I have no experience buying a laptop battery replacement. How do I confidently buy one?

I have a Lenovo Thinkpad T400. Currently with, I think, a 6-cell pack. Sanyo 93P5030.

I browsed the web. I found people selling packs for $20 or less. I get the feeling these might me "too good to be true" deals, with people refurbishing the packs by replacing a single cell rather than all cells, which means the pack might last a couple of years or a couple of weeks.

Thanks for any advice.

My experience. I buy at Amazon. Replaced batteries in my Lenovo T61, Asus N73S, Acer something and Compaq something. The latter two over 10 years old.

The battery replacement in the Lenovo lasted longer than the Lenovo itself, about 2 years.

In the ASUS, I am on the 3rd battery replacement in 2 years. I so I consider the batteries as consumables. The problem is the battery dies at once and completely. It is not that it gradually looses capacity. When it is still functional, battery life is decent. Not worse than the original.

The other two laptops are seldom used, but the batteries still work.

I am not sure these are refurbished batteries. The housing is new, it has not been opened before. I assume it is impossible to open without leaving traces.

So currently for the Asus I make sure I always have a spare battery on the shelve. It is correct it comes at about $20.

It is a good question whether I would prefer a battery 3 times as expensive if the lifetime were 3 times as long. Probably not, because the $20 batteries give me full battery running time every 9 months.

jlinkels

You might be very interested in this talk from LCA earlier in the year. I happened to be there and found it amazing.

I understand from various techie podcasts--it's been a while so I can't remember which ones precisely--that there are dubious fly-by-night outfits who make money by selling used laptop batteries from recycled laptops while claiming they are new, generally via auction sites.

If you are not buying from the manufacturer, be careful to vet the source.

I don't know of a fool proof way to get a replacement. I've ordered them from many places.

The only way that may be rather fool proof is to go to a local store like a battery shop. They may be able to provide a product and you have a place to go back to directly. They tend to cost a lot more from the local battery chain store.

Only buy from a large well-respected supplier whether you are buying refurbished or new. Batteries tend to be one of those things that you only get what you pay for, but sometimes can get burned if the seller is not reputable.

That's a normal function of lithium battery chemistry, whether lithium-ion or lithium-polymer. Unlike alkaline batteries, which gradually lose capacity, lithium batteries maintain full capacity output until they're exhausted.....then die suddenly. Literally overnight, in many cases.

I used to work for a local security company, and one of the firms we covered was a company called Vinten Broadcast in Bury St. Edmunds, Suffolk, here in the UK.

http://www.vinten.com/en

They have an enviable reputation globally as manufacturers of TV studio camera stands, which are used world-wide. They also supply an incredible range of battery packs for outside broadcast units, and were one of the very first firms in the UK to embrace the then relatively new lithium technology; they could see the potential, even 25 years ago. And even right at the beginning of lithium battery uptake, they were among the first to supply 'intelligent' chargers, that literally 'talked' to the batteries to find out what they needed. Quite amazing stuff.

I got talking to their night-shift manager one evening, and he gave me a thorough run-down of how lithium battery technology worked.....so I know a thing or three about it.


Mike.

The last time I tried to buy a replacement battery, it cost more than the laptop. Just keep it simple and get a UPS or other power cell thing plus a little circuitry to make it match your laptops plug. Lots of OTS things now with 110V and normal (for US anyway) plug sockets. Lots of usb outputting battery type things at every gas station these days. I prefer things that I can take with me for my "next" laptop. Then again most of my laptops are cheaper than a speeding ticket, and if I need more battery life, I buy another laptop. Laptop batteries tend to last about 3 years IMO. So don't buy used, it might have half the expected life, and die shortly after purchase (or before).