T40P question: how do i cycle the battery? where is the utility?

[nanyangview]

Sorry guys...T40P noobie here..where is the utility that lets u cycle the battery to get the max usage out of it? i can't seem to find it.

I ordered my t40p from Thinkpaddepot and those guys are GREAT!!

2 days shipping to canada

 

[eriqesque]

To the best of my knowledge there is no utility to cycle the battery.

 

[azazello]

You do not cycle the battery. You cycle NiCd and NiMH batteries. This is a Li-ion battery. Discharging below 10% and leaving it at low charge destroys it.

 

[ES135]

Dang -

I wish we could get some definitive and authoritative advice with regard to using and maintaining
this battrery...differing suggestions all over this board.

I did ask an IBM tech about this once, but I don't think this was his strong suite. If memory serves
me he basically said if you leave it in the laptop just make sure you use it in battery mode
ocassionally...Not real deep.

I'll ping a couple more techs to see if we can firm this issue up once and for all and will repost
a new thread in small form factor something like

"Here is how the IBM t40 9 cell and 6 cell battery should be maintained" .

 

[azazello]

You're right, there's a lot of confusion with regard to maintaining batteries since the procedures are different for different chemicals. A lot of technical support manuals and personnel offer plain wrong advice.

The authoritative advice with regard to using and maintaining a Li-ion battery (all T40 batteries are Li-ion) is:

Avoid discharging the battery to below about 10%. Especially avoid completely discharging the battery. Also avoid leaving it in discharged condition for prolonged periods of time. 3/4 to full charge is the optimal charge bracket for Li-ion battery longevity. This means whenever you use the battery, make the cycle as shallow as possible. This is in direct conflict with the notion of long battery life, which means that you shouldn't pay too much attention to these guidelines and just use the battery as you need. The battery is rated for about 300 full cycles, and it can withstand perhaps 4 times that if you only half-cycle it (i.e. 1000 or more 100%->50%->100% cycles). No special maintenance procedures (like deep cycle) are applicable to Li-ion batteries.

 

[azazello]

(I'm not fully sure about the 300 number, but it's not far from that.)

Also, leaving the laptop always plugged in will not harm a Li-ion battery. The charger protects it against overcharge, and full charge does not harm a Li-ion battery.

 

[OldSpooky]

You're right, there's a lot of confusion with regard to maintaining batteries since the procedures are different for different chemicals. A lot of technical support manuals and personnel offer plain wrong advice

Damn... The help menu for the IBM Battery Maximizer recommended that I discharge the battery to less than 3% once a month. From the battery tips section in the T40 help files:

Reconditioning your battery can increase the full charge capacity of your battery. It is recommended that you let the battery run to less than 3% at least once a month.

:| I've only cycled my battery down to 2% once, but now my battery software says the battery can only hold 43 Watt/hrs vs the rated 48 Watt/hrs. Did I just kill 5 Watt/hrs of capacity? Uh oh.