Apple looking to increase battery life with dense lithium battery cells
Apple is investigating techniques to increase the energy capacity of rechargeable lithium battery cells without increasing the size of the battery, allowing longer battery life in future devices.
The proposed invention is detailed in a new patent application published by the U.S. Patent and Trademark Office this week and discovered by AppleInsider. The filing, titled "Increasing Energy Density in Rechargeable Lithium Battery Cells," describes charging a battery using a "multi-step constant-current constant-voltage (CC-CV) charging technique."
The CC-CV charging technique would allow the thickness of the anode active material inside a battery cell to be increased in both "volumetric and gravimetric energy density." But while the density of the power capacity would be increased, the size of the battery, as well as its maximum charging time and minimum life cycle, would remain unchanged.
Apple's application notes that the conventional method for increasing the battery capacity, or ampere-hour (mAh), of a lithium-ion or lithium-polymer battery involves increasing the lengths of the anode and cathode current collectors, as well as their coating materials But increasing the area of current collectors results in lower volumetric energy density, and results in a larger battery.
"What is needed is a technique for increasing the energy capacity of a rechargeable lithium battery without increasing the size of the battery sell," the filing states.
Apple's application notes that the company intends to make battery cells smaller, allowing the "limited space available in portable electronic devices to be used more efficiently." The company noted it could use the space savings to add more features, or more battery capacity.
But one issue with employing the multi-step CC-CV charging technique is battery life can be significantly decreased depending on temperature. For example, using the same current-charge density at 10 degrees celsius will lower the cycle life "substantially" when compared to a higher temperature such as 45 degrees.
In addition, current-charge densities further reduce the battery's cycle life if it is at a higher state of charge, between 70 percent and 100 percent.
Apple's solution would reduce the charge currents for a mobile device when its battery is at a higher state of charge, or a lower temperature. This would avoid degradation in the cycle life of the battery, and potentially even increase it, without any required change in battery chemistry.
The multi-step charging technique would be compatible with the new battery design and would increase battery life by dynamically adjusting the rate of charge when the battery is at different states of charge, or different temperatures.
Apple's proposed invention revealed this week was first filed with the U.S. Patent and Trademark Office on Aug. 22, 2009. It is credited to Ramesh C. Bhardwaj and Taisup Hwang.
The proposed invention is detailed in a new patent application published by the U.S. Patent and Trademark Office this week and discovered by AppleInsider. The filing, titled "Increasing Energy Density in Rechargeable Lithium Battery Cells," describes charging a battery using a "multi-step constant-current constant-voltage (CC-CV) charging technique."
The CC-CV charging technique would allow the thickness of the anode active material inside a battery cell to be increased in both "volumetric and gravimetric energy density." But while the density of the power capacity would be increased, the size of the battery, as well as its maximum charging time and minimum life cycle, would remain unchanged.
Apple's application notes that the conventional method for increasing the battery capacity, or ampere-hour (mAh), of a lithium-ion or lithium-polymer battery involves increasing the lengths of the anode and cathode current collectors, as well as their coating materials But increasing the area of current collectors results in lower volumetric energy density, and results in a larger battery.
"What is needed is a technique for increasing the energy capacity of a rechargeable lithium battery without increasing the size of the battery sell," the filing states.
Apple's application notes that the company intends to make battery cells smaller, allowing the "limited space available in portable electronic devices to be used more efficiently." The company noted it could use the space savings to add more features, or more battery capacity.
But one issue with employing the multi-step CC-CV charging technique is battery life can be significantly decreased depending on temperature. For example, using the same current-charge density at 10 degrees celsius will lower the cycle life "substantially" when compared to a higher temperature such as 45 degrees.
In addition, current-charge densities further reduce the battery's cycle life if it is at a higher state of charge, between 70 percent and 100 percent.
Apple's solution would reduce the charge currents for a mobile device when its battery is at a higher state of charge, or a lower temperature. This would avoid degradation in the cycle life of the battery, and potentially even increase it, without any required change in battery chemistry.
The multi-step charging technique would be compatible with the new battery design and would increase battery life by dynamically adjusting the rate of charge when the battery is at different states of charge, or different temperatures.
Apple's proposed invention revealed this week was first filed with the U.S. Patent and Trademark Office on Aug. 22, 2009. It is credited to Ramesh C. Bhardwaj and Taisup Hwang.
Comments
You would think there time and money could be better spent elsewhere right now... the current MBP already last 8 hours or so..
Yeah... but wouldn't you like a MBP that weighs less?
You would think there time and money could be better spent elsewhere right now... the current MBP already last 8 hours or so..
With the new technology Apple can make a smaller battery last the same 8 hours.... Smaller, lighter, thinner. That is the objective for apples products.
You would think there time and money could be better spent elsewhere right now... the current MBP already last 8 hours or so..
With $60billion to spend I'd have to disagree, until battery life is >1week
You would think there time and money could be better spent elsewhere right now... the current MBP already last 8 hours or so..
I would disagree, the long term implications of smaller and longer lasting battery technology reaches far beyond the computer industry, think electric cars. This could be a whole other revenue source for apple.
You would think there time and money could be better spent elsewhere right now... the current MBP already last 8 hours or so..
Battery capacity has always been holding mobile electronics back. With better batteries, the MBP could be faster, smaller and/or lighter. Then there's smartphones...
I can't think of a better area to research.
You would think there time and money could be better spent elsewhere right now... the current MBP already last 8 hours or so..
How dare Apple spend R&D money on R&D. I mean they make one product that gets acceptable battery duration for me and that's all that counts. I don't care that they also make smaller devices like the Macbook Air, the iPod touch, the iPhone or even a rumored smaller iPhone that would really benefit from this sort of technological improvement.
Those bastards.
Seriously, for good or bad, there is nothing like hydrocarbons for energy density/transportation. Battery tech(for now) will be a slow incremental process of improvement.
May I suggest this article regarding 'tech breakthoughs or lack there of'. Food for thought.
http://isites.harvard.edu/fs/docs/ic...gy_Summary.pdf
You would think there time and money could be better spent elsewhere right now... the current MBP already last 8 hours or so..
I think this is more for the iPhone and MacBook Air.
With $60billion to spend I'd have to disagree, until battery life is >1week
That would be cool. I could go on vacation and leave my charger at home.
Think MagSafe connector.
Think LiquidMetal, this battery R&D.
That would be cool. I could go on vacation and leave my charger at home.
I'd rather have the life-time battery that they used in Small Soldiers.
I would disagree, the long term implications of smaller and longer lasting battery technology reaches far beyond the computer industry, think electric cars. This could be a whole other revenue source for apple.
Oh lord, I can't wait until the power companies all must give Apple 30% for the ability to sell us power to charge our cars.
Oh lord, I can't wait until the power companies all must give Apple 30% for the ability to sell us power to charge our cars.
That's only if the charging is being done via the App Store
How much of an increase is this over the current batteries? If they can have the same size battery and get 12 or 16 hours of life, I can see them doing just that. Look at all the PC laptops (cue cries that Apples are PCs) that try and compete with the MBP and get all of a couple of hours of battery life. This could put Apple's products even farther ahead, not to mention that they could use a smaller battery in the iPad if they wanted to make it lighter and keep about the same battery life. The MBA could only benefit from this as well.
I don't know enough to be able to evaluate the significance of this, but on the face of it I find it very interesting that Apple is doing R&D into battery technology rather than just relying on the battery producers to do it.
Yeah, that's the funny thing about people's attitude towards Apple in general, most people think Apple just uses off the shelf generic parts in their products. The fact is, a lot of the components used, Apple had a hand in designing and manufacturing. Apple works with OEMs to ensure those parts meet Apple's specifications.
Apple also invests a lot in manufacturing processes, techniques and materials, even though they aren't a manufacturing company.
Oh lord, I can't wait until the power companies all must give Apple 30% for the ability to sell us power to charge our cars.
And that ^, everyone, is how a troll responds to an article on improving battery life.
I don't know enough to be able to evaluate the significance of this, but on the face of it I find it very interesting that Apple is doing R&D into battery technology rather than just relying on the battery producers to do it.
I think the a more proper observation would be Apple doing the R&D for essentially everyone else.
Expect competitors to coincidentally adopt the new batteries after Apple perfects it.