Li-ion batteries

Wikipedia is our friend. It has a nice article on Li-Ion batteries. Various manufacturers also offer good information, for instance Panasonic.

Cheers!

Check the data sheet from the manufacturer. I think they do accelerated life testing at elevated temperature and loads. It is a ghastly business - see what they found out before trying it yourself.

You need more than the output specs to know how long it will Last. If you can contact the manufacturer you have to look at his composition. Lithium in these battery is not 100 % pur so you have to check for is purity an than the reactive they use. The life time will varries depending what is the use you're making out of it. usually battery life time is count in number of charges before loosing his efficiency and you have to remember that after 3 month and unused battery is starting to degrade itself because the materials inside are kind of fusing together so your battery will be less efficient. Temperature is a factor to consider to. Hope this help you a little.

First thing I would do is contact the manufacturer. They may be able to tell you an approximate Life cycle estimate (for given usage profiles). If you are using your batteries differently than the Manufacturer's standard usage, then you will have to use their life cycle information as a rough guideline.

Lithium Ion technology is a loose term, covering numerous types active materials inside the battery. You would need to know the specific type of materials used in your battery. There may be some data for Life-cycle already out there. You can also check with the National Renewable Energy Laboratory (NREL) at www.NREL.gov Here you can search for Lithium Ion Life and if you know what type of chemistry you have in your battery, you should be able to find some good information here.

Good Luck!

1: Ask for the material set:

LiFeCo is the common material set, danger, this can go flame up if over charged or over discharged, nature of the beast.

You will need to know the 10, 5, and 1 DQ rate. You want a battery system somewhere around 155 mA @ 10 DQ rate discharge. (not many get there).

LiFePO4 systems are more stable, but still in development.

Thanks so much, everyone. Everyone gave exactly the sort of information I was looking for.

All the best,

Bluezone

Regards

What's beauty in specifying capacity in WH instead of AH?

Who suggested using WH instead of AH? Personally, I've only seen AH for batteries.

Bluzone

Regards.

No body in this topic has sauggested in this post.

Dell Type C1295 for laptop d600 has "Capacity 53WH" on their product which seems to be nearly 4.5AH.

Thanks

While Ah is the most common measurement of Battery capacity, it is slightly inaccurate, as the amount of Ah you can put into a battery can vary a bit, depending on the current (A) used. With a Higher current, you will hit your voltage limits sooner, and not get as much energy into the battery. To totally "fill" a battery, often multiple current profiles will be used, to alleviate this problem. A more appropriate measurement of capacity is technically Wh, as it is the measurement of exactly how much energy is in the battery.

Having said that though, most of the time for common batteries, the charge profiles are very similar, so it can be reduced to an Ah rating & still be a valid comparison.

Thank you, Yosh, for the answer, and thank you, Haajee for asking your question. I didn't know that.

All the best, and enjoy the weekend!

Bluezone

Reply to:

YoshP for #9 & bluezone for #10

Thanks for good reply

I like to add that:

In one of my employers' Setup I had been working on Battery Assemblies in the era of Carbon-Zinc Battery-Assemling.

Complaint from End-users was that due to a small number of of bad cells whole assembly had to be un-useable.

Research people were unable to reduce the problem for Carbon-Zinc Battery-Assemling.

But on the advent of Ni-Cd batteries the Research people tried to resolve the same problem as in Carbon-Zinc Battery-Assemlies, because it was re-chareable and worked on the line:

A new problem was faced in Ni-Cd batteries; that bad cell(s) charged in reverse polarity & cannot be recovered;

a worse problem.

1. To group similar-capacity cells by testing "Constant-Power" tests designed-indigenously test setup.

2. To test Assemblies for at least 3 cycles of Charge-Discharge @ full-load before supply.

Results were well improved as well as the fame of the firm.

Refer to:

Cell Balancing

... In multi-cell batteries problems could arise from interactions between the cells caused by small differences in the characteristics of the individual cells making up the battery. Cell balancing is designed to equalise the charge on every cell in the pack and prevent individual cells from becoming over stressed thus prolonging the life of the battery. See Cell Balancing <http://www.mpoweruk.com/balancing.htm>

Some links of intrest:

http://electronic-components.globalspec.com/LearnMore/Electrical_Electronic_Components/Batteries/Lithium_Batteries" Primary lithium batteries provide long-term storage life and long operational life over a wide range of temperatures. Common types of a primary lithium battery include lithium sulfur dioxide batteries (Li/SO2), lithium thionyl chloride batteries (Li/SOCl2), lithium manganese dioxide batteries (LiMnO2), lithium carbon monofluoride (Li/(CF)n)batteries, lithium copper oxide batteries (LI/CuO), lithium iodine batteries(LiI2), and lithium anode reserve batteries (including lithium vanadium pentoxide, lithium thionyl chloride, and lithium sulfur dioxide styles).

Lithium batteries are available in many secondary rechargeable styles. Common types of secondary lithium batteries include lithium iron sulfide batteries (Li Fe Sx), lithium manganese titanium batteries (Li Mn Ti), and lithium polymer batteries. Secondary lithium batteries also include lithium-ion batteries such as lithium cobalt oxide batteries (Li Co O2), lithium nickel oxide batteries (Li Ni O2), and lithium manganese oxide batteries (Li Mn2 O4). Lithium-vanadium pentoxide batteries (Li V2 O5), lithium manganese dioxide batteries (Li Mn O2), and lithium titanium disulfide batteries (Li TiS2) are also available. "

Regards.

Thank, again, Haajee.

-Bluezone

It is diffcult to said the life time of a li-ion battery as this is totally depend how you use the battery in the period.

Normally, we would said how many cycles the battery can discharge and recharge. It would be 300-500 cycles for li-ion, if you have made these cycles in a month, then the life time would be a month, made in a year, the life time is a year. So, it is depend.