Thinkpads Forum

The T410 or T510 6 cell batteries. Thanks, that's with the machine powered off.

I don't use my battery much and rarely let it get below 25% or 30% capacity and I've never timed the charging back to 100%. Never fully discharge your battery, that is not good for it and will shorten its overall lifespan.

If you want faster charges, buy the 90-Watt power adapter. I did and battery charging is noticeably faster. I've heard there is a 135-watt charger available too but I haven't looked around to see where it's available.

raydabruce wrote:I don't use my battery much and rarely let it get below 25% or 30% capacity and I've never timed the charging back to 100%. Never fully discharge your battery, that is not good for it and will shorten its overall lifespan.

If you want faster charges, buy the 90-Watt power adapter. I did and battery charging is noticeably faster. I've heard there is a 135-watt charger available too but I haven't looked around to see where it's available.

So doing a battery calibration is bad? (Where you discharge it all the way)
Also, is it better to wait until it's around 5% before charging or higher around 20?

The lithium ion chemistry can be charged at rate of 2C safely with a tapering off charging rate as the battery nears 90% SoC. That means most of the bulk charging is done in 30 minutes or so and it'll slowly charge the remaining %.

Your Thinkpad will take between 2-6 hours depending on several factors, the battery pack actually has a temperature sensor (I am not sure about this next statement, but I believe some of the older Thinkpad packs had multiple sensors on each cell,) to monitor their temperature during charge. They are part of controlling the charge rate.

Why this is done is for battery pack life, see the below link and that nice chart at the very bottom.

http://www.batteryuniversity.com/parttwo-34.htm

With the T410, most of the bulk charging is done within 2-3 hours and then it tapers off at the end.

LodenCorp wrote:So doing a battery calibration is bad? (Where you discharge it all the way)
Also, is it better to wait until it's around 5% before charging or higher around 20?

During a ThinkPad-managed battery calibration, it's not FULLY discharged. I was talking about taking it all the way down to zero. A battery engineer reports that COMPLETELY discharging a lithium-ion battery can cause copper crystal-like structures to develop in the fluid and this will shorten the battery's overall lifespan significantly. He recommends never discharging it below 15-20%. To me, the whole calibration thing is a waste of time because in my experience the "time remaining" varies so much anyway depending on your power settings and usage that "calibration" is pretty much pointless.

Windows, the Power Manager, and the battery's own integrated electronics are all struggling against each other to report different capacities, cycle counts, charge, etc. I quit worrying about it... too confusing and complicated.

Most of the time, my battery is in the refrigerator wrapped up in plastic to protect it from moisture and sitting there at 40% charge. This will extend its overall lifespan quite a bit. I take it out and charge it up once a month or so to keep it healthy (or if I'm going on a trip or will not have access to AC power). Mostly I use the laptop without the battery in it, but I use the 90-watt adapter so that my CPU won't be throttled back. (This has something to do with the laptop's internal power management which changes if the battery isn't present.) If you use it without the battery installed and with the 65-watt adapter, you can't get the CPU up to full speed.

I set my battery to charge at 40% to 45%, if I plan on going somewhere later, I have it charge to 90% a few hours or the night before. If I had to put the battery in the fridge, I would recommend using an air tight ziplock after discharging it to around 40-50% and throw in a few of those silica gel packets you find in shoeboxes and such (To prevent moisture buildup)

You know, I have no clue what you guys are even talking about. I'm just asking for a simple answer.

A simple question: Do I need to calibrate my battery when I get it?
and, What's the best percentage before charging the battery?

Well it would be very hard to tell someone that a car engine is a magical solid state steel box when you're a mechanical engineer who designs engines and appreciates the art and work going into them.

Only do a battery meter restart every 10-20 discharge cycles. I'd leave the battery charged at 50% to preserve battery life yet have a nice balance between easily recharged when you need to take your T410 somewhere (Read: Where you can set it to charge to 90% then unplug and go.)