lithium-polymer vs Ion

[thescreensavers]

Its to my understanding that Polymer gives more energy Ion.

Apple products are powered by Polymer and they get great battery life.

I don't get why other companies dont get into polymer as the same amount of space will give you more juice?

 

[CurseTheSky]

http://en.wikipedia.org/wiki/Lithium-ion_polymer_battery

The advantages of Li-ion polymer over the lithium-ion design include potentially lower cost of manufacture, adaptability to a wide variety of packaging shapes, and ruggedness.

Since individual pouch cells have no strong metal casing, by themselves they are over 20% lighter than equivalent cylindrical cells.

A compelling advantage of Li-poly cells is that manufacturers can shape the battery almost however they please, which can be important to mobile phone manufacturers constantly working on smaller, thinner, and lighter phones.

When compared to the lithium-ion battery, Li-poly has a greater life cycle degradation rate. However, in recent years, manufacturers have been declaring upwards of 500 charge-discharge cycles before the capacity drops to 80% (see Sanyo). Another variant of Li-poly cells, the "thin film rechargeable lithium battery", has been shown to provide more than 10,000 cycles.

So basically, they're not superior to Li-ion in terms of charging / discharging or battery life, but they are lighter weight and can be more easily shaped to fit different space requirements. My Envy 14 has a Li-poly battery, I believe.

The main reason Macbooks tend to have superior battery life is because of OSX. They design the hardware around the operating system, and vice versa. Other manufacturers are designing their hardware for Windows and whatever else is thrown in with it, meaning they don't have as great of a fine-tuned control as Apple does.

 

[thescreensavers]

I thought for sure the the Capacity of Lithium-poly is better then Ion size for size?

 

[wirednuts]

even if they are better you are talking a negligible difference. lithium poly and lithium ion are often interchanged. wrongly so since they are different, but overall performance is about the same.

i like polys because you get more battery into the same space, plus the overall weight is lighter. problem is you usually need to add protection around the battery to make it safe (ask chevy)

 

[CurseTheSky]

I thought for sure the the Capacity of Lithium-poly is better then Ion size for size?

Physical size for physical size, Li-poly is better simply because the battery can be a different shape and size, helping it to "blend in" better with the device around it. Li-ion cells are round (sort of like AAA batteries), and as such the batteries must be made in certain shapes and sizes to accommodate the cells.

Actual charging capacities should be nearly identical. Manufacturers can just fit more Li-poly cells in a device because they're not as constrained by the size and shape of each cell.

 

[cbn]

http://www.dailytech.com/article.aspx?newsid=20578

Sounds like this battery tech is making its way into more affordable products. (If you call $699 affordable)

(Nice thin form factor built around Lithium Poly and mSATA SSD)

 

[Emulex]

my 2007 li-po macbook air has 80-90% of its original lifespan. my 2007 iphone 8gb 2G has 90% of its original lifespan.

using the proper charger and battery care (plus computer aid) clearly works with apple. keep in mind they don't charge as fast as my laptop which has lost most of its battery.

so 2hrs+ to recharge macbook air - unlike the pc.

 

[flensr]

li-po batteries can be extremely hazardous if abused or damaged. Attempting to charge a physically damaged li-po battery can cause it to ignite like a road flare of the same or larger size. The batteries can also be damaged by a poor charging design or by a damaged charger, leading to the same explosive results. Sometimes a li-po battery that is physically damaged can begin to slowly overheat until it hits a limit that changes the internal (damaged) structure, at which point it can spontaneously ignite and again burn like a road flare, even if it hasn't been charged since the damage occurred.

If you want more info on li-po battery hazards, visit any radio controlled model forum and browse through their electric power forums. Lots of stories about people who have had their electric model planes suffer what appeared to be mild damage after a hard landing or crash, and then had the battery burst into flames hours later or at some random time in the future when trying to charge the battery. I read about one guy who was using a battery that had been in a crash, and since the battery had no outward signs of damage he used it several times. Then without warning, it burst into flames during charging, after he'd run that pack through several charge/discharge cycles.

I stay away from li-po whenever possible, except for electric RC model aircraft where power/weight ratio is extremely important and worth the risk. Still, I charge my batteries either in the fireplace and inside a fire resistant containment bag, or in the same containment bag but in the garage well away from anything flammable.

 

[mwmorph]

Li-Ion versus Li-Poly are comparable technologies.

Li-Poly is actually slightly less efficient than Li-Ion. Ideal situations, a Li-Ion battery of X volume and mass of reactant will actually provide more w/hr than a Li-Poly battery of X volume and mass.

As for disadvantages mentioned, durability is a concern. Li-Ion have rigid metal shells. The fire, rupturing, etc are still possible just like a Li-Poly but it is more difficult due to the stronger casing protecting it. This can be negated by wrapping the Li-Poly in a strong external case and charging electronics but that would negate some of the weight savings in not having a metal case.

Also Li-Poly tends to be more expensive than Li-Ion, sometimes much more so per watt/hour.

What Li-Poly has as advantages is packaging. Because of flexible shape, it can be packaged in odd spaces more easily which can negate the w/l deficiency by packing more of the available volume with Li-Poly material.

 

[wirednuts]

and i want to add, i think all lithium batteries suck. theyre just glorified alkalines (different metals, but whatever)

i think the future is almost here though. carbon-nanotube supercapacitors. they will change the game. when compared to lithium batteries, you get about the same or a little more capacity (already, the sky is the limit on future capacities) , HALF the weight, recharge/discharge cycles starting at 10,000 times and possibly way more then that, charge times in the seconds, ability to fully discharge in less then a second, overall life cycles in the decades, and absolutely safe (and very green!).

automobiles are going to be the first to use them. we will ALL be driving electric cars soon (less then 15 years?). firefighters are excited because they can drain all the deadly voltage in a car instantly and safely. people will love the 90 second fill ups at the electric stations (your house), and big oil companies will go the way to tobacco. win-win-win-win-win etc....

the technology is already proven. mass-manufacturing is the only problem right now. cost isnt even the concern, all these things are is metal plates with carbon on them. but making them in large quantaties will require a bit more brilliant engineering.... although im very confident they will figure it out (they dont seem worried).