Rescue Trucks To Fast-Charge Electric Cars

Still... this is one more feather OUT of the cap of the nay-sayers who have always claimed, "AAA can't bring me a plastic container of electrons on the side of the road!" Sure they can! wouldn't it be great if these things at least had bioD generators? How about a truckload of caps that are solar charged while the rig sits awaiting the call?

Really, it isn't that hard. If we can do tow trucks with gasoline on board, we can do energy trucks with electrons on board.

An 85% charge on 1 gallon of diesel. That is quite good! More efficient than a typical "range extender", and possibly more efficient than a Prius.

I just don't see the business model for these to succeed. They will have to charge a LOT of money for the charge in order to cover expenses let alone make a profit. This equipment is expensive! Then you have to figure that they won't be needed all that much anyway. EV drivers will adjust to the reduced range as compared to their previous ICE vehicles. I don't see how they can offer a service like this and not charge in the range of $200-$250 per charge. It would be much cheaper to just tow the car back to your home or a nearby chargepoint.

Personally, I wish they the J-1772 standard had been designed so that it would allow bi-directional flow. They you could just pull your EV up to someone else's and charge it a bit from yours enough to get to a charging station.
AC Propulsion EVs can put out Level 2 power levels but it should actually be possible to put out DC fast charge levels. Maybe the next or a future fast charge standard will allow this.
There would be no laws of physics broken if you drove your Leaf with an 80% SoC up to someone's with a 0% SoC, charged it for 10 minutes so yours had a 55% SoC and theirs had 20%, enough to get 20 miles to a charging station.

I'm just going to go with "ditto" on Benjamin's post! EVs aren't "there yet" because your Laptop battery is worn out?

With the small lithium polymer batteries (LiPoly or LiPo, as they are commonly referred to) we find in model airplanes, the thing that most commonly tends to kill them off is to completely discharge them. I assume that this is also true for lithium ion (Li-ion) formulas found in EVs. A well designed electronic speed controller (ESC) will initiate a low voltage cutoff to the model airplane motor, if the battery starts to run dangerously low. Its actually dangerous (chance of fire) to discharge a lithium battery all the way down to 0V.

The other thing that these little batteries don't like is to be charged at too high of an amperage or current setting. 1C - or charging at the same amperage setting as the battery - is typically recommended. Since many hobby chargers are designed to work with a very wide range of battery amperage ratings and cell count - not to mention different battery chemistry formulations - it's all too easy for the careless hobbyist to dial in the wrong settings on the charger and fry the battery with too much current.

I haven't heard about any ill effects of 100% charging, abasile, as I assume that this is what's going to happen just about any time a lithium battery-powered consumer device (cell phone, laptop) is going to be hooked up to the manufacturer-supplied charger that it was designed to work with.

The instructions on my new cell phone (which contains a 1000mAh Li-ion and came with a simple 0.7mAh charger without a "charge full" indicator light) basically says to charge until the phone's LCD indicates that its full, but not to leave the phone plugged into the charger for any longer than one week.

This is pretty much what I did with my last cell phone and the supplied Li-ion battery worked fine for the 5 years I owned it. Since consumers will typically use the charger that came with their cell phone or laptop, there is little danger of charging with too much current. The devices are also probably wired with low voltage cutoff, so they stop working long before the battery discharges into the danger zone. But nothing prevents a consumer from letting their Li-ion-powered device sit for months at a time and let the battery discharge beyond the point of no return.

If you're still with us, Marcin, take your laptop battery with you to the computer store, when you're ready to buy a new one. Not only will this make it easier for the person behind the counter to determine the proper replacement, they will be able to take it off your hands and (hopefully) dispose of it properly. NEVER simply put a lithium battery in the trash!

As far as 80% charging, this is what the model plane guys do with their LiPo packs, when putting them in storage during the non-flying months. They usually have to discharge the packs with a specialized device, like this one . . .

http://www.rcgroups.com/forums/showthread.php?t=1009719

. . . to ensure a controlled discharge (not too much and to keep all cells balanced) or using the discharge function built into many of the more advanced hobby chargers to obtain this 80% rate. But I have never heard of using the 80% mark as the most desired operating parameter.

@Benjamin Nead - "But I have never heard of using the 80% mark as the most desired operating parameter."

Nissan recommends charging the LEAF to only 80% unless you need the maximum possible range. In practice, we still don't know how much difference this will make in terms of battery capacity over the long haul. Also, an "80%" charge likely equates to lower than 80% SOC since the "usable" portion of the charge range is most likely about 84% of the total capacity.

I believe Tesla also recommends charging to only 80% most of the time.

From personal experience, I agree with what has been said about deep discharges. Nothing has seemed to hurt the capacity of laptop and cell phone batteries I've owned more than letting them drain all the way down.