Martin, I expect that every Tesla battery pack does not only contain cells and BMS but also status info like the amount of kWh that it ever supplied, the amount that is was fast-charged, other important factors such as operational temperatures, any weak/failed battery cells (as detected by imbalances between sets of paralleled cells in the series string, or possibly by detection of failures at cell level) and so on. So, at the moment a pack is swapped, there will be a value associated with the old and the new pack. I get the impression though that battery swapping is essentially returning either your own (recharged) pack as soon as you get back and in the mean time you are (temporarily) using their as-good-as-new pack and if you do not swap your pack back, then you can purchase that new temp pack for a hefty fee. Even if the swapped-in packs are not new, I expect that most people either don't care about the pack (it must work to spec of Tesla will be required to fix it) or you will be able to pay or get the difference between the value of your removed pack and the swapped-in pack, based on the age (about of kWh delivered and amount of fast-charge) and the other relevant factors.
In theory, you can even allow a Tesla with a small battery swap in a large pack for a long drive as well as a Large-pack Tesla swap in a fully charged small pack if you don't need to go much farther but do not like to wait for a recharge, but like to pay a smaller fee for the smaller pack until you come back to pick up your own pack again on the way back. New technology can also be swapped in, since capacity and power are likely to only increase over time, so an existing Tesla will maybe not use all the possibilities of the newer packs, but enjoy larger capacity as a longer range and since the battery computers will be able to tell the Tesla what they are capable of, the Tesla should be able to use the capacity but not the power, comparable to mounting a much faster and larger harddrive in an old PC: the speed may not increase much (limited by the old PC hardware) but the larger capacity of the drive can usually be enjoyed fully (as long as you were not too short sighted when defining your old PC and I believe that there is little fear for short sightedness in the case of Tesla....) Regards, Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com Email: [email protected] Private: http://www.cvandewater.info Skype: cor_van_de_water Tel: +1 408 383 7626 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Martin WINLOW Sent: Saturday, June 22, 2013 1:50 AM To: Electric Vehicle Discussion List Subject: Re: [EVDL] EVLN: Tesla Parades EV Battery Swap Technology When I watched the video the thought occurred to me that unlike BeP, to provide the technology to do the swapping, all Tesla has to do is reproduce the already well-proven battery insertion robot technology used in their factory as - apparently - there is no whizzo clamping system etc - it just undoes the bolts used to bolt the battery into place in the factory. That alone (if true) will save a serious amount of money. My issue is this:- Would you, as the careful owner of a relatively low miles 85kW Model S be entirely happy to swap your cherished and pampered battery for Lord-knows-what at a 'Tesla Station'? I, too, hope Mr Musk has something clever in mind to make this idea work. I do like the 'fast or free' idea, though. On its own that might just swing it. MW On 21 Jun 2013, at 19:49, Chris Tromley wrote: > I have tremendous respect for Tesla, but I think they've taken a seriously > wrong turn here. Swapping has been debated ad nauseum. It's an enticing > concept, but there are far too many ways it can fail in the real world. > Elon better have something very clever up his sleeve or this will likely > turn into a very visible failure. Hopefully it just disappears quietly. > > Chris > On Jun 21, 2013 8:17 AM, "Cor van de Water" <[email protected]> wrote: > >> The Tesla video shows them swapping a Tesla pack on-stage in 90 secs >> flat >> from driving onto the swapping unit until driving off. >> >> While they swap the packs in 2 Teslas, they have a parallel video >> of someone filling his gas tank as fast as he could - which takes approx >> 4 minutes (at the fastest station they could find nearby), so they >> actually have to wait for him to complete the fillup after the second >> Tesla S has left the swapping station... >> >> The comment: now you can choose between free and fast. >> (The fast-charging of Tesla is free, the fast-swapping apparently costs >> about the same as a fillup - they show the end result of the fillup at >> $99 so that may be an indication of the price, I did not catch how much >> a swap actually is going to cost. >> >> http://www.teslamotors.com/batteryswap >> >> >> Cor van de Water > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20130622/07a9 9004/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
