notebook that it is out of power and it will shutdown well before it gets close to that mark. Therefore, it is impossible to damage your battery by running it down to 5% as at this mark you will still be way above the damage point.
If you don't use a battery very often, you can preserve it by discharging to 40-45% and putting it in the fridge at 35-40F. Let battery warm to room temp before using. Remove battery once a month, warm, recharge fully and then use down to the 40-45% mark and place back in fridge. If you use your battery more often,
this is where 2 will come in handy. Use one while the other is in the fridge and swap every other month.
I have an HP notebook with 3 year old batteries that still work, albeit for only an hour, but this is due to the batteries deteriorating on their own, which will happen and there is nothing to prevent it. The cold merely slows it down to a trickle.
I have done extensive research on these batteries and I agree with SwampNut on the way to treat a new battery, I have also read that. However, I have never read about battery companies assuming you will recharge a battery at the 70% mark. What would be the point of that? On my 8200, I would reach that point in about 30-40 minutes, hardly portable anymore.
You may follow whatever advice you choose, or do your own research. I will follow what I have said as I have had great success in doing so.
SwampNut
220 Posts
0
February 16th, 2004 02:00
Go to batteryuniversity.com if you want to learn more than you ever wanted to know about batteries.
RedsB3
106 Posts
0
February 16th, 2004 11:00
Yes that is an excellent article, I had come across that in my research before. I will say that I now agree with your last post in terms of stressing the battery. That is why it is best to have two batteries and swap them out every other month. Constant users should have 3 or 4 batteries and
follow the same advice. That way they can have 2 available all the time. In the real world, most people are not going to only use a third of their battery and then recharge it. They are going to do what everybody does, run it till it quits, recharge when they get the opportunity, and leave the battery in the notebook 90% of the time. Heat is the real destroyer of these batteries and leaving it in the notebook constantly, even when on AC is more harmfull than my method. Overcharging causes heat, which is why there are microprocessors in the battery pack. If overcharging was left unchecked, the battery will burst into flames and explode. It has already happened with some cell phone batteries. This is also why we may see some new technology in the near future. Part of the high cost of Li-On batteries is the liability issue and the cost of the circuitry and microprocessor to control it. These batteries are inherently dangerous. The technology has been around for almost a hundred years, but it wasn't until the early 90's that Sony made it commercially viable. That is also why I never leave a battery in my notebook overnight when it is plugged into AC. I believe my method makes a good compromise between optimum battery life and real world usage. Most people do not have the discipline to follow the guidelines for optimum battery life and are going to destroy it in 12-14 months anyway, so why not get the most out of it each time.
SwampNut
220 Posts
0
February 16th, 2004 13:00
I'm with you 100% on heat. The laptop's heat is MUCH higher than the damage threshold for a charging battery. Laptop makers should be giving us external chargers for the batteries.
richs_ca
2 Posts
0
February 17th, 2004 19:00
Thanks for all the interesting information.
I do indeed use and charge the battery very often, almost everyday. That's why I bought the Centrino - because I need a long battery life. Do you think that since the battery no longer gives me even 4 hours, the 1 year guarantee on the battery can be applied so as to allow me to get a new one from Dell free?
SwampNut
220 Posts
0
February 17th, 2004 20:00