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  • Jay Bowman's December 5th Update  [View instapost]
    Whoa, so deep progress on those fronts (new gen/motor/tx) too...

    John be nimble, Jay be quick
    Both be burnin' dat candlestick!
    Dec 10, 2014. 01:35 PM | 7 Likes Like |Link to Comment
  • Jay Bowman's December 5th Update  [View instapost]
    Kudos John and Jay... it all sounds like an immense amount of coordination, redtape, and paperwork to have to slog/work through. To have kept making headway and completed many such milestones says a lot. Go ePower!
    Dec 8, 2014. 12:09 PM | 5 Likes Like |Link to Comment
  • Axion Power Concentrator 382: Nov. 22, 2014  [View instapost]
    Thought to take another look at this picture:


    And something I didn't notice before... when I saw it for the first time, I jumped to the conclusion that the smallest battery, the one on the right aft corner, must surely be simply a small flooded lead-acid battery dedicated solely to engine cranking--leading obviously to much speculation (not least on my part) as to what the larger L5 battery could be, as that one does look convincingly like some species of lead-acid battery, even to possibly being a PbC. This construction all kind of made sense to me, and lead to at least a possibility of a PbC being in there, if in fact that smaller battery was indeed simply a FLA there solely for cranking purposes. But now as I look at the picture again, and can't believe how I would have missed it, but with those higher-voltage orange leads connected to it, and the lack of obvious conventional LA terminals, it seems not at all a sure thing that that smaller battery is indeed lead acid. It seems rather to be connected to the larger Li-ion pack and could well be Li-ion itself. So I may have (and probably) had it all wrong: The lead-acid L5 battery may be the one that is the simple cranking battery while the smaller Li-ion is the one that is intended for hotel loads (while of course the larger Li-ion pack is devoted to traction). Obviously, in such a configuration, there wouldn't be much place for a PbC...
    Dec 1, 2014. 05:13 PM | 5 Likes Like |Link to Comment
  • Axion Power Concentrator 382: Nov. 22, 2014  [View instapost]
    On whatever timeline there be, many are quietly pulling for you...
    Nov 25, 2014. 02:09 AM | 7 Likes Like |Link to Comment
  • Axion Power Concentrator 381: Nov. 16, 2014  [View instapost]
    Iinde, Copy that, and I know you've made that point before. And I certainly don't challenge it. But note also that 60V is only exceeded if cell voltage is taken past 1.875 Volts, which from certain of the graphs, looks like around 90% SOC/SOE, so they might in the system just keep it always under that voltage by design, which also conveniently, would keep the battery in the region of low internal resistance too...

    But if it in fact is too much of a problem, then there's always the option of 5x 12V 30Hs or 30HTs, which would bring the total cell count to 30 vice 32 and would reduce the max voltage at 100% SOC that much more... maybe enough to work...
    Nov 23, 2014. 04:24 PM | 3 Likes Like |Link to Comment
  • Axion Power Concentrator 381: Nov. 16, 2014  [View instapost]
    IJSTM, that for any 48V system to make sense, and be worth anything, we've got to be talking about a certain amount of total energy and total power. And depending on the battery/chemistry chosen, that's going to mean a certain volume and a certain weight. There's no getting around it. For PbC it's going to be so many kilograms and so many litres no matter what, regardless of form factor. It's going to be bigger than a breadbox, it has to be, if it's going to do anything in the 48V realm.

    We've seen Kia's photos where they have three or four standard sized UB's in series. Why the heck move to a new low-volume (sales volume) single-battery 48V form factor? Just to be able to say you've shoehorned all the cells into one case?

    Makes no sense to me. I just think that if indeed anybody is going to use PbC in a 48v system that they're just going to use a simple string of 3 or 4, 12V 30Hs or 30HTs or 16V L5s to get there.

    Personally what makes most sense to me is 4 16V L5s in series-- that's a total of 32 PbC cells with a max fully charged voltage of say around ~67V (32 x 2.1) and a lower limit of ~38V (32 x 1.2). Such a string of four would weigh 84 Kg and take up about 50 liters of volume.

    But for that you could get at least 10 KW out of it (and into it) (at 5 min rate) with 2KWh of total energy (10Hr rate)...

    So again, if you want to stuff all 32 of those cells into one case, fine, but it's going to have to be one heckuva big case (~200lbs, ~12 gallons) in order to furnish the relevant power, so what's the point? Especially when doing so would preclude manufacturing such a form factor on existing battery lines.

    No, if they do this at all, they'll just use one of the standard form factors and hook 3 or 4 of them in series. It's what makes the most sense.
    Nov 23, 2014. 03:05 PM | 4 Likes Like |Link to Comment
  • Axion Power Concentrator 381: Nov. 16, 2014  [View instapost]
    Eastern Hemlock. With lead paint. Had a nice tang to it though. But what can I say, I'm a fan of the classics... ;)
    Nov 22, 2014. 02:15 AM | 10 Likes Like |Link to Comment
  • Axion Power Concentrator 381: Nov. 16, 2014  [View instapost]
    I just ate a pencil.
    Nov 22, 2014. 12:28 AM | 7 Likes Like |Link to Comment
  • Axion Power Concentrator 381: Nov. 16, 2014  [View instapost]
    With you RK. The 40cents number just didn't feel right to me either, though maybe they mean all-in with all the power-electronics, inverters, enclosures, maybe even the land etc? Might make more sense that way but still sounds expensive...
    Nov 19, 2014. 02:14 PM | 4 Likes Like |Link to Comment
  • Axion Power Concentrator 381: Nov. 16, 2014  [View instapost]
    This seems at least a bit provocative--in that the 30%-70% range is basically PbC's sweetspot on the charge-discharge vs internal resistance curve shown in the new manual:

    "The state-of-charge (SoC) of current lead-carbon batteries is typically maintained at between 30 and 50%, with the voltage and amperage meeting VDA requirements by not exceeding 54V at 150A when recovering joules of energy from vehicle deceleration (kinetic energy recovery) and exhaust gas energy recuperation (thermal energy recovery), also dropping not less than 38V at 180A when discharging energy for engine starting and torque assist. Advanced lead-carbon batteries for vehicles currently under development will be capable of operating in the 30 to 70% SoC range at 12.5kW."

    To my mind a string of four of Axion's 16V L5s could meet that duty pretty handily...
    Nov 19, 2014. 02:10 PM | 4 Likes Like |Link to Comment
  • Axion Power Concentrator 381: Nov. 16, 2014  [View instapost]
    If Columbus had never made it, it wouldn't have made him any less courageous or honorable. But we never would have heard of him either...
    Nov 18, 2014. 09:18 PM | 7 Likes Like |Link to Comment
  • Axion Power Concentrator 381: Nov. 16, 2014  [View instapost]
    A sad fact of life is that it seems no fun ever goes unpunished. Especially when it's a good deed to boot. But be that as it may, John, Jay, and ePower, Y'all just Keep on Truckin'!
    Nov 18, 2014. 09:14 PM | 9 Likes Like |Link to Comment
  • Tesla Motors preps solar rooftop initiative  [View news story]
    You're pushing a rock uphill SB4. The Knights of St. Elon are as intellectually impenetrable as a phalanx of star struck Beliebers...
    Nov 18, 2014. 03:41 PM | 1 Like Like |Link to Comment
  • Axion Power Concentrator 381: Nov. 16, 2014  [View instapost]
    "PbC needs to demonstrate a clear advantage over Li-ion in lifetime costs."

    Agreed. PbC definitely needs to differentiate itself from the various flavors of Li-ion with as much scope and clarity as is possible. Recall though John's experience from that recent trucking show--where some Li-ion reps came to him after his presentation trying to tout their batteries for ePower's application, and where once he laid out the performance demands, they said something to the effect of "we can't do that"... IIUC, it wasn't that "we can't do that as cheaply as Axion/PbC" but rather "we can't do that at all"... If indeed true (that lithium just can't) it's Kind of a big deal if you ask me.

    Anyway... I continue to think that the substantive reasons behind their answer need to be further explored and highlighted. Axion should make it its business to investigate, delineate, and publicize exactly how and in what areas Li-ion (at any price) is surpassed by PbC. That's a narrow space certainly, because Li-ion is obviously good for a lot of things, and spans quite an application range. But not everything. More needs to be made of this. Axion needs to do a better job of showing where PbC is not just cheaper, but better.
    Nov 17, 2014. 05:17 PM | 5 Likes Like |Link to Comment
  • Axion Power Concentrator 381: Nov. 16, 2014  [View instapost]
    I suspect DDG is a guy who watches the clock and calendar very keenly. Recall his opening of the CC: A full recitation and tick-tock of most of this year's action pieces and events. And he knows the clock started ticking for the next financing the day after this one closed.
    Nov 17, 2014. 04:11 PM | 5 Likes Like |Link to Comment