[TriLUG] Thinkpad Batter\(y\|ies\)
Joseph Mack NA3T
jmack at wm7d.net
Thu Jul 1 21:44:20 EDT 2010
On Thu, 1 Jul 2010, Joel James Adamson wrote:
> A while ago I bought a Thinkpad 240
this is the little one? I have 3 of them. Provided they have
enough memory not to swap when you load a webpage, they're
great for travel. Unfortunately with the smaller kbd and the
different key layout, I have trouble going between it and my
other machines. Still it can't be beat for travel.
> Knowing nothing about laptops (this is my first), I'm
> unsure of the "gotchas" of buying a battery online.
First you need to know about batteries. Look on google for
"Li ion battery life". (I did find a place in Canada that
builds/tests/repairs (forget which) batteries and has a
whole heap of stuff about batteries, but I can't find it
The wikipedia page is a good start
o batteries don't like heat (I don't know how you can get
around this - when your laptop is on, it's hot. I guess you
shouldn't leave your laptop in the car during the day in
summer). I have some 10 yr old laptops that have been inside
the house all the time and they still work fine (I don't use
them a whole lot - they're too slow).
o at 100% charge, batteries loose 20% capacity/year. At 40%
charge they loose 2% a year (this is what Priuses and
solar/battery powered satellites rely on for battery life).
o batteries sitting on shelves loose capacity. Don't take
old stock. Presumably you want a store that holds a small
inventory and inserts batteries into cases almost on demand.
However I can't imagine anyone making up new 240 battery
packs anymore, so I expect yours will have sat on the shelf
for a while.
o expect a battery to last about 2 yrs.
o batteries are expensive and don't last long. Buy the
smallest number of batteries that you can live with.
o In your case get the extended battery. The regular is just
Here's who I bought my last 240 battery from (Dec 2006).
I haven't used the laptop for 2 yrs so I can't really tell
you how long the battery lasted. However I checked the three
240s earlier this yaer and they all had charge.
ebay, PAYPAL *SUNNBATTERY, ebcbattery, thinkpad 240,
3400mAH, FRU 02K6690 904-338-9619,
customerservice at ebcbattery.com, $28.95+$10.95 S&H
> 1) Are there any especially good (in any way) online vendors?
I've bought all over the place, in the early days not having
much of a clue what I was doing and without really being
able to tell how much capacity I should have and how much I
did have. I never got burned - I always got a usable
battery. Much of by batteries were from ebay. However I
found that the ebay 12V 7AH Pb batteries for UPSs lasted
about a year, while the equivalent batteries from Batteries
Plus (stores all over the place locally) last 2 yrs.
Except that Batteries Plus are more expensive than ebay,
they're better and the people are helpful. I buy all my UPS
batteries from Batteries Plus now.
Still if I had the choice of a laptop battery for $75 off
ebay and $150 from Batteries Plus I'd probably go with ebay.
I avoid buying batteries for laptops as I find that I want
to upgrade about when the battery is dead (I buy 5yr old
laptops for $200-400 and the battery cost is almost as much
as the replacement laptop). I try to stay close to power
plugs all the time (I carry a 3 way T-power adapter, so I
can plug into the wall when someone already has their laptop
Airports are terrible for getting power. I don't know where
they plug the vacuum cleaners in etc.
> 2) Is there anywhere locally I could buy one? They don't
> have anything compatible at the campus store
a 240 battery is a specialised item. Even Batteries Plus
would have to order it.
> 3) Anything to watch out for? I noticed one vendor offers
> a compatible battery for $19.95 labelled with
I expect it's an old battery pack with the dead cell(s)
replaced and the half alive ones still in there. Don't touch
it. All cells must be brand new.
Joseph Mack NA3T EME(B,D), FM05lw North Carolina
jmack (at) wm7d (dot) net - azimuthal equidistant map
generator at http://www.wm7d.net/azproj.shtml
Homepage http://www.austintek.com/ It's GNU/Linux!
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