Once I was nonetheless in elementary college and family flashlight batteries had been D-cells made utilizing carbon-zinc chemistry, a few of these D-cells had been set in cardboard tubes that enshrouded a zinc can as in Determine 1 under.
Determine 1 Carbon-zinc D-cell from sixty-plus years in the past the place the adverse put up is the zinc can and the constructive put up is a small tip. Supply: John Dunn
I keep in mind taking such cells aside to see what was inside and digging out a middle carbon core that related to the constructive put up tip. The adverse put up of the cell was the metallic can fabricated from zinc.
I suppose that these previous battery supplies weren’t threateningly poisonous, so I bought away unscathed for having executed that. Doing one thing like that right this moment, I hate to think about the chances.
Within the ensuing a long time, I’ve at all times naively assumed that the outer cans of D-cells, and different sized cells too, had been the adverse terminal however I’ve labored lo these a few years below a false assumption.
When two D-cells of a family flashlight lately gave out and I changed them, for completely no cause particularly, I took off the outer cowl of one of many used-up cells and bought fairly a shock, Determine 2.
Determine 2 In fashionable alkaline D-cells the can is the constructive finish of the cell. Supply: John Dunn
In these fashionable merchandise, the can is the constructive finish of the cell, not the adverse.
When it comes to the product’s objective, this distinction quantities to nothing vital, however merely discovering out this reality drove residence to me that a few of my lifelong assumptions shouldn’t be taken as immutable.
Science fiction author Robert Heinlein prefaced certainly one of his novels with the quote “Forgive him Caesar for he comes from a far place and believes the methods of his individuals to be pure regulation.”
Assume nothing. Query every part. (Many sources.)
John Dunn is an electronics marketing consultant, and a graduate of The Polytechnic Institute of Brooklyn (BSEE) and of New York College (MSEE).
Associated Content material
- When is a “good-enough” battery adequate?
- D-cell collapse
- The battery query I actually dread
- What’s your battery shelf-life expertise?
- Don’t ignore the necessity for small, low-capacity batteries
<!–
VIDEO AD
–>
<!–
div-gpt-ad-inread
–>
googletag.cmd.push(operate() { googletag.show(‘div-gpt-ad-inread’); });
googletag.cmd.push(operate() { googletag.show(‘div-gpt-ad-native’); });
–>
The put up Assume nothing. Query every part. appeared first on EDN.
