Nissan Leaf ($25k, 100m Range, 100% Electric) VS. Chevy Volt?


#261

EV’s have reached the point where they’re fine in a 2 vehicle household where the EV can have daily commute duties and the 2nd car can handle the road trip duties. They’re not practical for a 1 car family unless you want a lot of hassle on long road trips. Even if you can find a supercharger you’re talking 20 minutes to go from dead to 50% and 40 minutes to go from dead to 80%. Compared to what, 3-4 minutes to go from empty to 100% full with gasoline with a gas station at every highway exit and rest area?


#262

Related:


#263

I am fine with the technology going this route, but I’ll continue buying used gasoline cars until they come up closer to the standards I’m needing.
The problem with plugging it in every night even if its not needed is that it kills batteries quicker. Please correct me if I’m wrong but with modern technology with batteries, usually the best results for longevity is to run them from full to almost dead, recharge the full amount and repeat. If you recharge batteries with 2/3 life left, its going to kill the life of the battery quicker. With how expensive those batteries are, its a pretty large purchase to replace.


#264

I’m curious if in the future we will find more Tesla style ideas. Instead of a gas station you have a battery swap station. If every manufacture could get behind a set of batteries in the future. (3-4 different manufactures so its not monopolized) which I’d figure they wouldn’t want to team up that way, but I could see them having recharge stations/battery swap stations where they can hold each manufactured battery for a quick and easy swap.

YEARS FROM NOW. lol


#265

Pretty sure this is old and applied to batteries from like 15 years ago. And even then I still recharged at 2/3 because lithium ion batteries only lasted 3 years or so anyway, lol.

@RedGoober4Life answered this a while ago I think.


#266

I’m being summoned! Yes, full cycling was best for Nickel Cadmium batteries that had a weird “memory” issue where the voltage and state of charge relationship became less reliable after a few partial cycles (voltage is often the measurement of choice for state of charge with many battery chemistries). You could actually recover a nickel cadmium (and nickel metal hydride for that matter) battery by doing several full charge-discharge cycles (and at bottom of discharge, allowing the battery to rest open circuit, and applying discharge circuit again for a few rest-discharge cycles). There’s also this weird pulse-overcharge that some nickel metal hydride cars do for battery life, but it’s only about once a year… but that’s some weird shit.

Lithium-ion doesn’t need to be cycled fully, though cycling is the primary cause of degradation of lithium ion batteries. It is true that a smaller cycling window (i.e. the middle 40 % versus the middle 70 %) is better for life, which is why some manufacturers let the customer decide what percentage is top of charge (i.e. 80 % versus 95 %). A lot more degradation happens near top of charge than bottom of charge, which is why charging current is tapered at the top. A lower top of charge also helps with another factor with durability – “shelf life” at open circuit at high states of charge. Lithium-ion batteries degrade just sitting around at high voltages and high temperatures…

I’d say that topping up often is probably less taxing on the battery than fully cycling, though. Degradation due to cycling > degradation due to aging at high voltage. The battery management software should taper current accordingly…

With all that in mind, most manufacturers have oversized their batteries so the consumer won’t observe sizeable battery degradation. The Volt is a good example of this – that pack is huge and underutilized. Tesla seems to do a good job with this too (and they should, their cars are really expensive) – cylindrical cells have great cycle life. My feeling is that as the industry goes toward profitable BEVs that they will have to limit this reserve capacity, and the degradation will be passed on to the consumer.