Battery Design Capacity vs Full Charge Capacity

[Leon]

If you Left Click on the Battery Maximizer Icon, select Battery Information, and look at both the Status Detail and Information Tabs, you will find the Battery Design Capacity (Mine says 47.52 Wh), and Full Charge Capacity (Mine says 43.3 Wh). Are yours similar?

My question are twofold:

1) Is this normal? I've had my T42 only a week. Don't know if this is what it was when new or if it's lost this much capacity in one week.

2) Under the IBM Battery Warranty, how low would the Full Charge Capacity have to go for replacement (or is there a better indicator of Battery health)?

[Daniel]

From what others have said, it's completely normal. My 6cell says the exact same thing as yours after 2 cycles. 43.3

[eriqesque]

How far did you drain the battery?
If you let it go below 10% or all the way to nothing then yes this is normal.
If you have not drained the battery then I would watch it, there is no set loss of capacity to have the battery replaced.
The more shallow discharges you do the better for the battey.
The more deep discharges actualy harm Li-Ion batteries.

[Hangfire]

My 3UU's battery would not charge over 98%... go figure.

[eriqesque]

There is a setting in the battery information to set the charging threshold.
I beleive this is only on the T42's

[awolfe63]

.

2) Under the IBM Battery Warranty, how low would the Full Charge Capacity have to go for replacement (or is there a better indicator of Battery health)?

There is a battery health tab in the battery monitor. If it shows red within the 1 year - then IBM will replace the battery. (At least they replaced mine).

[Flightvector]

Very deep discharges are not required to maintain battery life, and the batteries should not be kept at this state for a prolonged period. However, discharging from full use is not so harmful as much as battery age in itself. Storage at very high or low capacity or high temperatures as well as cycle count and age degrade Li-Ion batteries.

If the battery is used very often, then discharge should be kept at a minimum as this will be one of the primary factors of capacity loss. Going from one battery to another, and not fully discharging either one may help (like enriquesque says).

If the battery is used rarely, it does not pay to keep shallow cycles near 100% capacity, because storage age at high capacity is a primary aging factor here; then the battery should be kept at 40% at cool temperature until that occasional use is needed. But this is not saying that you should encourage long-term storage, because the battery will lose potential capacity over age; sparing use should be attempted.

[Nabeel]

I have the Sony, both remaining and charged are at 48.16. My old Sanyo wouldn't go back 98, this one so far always go upto 100.

[benz]

I have a Sanyo 9-cell, and at 98% I have remaining cap. 71.39, and full charge cap. 73.47.