I didn't think of the weight, so these are all interesting comments to read. I guess those designing the new and improved batteries and car manufacturers will have to work around this somehow in their new designs.
OK on Bolder not having made the "D" cells, but somebody made them quite a while back, probably much more than ten years back. I know that presently Optima makes the larger batteries, the 12 volt ones, which offer impressive performance but are not electrically interchangable with the flooded cell battery devices, even though they fit mechanically. I think that the cells I saw may have been available back in the 1970's as a matter of fact.
I can't imagine a 1-man portable railgun, but certainly a small EBW detonator pack. That technology is something that I first read about before then, probably in the sixties, although my recollection of dates is fuzzy.
Bolder never made a D size version. We had a " superwind " version prototype for a military application designed to be belt worn. It was roughly twice the diameter of a 12 GA shotgun shell and designed for high current pulse military devices ( think about a man portable railgun or high energy output laser from DARPA ).
Both the cells had screw thread ternimals and we later experimented with spot welded braids ( you could even use the cell to create the spot welds; just charge it up, put the cell and braid in a fixture and pull a lever. Instant weld! ) and found a braid connection was cheaper and more reliable.
O.T., I think that I recall reading about those lead-based "D" size cells, and I even had a flashlight that used them. It only lasted about 15 years and lots of cycles and now it won't charge any more. And I am not aware of any current seller of those cells.
We did have an application that used 100 amps from the rectangular 7.2 AH gell cell. IT would run four "helicopter floodlights" and two film cameras in a crash vehicle. IT had to run the cameras long enough to spin up to speed, and the four lights, for 30 to 40 seconds, which the crash was typically 35 seconds after the turn-on.
Battery life was not great, but it was cost effective.
Tecochip, the most common failure in Chrysler starter motors is the rear sleeve bearing. In some other brands the brushes fail first, or else dirt gets in and the coomutator wears down rapidly. The other starter-related failure is broken teeth, either on the starter or the mating ring gear. Chrysler has had a quality problem with their starter motor bearings for many years. It may be fixed by now, my data is a few years old. Of course, new motors seldom fail, except for when the sleeve bearing does not get any lubrication at assembly.
On brush type servomotors the brushes are prone to wear out, the second common failure seems to be winding burning due to overheating. On brushless servomotors it is more likely to be the hall pickups or the bearings.
On industrial induction motorsit seems to be bearings or insulation punch-through, both failures more common on motors driven by inverter type drives. Otherwise it seems to be overheating failures caused by assorted types of dirt.
Yet lead seems to be doing fine in these series packs you speak of. As long as matched , made in the same batch, not murdered by bad charging, run dead and left that way, they have long and useful lives even many cells long.
Then to say lithium is the cure is rather rich as all the electronics needed just to keep Li alive kinda disproves your points. It will in the long run but not yet.
A 12vdc nom lithium battery has 4 cells, not 3. 3 cells loaded would be around 10vdc, not good enough.
Not sure what you mean by lithiums don't have the current capability as many do as it has the current that was designed in, just like lead batteries. Some for high power, some not so much. A123 as an example.
I do agree a good 36vdc nom lead pack, called 42vdc for some reason, with large cell interconnects which is what gives high power in both chemistries can easily do start/stop including runing the A/C if designed right.
Though you need to run them at under 80% charged during this cycling for lead, they really like being used and charge them to 110% at least 1/wk.
The use of :"And its safety performance is well known and widely accepted." is rather disingenious here. Yes, the safety of a typical lead-acid 12v car battery is well know, ususally assumed to be pretty benign. (Athough I was lucky as a 12 year old, changing the battery in the old Case tractor. When I slipped with the wrench and the battery exploded, I wasn't doused with acid. My face was merely bruised by plastic & wax schrapnel. I found the wrench 20 foot away, driven halfway through the oak barn wall - rather than through me...)
We also know that lead-acid built into long series strings for high-power traction pack exhibits extreme cell-to-cell imbalance, thermal runaway during charging, and fires rivaling anything seen in li-ion. (Although perhaps without some of the chlorine byproducts featured by some li electrolyte chemistries.)
So yes, the "safety performance" is well known. A "12 volt" lithium battery typically requires only 3 cells, and is a pretty manageable critter. We need a little apples-and-apples compairison here.
What the Lithium "car battery" lacks is usually current capability. Lead-acid can do quite well here. Advanced designs such as Benny Jay's Horizon battery can manage in excess of 2500 amps working discharge. What we also learn from advanced lead-acid battery design is that the advanced batteries are very finicky creatures to maintain. They acheive their optimum promise only with highly specific charge regimes and at specific (elevated) charge temperatures.
Hmm... Starting to sound a lot like today's lithium-ion product.
Don't get me wrong. Start-stop is a great thing. The industry will probably work it out pretty well with lead-acid batteries.
Extrapolating this to the traction pack applications... Don't bet on it.
That is what they tell you but the real reason is for every little car is another bigger, more costly one they can't sell. Recently they are finally seeing the light but are not going to change fast.
Next light practical EV's cost little, For instance my Streamliners is little more than a golf cart's worth of materials, just designed far better. No real reason after the novelty is worn off my $40k Streamliners can't be made for $10k.
Also most don't know it most golf carts have a 60-100 mile range with street tires in the street.
And these they can't make much off of. So they won't build low tech EV's but as I say, give us onerweight, overpriced and overteched EV's to prevent them from becoming popular.
It's also why they lie about battery cost.
Do they ever mention tax payers paid the full cost of putting big auto's EV's into production with grants? Billions!! Fact is they have almost no money in these and almost all pure profit. So please excuse me if I don't feel sorry for them but pi33ed instead.
If they would build a decent EV then I wouldn't have to. But they won't so I will.
I agree with you, Contrarian, when you say "cheap and simple seems to have fallen out of favor these days." When I ask (and I've asked many times) why automakers can't make cheap, simple electric cars with lead-acid batteries, I'm always told two things: 1. Too little range; 2. The batteries take up too much space. Seems like there should be a market niche, however, for an electrically-powered "second" car that sells for a price that's significantly lower than the Nissan Leaf, which is already getting quite low. Lead-acid seemingly should be able to make that possible.
Festo's BionicKangaroo combines pneumatic and electrical drive technology, plus very precise controls and condition monitoring. Like a real kangaroo, the BionicKangaroo robot harvests the kinetic energy of each takeoff and immediately uses it to power the next jump.
Design News and Digi-Key presents: Creating & Testing Your First RTOS Application Using MQX, a crash course that will look at defining a project, selecting a target processor, blocking code, defining tasks, completing code, and debugging.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.