John writes: “Myles, I have no idea in the world where you get the impression that I
'seem' to think that battery makers have not been innovating”.
Sorry, I must have misunderstood. I deduced this from your writing and this comment about “upper level corporate and sales people”: ”….The plain fact is, they hate innovation”. I stand corrected then.
“I have mentioned that in my opinion the battery technology will be driven by the EV industry. (so all the efforts to gain boat range might be moot
- just sit back and let the car guys do the work!).”
Battery technology is driven by manufactures trying to meet the needs of a lot of significant markets. While they have long recognized the needs of the “marine” environment and have made available “marine deep cycle” flooded lead acid batteries, it’ll be a cold day in hell when we find them innovating anything specific for the electric boater. Nor do we probably care. Even in the case of land EVs, other than the few cars that are running with NiMH batteries that were developed for specific use on the EV1 (and a few pickups), I can’t think of any batteries (until very recently) made since the 1920’s that were developed for the road-vehicle EV industry. Sure, there are pbA deep cycle “golf cart” batteries and others developed for and targeted for neighborhood electric vehicles, but the highest technology batteries out there today and used in the EV arena were developed for other purposes (A123 lithium batteries were developed for power tools; Dow/Kokam cells were developed and innovated for the R/C market for years). Lately, the relatively low cost lithium batteries being made in China and the largest of the Kokam cells are being directly developed and marketed for EV-scale use, but this is all fairly recent as I understand it.
So EV’s of all sorts have for years been dependent on adapting batteries that were developed for other purposes. From 1900-1923, there were many models of PbA and NiFe (Edison batteries) that were developed for and marketed specifically as EV batteries. I would guess that back then (and before) also, Elco and other electric boat makers were using these or other batteries not developed specifically for E-boats.
Now, as for increasing E-boat range---The deployed battery technology we now have is pretty good and reasonably affordable. If weight and volume are not big constraints but cost is, lead acid is probably your best choice. If cost is not a constraint, but you want range, there’s little reason to not go with one of the lithium battery solutions. At say, 560wh/n-mile (5kts) a 100-n-mile range is achievable with a 56kwh pack. Unfortunately, with lead, that’s over 3000# of batteries…however, with the lithium batteries available today, neither the weight, nor the volume required for a pack this size is the limitation for me. It’s just a cost-benefit issue. It’d cost some $16k or so for the cheaper lithium battery options to achieve this…short of that, a 50- or 25-mile range on electric with lithium batteries begins to look affordable to me. But in the meantime, my $20/battery used T105 pack and an EU2000i give me an electric-only range of about 10-miles ar 4kts and unlimited range at that speed with the generator.
-Myles
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