I would have to dispute.Toorbough ULL-Zeveigh wrote:define 'some'!DrkAngel wrote:some dated 2004 still measured at better than 90% of oem rated capacity!increase cycle life, yes!DrkAngel wrote:Previous 2 year usable life might extend into 5-6 years and previous 6000 mile total might exceed 12-15 thousand miles.
calendar life, no!http://www.mpoweruk.com/life.htmBattery performance deteriorates over time whether the battery is used or not. This is known as "calendar fade". Performance allso deteriorates with usage and this is known as "cycle fade"http://en.wikipedia.org/wiki/Lithium_ir ... te_batteryAfter one year on the shelf, a LiFePO4 cell typically has approximately the same energy density as a LiCoO2 Li-ion cell, because of LFP's slower decline of energy density. Thereafter, LiFePO4 likely has a higher density.
1. 2004 & 2006 Lipo Lithium cobalt 4320mAh 6 packs measured at 3900mAh+ (used 7 & 9 year old packs were precisely capacity tested as test modules)
2. Used ~6 year old 10.8V 5200mAh Lenovo packs.
"Just ran a 18s capacity test.
Took about 4 hours with preliminary cell voltage monitoring - every 1/2 hour.
In the 3rd hour I began testing at 10 min intervals, then sooner.
The 36 2600mAh cells were left in 3s2p 6packs.
5200mAh oem rated
1 - 3300mAh+
5 - 3700mAh+
2 - 3800mAh+
2 - 4100mAh+
2 - 4300mAh+
4 - 4500mAh+
18 pairs thoroughly tested and accurately rated for capacity in 4 hours with minimal attention till the last hour."
3. NOS HP 10.8V 10,400mAh packs ~5 years old
6 - Sanyo cells - all discharged tested between 9000 - 10,000mah+
6- Samsung cells - all discharged tested between 8000 - 10,000mah
LiCoO2 has approximately 200% the energy density of LiFePO4.
According to your reasoning the LiCoO2 loses 50% capacity in one year! ... ?
..... OEM(new) ... 50%\year ....... Actual
1. 4320mAh ....... 9x = 8mAh ..... 4000mAh+
2. 5200mAh ....... 6x = 80mAh .... 4500mAh+
3. 10,400mAh ..... 5x = 325mAh ... 10,000mAh+
Something is very wrong with your "reasoning(?)"!
If LiCo lose 50% capacity, setting for 1 year ...
1. LiPo has 500x your estimated capacity
2. used Lenoveo has 56x your estimated capacity
3. NOS HP has 30x your estimated capacity
At the very minimum they should have lost 50% of their capacity, in the first year!
But even the 9 year old cells lost less than 10%.
I think you had better re-evaluate the reliability-veracity of your sources!
Partially retired Lipo pack (25.9V 25.92Ah Lico pack. 6500 miles - so far...)
Capacity loss was less than 50%, with ~daily use (300+ discharge-charge cycle) for a full year - 3000++ miles.