BATTERIES: peak current? continuous current? energy stored? Which brand gives highest continuous current?

Question

How come they only tell you the voltage?

Answer 1

A way to determine the capacity of a battery you need to know the internal R resistance.

You can determine the R by:

knowing R = V / I

Using a Voltmeter across the battery and adding a Resistive load until the Voltage starts to drop. At this point the internal Resistance = R load and the current is I = V / R.

The battery output is the Power in watts = V x I.

The larger the dry cell the more power capability.

Answer 2

I've checked a few brands web pages, and they never tell you the capacity of their batteries in amp-hours.

you have to guess, or measure, or (what they hope for) go by brand name.

Actually CU had reviews of batteries, where they measured their capacity...  you could probably dig that up.

Answer 3

you should be able to go to the brands web sites, I believe they run .05mA/hr of continious use.

Answer 4

Batteries are sold to the public. Technical data seems unavailable because the public buys based on the size and voltage, good marketing campaigns, stylish packaging and occasionally on price. About 1/2 of rechargeables report their capacity; the disposable ones rarely do.

Devices that use batteries, such as flashlights and toys actually are extensively engineered and tested. As noted below, considerable technical data is available to these guys, and you can find much of it on the Internet if you look hard enough.

The brands are typically fairly equivalent. Use capacity to compare, just make sure the method used is consistent.

A few professional suppliers publish the capacity of their batteries, on their sites or in their catalogs, like maybe Newark, Allied Electronics, etc.

Wiki has extensive battery information. See the links below, and investigate the links they reference, including other Wiki articles.

http://en.wikipedia.org/wiki/Alkaline_ba...

http://en.wikipedia.org/wiki/NiMH_batter...

http://en.wikipedia.org/wiki/D_battery

Major manufacturers/suppliers actually do provide data to engineers making products. They have the data on their websites, however, it is usually buried or on a separate technical website. Here's the top 3 US battery technical site/subdirectory:

http://data.energizer.com/

http://www.duracell.com/oem/primary/Alka...

http://www.rayovac.com/technical/specs.h...

And here's a professionally oriented site:

http://www.batteryholders.com/link.shtml

Answer 5

Because for consumer electronics, all you really need to know is the physical size and the voltage.

Any rechargeable battery will have a capacity on it, in ampere-hours (or milliamp-hours for smaller batteries).  The chemistry and design of the battery governs the allowable peak and continuous current.  For example, lead-acid starting batteries are designed to give very high currents for a short time, but a different design of lead acid trades off peak current for longer life in deep-cycle applications.

The nickel metal-hydride batteries made for RC cars are some of the highest continuous current batteries around.  Lithium-ion batteries are also not bad.  In primary batteries, alkaline and silver oxide batteries can deliver a high continuous current for their capacity.

The are many good web sites available for any particular chemistry of battery.

DK