Real-world L.A. driving/HOV speeds/parking on hot asphalt:

[studio460]

[Daily commute: 60 miles round-trip (South Bay to Burbank, CA).]
[Home: Level 2 (planned); work: standard, 120V outlets only.]
[Road type: 100% freeway with a single large incline/decline (Sepulveda pass/Cahuenga pass)].
[Freeways used: Work-bound: 105E/405N/101S/134E; home-bound: 134E/5S/110S/105W/405S)].
[HOV: Available on 90% of freeway commute (Including FasTrak lanes).]

By the way, do you charge while at work on your 60-mile commute? Or is a 60-mile round-trip commute totally doable from your home-charge?

Your round trip commute between South Bay and Burbank should be easily done on one charge at home, if you have a Level 2 EVSE. Using the Level 1 that comes with the car could do the trick as long as you are able to plug in maybe 14 hours before you leave in the morning.

I commute ~80 miles RT, Santa Clarita to El Segundo. Can't make it on one charge using the carpool lane (70+mph) due to the 1200ft elevation difference between the two points and having to get over the Sepulveda pass... would need about 2kWh more energy to do so. Your shorter distance and smaller difference in elevation gain/loss (about 400 ft) makes your situation much more doable on one charge.

60-mile, round-trip freeway commute:

Thanks a lot, v_traveller, for that detailed, and specific reply! It's really great to hear from another person who knows the Los Angeles-area freeway system. I didn't realize the Sepulveda pass was 400' in elevation (I'll be taking my Garmin Oregon 600 GPS device on my way to work tomorrow).

HOV speeds:

In addition to my HOV sticker, I'll be getting a FasTrak transponder when I get my FFE, which brings up another issue. I would be fine driving at optimal electric speeds on the freeway, but as I'm sure you know, if I drove 55MPH in the 405 HOV lane, I would end up pissing off the entire city (that said, often the 405's HOV lane is slower than the regular lanes). From your reply, I take it that you drive 70MPH+ when using an HOV lane just for that reason. I sometimes take a different route home, since the Westside will still be congested, while the 110S/105W is less heavy toward the latter part of rush hour. At least there are two HOV lanes on the 110. But, since I mainly take the 405, I'm not sure my 60-mile RT commute could be completed on a single-charge at those speeds. What do you think?

Keeping batteries in-check on hot San Fernando Valley parking lots:

I also read your blog (which is excellent, by the way), and found out about the hot-asphalt issue. At home, I live near the beach, and would be parking my FFE on a white, concrete driveway. But at work, I park on a hot, black-asphalt lot. My schedule varies every day, so I could arrive at anytime between 7AM and 4PM, depending on what I'm assigned, so I'm more likely to park on an already-heated space than not. I'll typically be able to park near any one of two 120V-adjacent parking spots (but not necessarily guaranteed 100% of the time), so it looks like I may be able to keep my Lithium temps in check during those hot days of summer in the valley. This seems critical, since I know from using Lithium batteries for video applications, they're very sensitive to temperature. Thanks for all your advice!

 

[v_traveller]

I didn't realize the Sepulveda pass was 400' in elevation (I'll be taking my Garmin Oregon 600 GPS device on my way to work tomorrow).

Oops, sorry to mislead you... I meant to say that the difference in elevation between South Bay (I picked Torrance, 89ft) and Burbank is about 400ft. The Sepulveda Pass per Google is 1134ft. Which shouldn't be a problem for you; when I take the pass southbound my Wh/mi goes up significantly on the climb (from ~200 Wh/mi at the 101 to ~260 Wh/mi at the top of the pass, with no traffic), but by the time I come down on the other side and pass the 10 freeway I'm down to about 190 Wh/mi or less.

I would be fine driving at optimal electric speeds on the freeway, but as I'm sure you know, if I drove 55MPH in the 405 HOV lane, I would end up pissing off the entire city (that said, often the 405's HOV lane is slower than the regular lanes). From your reply, I take it that you drive 70MPH+ when using an HOV lane just for that reason. I sometimes take a different route home, since the Westside will still be congested, while the 110S/105W is less heavy toward the latter part of rush hour. At least there are two HOV lanes on the 110. But, since I mainly take the 405, I'm not sure my 60-mile RT commute could be completed on a single-charge at those speeds. What do you think?

LOL! I think you are absolutely right about the 405 HOV lane being schizophrenic - peer pressure seems to dictate 70+ mph on open sections, but there always seems to be congestion, often at a standstill, somewhere between the 10 and 101 interchanges when commuting North to South in the morning, and South-to-North in the evening. I always thought that traffic flowed better on your side of the freeway, but perhaps I'm a pessimist, always thinking that the grass is greener on the other side of the concrete center divider.

I think you'll be fine on one charge via the 405, even if it involves 70+mph jaunts in the HOV lane to mitigate any risk of getting shot. As you probably know, folks around here seem to slow down for the uphill climbs even when all lanes are wide open, which I think helps our situation. My round-trip averages 235-260 wH/mi, depending on traffic and whether or not I run the A/C. Typical is about 246 wH/mi, and that's going with the flow in the HOV lanes. If you get the same efficiency, you'll use up 15kWh of charge going to work and back, leaving you a comfortable margin. I'm thinking that you'd have to run close to 300 Wh/mi to get to the point where the FFE will warn you that you're low on charge just as your exiting the 405.

Losing consciousness, will have to pick this up tomorrow... Thanks for the kind words, studio460!

 

[studio460]

Thanks again for your detailed reply!

 

[v_traveller]

... okay, I'm back.

So about the heat...

Forum member michael, who has an OBD scan tool, posted this a month after I wrote the blog entry:

http://www.myfocuselectric.com/forum/viewtopic.php?f=15&t=2035#p11468

Based on his findings, the above message is not an indication that the battery is in immediate peril; it's a warning that it's hot outside, I guess to suggest that bad things can happen if we don't plug in. In michael's case, the message came on and his battery was still in the low-80F range.

After reading his post, I'm thinking that even though I parked on hot asphalt my battery was probably nowhere near being too hot just yet, because I didn't get an email message that the battery is in trouble. The message I got last year when it actually did get too hot looked like this:

"Hello Vin,

Sparky theCommutator has a hot battery, which will limit the vehicle performance. Please plug Sparky theCommutator in to bring the battery temperatures to optimum operating range."

So long story short, I'm not sure how long it takes to eventually heat the battery up to an alarming temperature in 101F heat when parked on a pre-heated parking space, but it's something more than one hour.

 

[michael]

It seems to take a really long time. The battery seems to be well insulated and to have large thermal mass.

If possible, keep the car in the shade, and if possible leave the windows open a bit. Or get a reflective car cover.

However, once you start charging the temperature goes up faster.

By the same token, when it's cool the battery cools down very slowly. It's not uncommon for the battery to be in the 80's early in the morning and without having been charged even though it's in the 60's outside.

 

[studio460]

Thanks, Michael!