Michael Ross via EV wrote:
1C huh? That is not stressful at all and only a truly sh#t cell would have much trouble with that.
Ah, but that is heavily dependent on the kind of cell you are testing. There are many types of cells for which a 1C rate is a relatively fast discharge.
Also, 1C is a pretty reasonable rate for a lot of applications; things that you want to work for about an hour on a charge. Even some EVs are close to this; a golf cart or EV with a range under 100 miles discharges its batteries at about this rate. Many things like phones and laptops have even lower discharge rates.
We need standards, so there are at least *some* benchmarks to use as a basis to compare claims. Without them, all we have are manufacturer's claims, which are mostly invented by Marketing.
You said: "You need some test that is uniform for all manufacturers." I must disagree. This is the thinking that has us many decades along the way with no good way to compare battery cells.
On the contrary. We *have* had standard comparison tests for batteries for many decades. They are well established for most types of batteries... except lithium. It's the "new kid on the block", and so far, the manufacturers haven't seen fit to play by the rules.
The problem is you can't really compare batteries based on some simple criteria. If you dig into the Dalhousie research, you can see that the more complete and useful picture has a lot of detail. Medtronic and Tesla are two for the larger contributors to proprietary research. Both wanted to do a lot more than simply compete with existing tech.
Of course! That's always been true. Anyone who really cares about battery performance will do their own testing, tailored to their specific requirements. And they won't share that data with competitors!
But we still need standard testing for "the rest of us". Individuals and small manufacturers need *some* way to compare cells, and pick the ones that are at least reasonable for their applications.
I think maybe the testing protocols should be developed with a lot less input from the manufacturers. Fox guarding the henhouse and all that.
Yes. In general, earlier battery standard tests were devised by people like BCI (Battery Council International). It was a consortium funded by battery *users*, to combat the rampant deception in battery manufacturer specifications.
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