Different types of D batteries

[crazychicken]

I bought an electric lantern, put 4 D batteries in it, and turned it on expecting to see a very bright light. The first thing I thought was " oh, must be dead batteries". So I got out the trusty multimeter and check all 4 and they read 1.5v as they should. I was puzzled. I went to the store and got some more, put them in, and it worked fine. I measured the new ones and they also measured 1.5v. I measured the current through a 50 ohm resistor with both types and they both read 32mA. After closer inspection, the new batteries are Energizer D size-E95 LR20-AM1-1.5V and the old ones are Panasonic UM-1NP 1.5V. The Energizers say alkaline and the Pansonics say "Super Heavy Duty".

I'm assuming for some reason the Panasonics can't provide enough current for what the light is looking for.

1) What is the difference between these batteries ( I know "super heavy duty" is something besides alkaline which makes the life shorter, but how does that affect current output?)

2) How can I test for the max current these two types can produce? I used a 50ohm resistor so I don't think I could really use a much smaller one.

Thanks!

David

 

[Rubycon]

Heavy duty types will have a higher internal impedance and thus not suited for high drain applications. The alkaline will provide best current output for a primary (non rechargeable cell). Nickel Cadmium and Nickel Metal Hydride secondary (rechargeable) cells will provide the best performance at high drain. Even though their initial terminal voltage is lower (1.2V typ) under high load the alkalines will dip to this and lower. Standard carbon zinc cells are no match for high draw applications and many devices such as camera flashguns will malfunction or have very long cycle times with these cells.