Justification for 300 mile battery

[Dan5]

I've been thinking about this and here's some justification for getting the 300 mile battery

1. Resale value:
If you sell it after 1 degradation cycle, (70% of max left), it's about equal to the 230 mile battery pack +/- 20 miles. Based on the Panasonic charts for the rumored battery, that's around 150,000 miles

If you sell it after 2 degradation cycles (49% of max left), that's about equal to the 160 battery pack +/- 11 miles.

If you can get a "used" car with 150,000 miles or just sell the battery at that time, you make out on that deal. The battery is the major wear part, spend 10 K repairing the car and you have a "new" 230 mile version.

2. Increased performance- access to the sports version

3. Delaying or avoidance in replacement costs
If you drive 50 miles per day, the 160 cuts it close after 2 degradation cycles (300,000 miles), 230 after 3 cycles (450,000 miles), 300 mile after 4 degradation cycles
For myself it's really
160- less than 1 degradation cycle (7 years)
230- less than 2 degradation cycles (10 years extrapolated)
300- between 2-3 cycles (16 years extrapolated)
I could delay getting a replacement battery to the point when I do get it it will cost 26% of the initial cost. 230 about 43%, 160 about 55%

Assume the batteries cost $142/ mile
300 costs- $42857
230= 32660
160=22720

replacements battery costs, assuming 8% drop in battery costs per year
300= $11288
230= $14018
160= $ 12496

 

[Mycroft]

For me, #2 is the major reason for the 300 mile pack. Otherwise, even at 70%, the 230 mile pack would be more than adequate for me. And $10,000 is a lot of money just for some hypothetical future resale value.

When #2 was announced by Elon, I immediately upgraded to the 300 mile Signature.

 

[user497]

replacements battery costs, assuming 8% drop in battery costs per year
300= $11288
230= $14018
160= $ 12496

Looks like your 300 mile amount is wrong. Personally I think all 2-car families should have 1 EV and 1 Gas car. Drive the EV for the commute and most fun weekend trips and drive the gas car for long distance trips. That's what we are doing and I don't see myself needing more than a 160 mile battery (based on how many miles I put on my roadster). Sure in 10+ years when batteries are much cheaper and lighter I may feel differently but I think my strategy makes the most sense for the immediate future.

 

[AnOutsider]

Wasn't there something about a bigger pack being more resilient to charge cycles as well? Before sport was announced I decided I wanted 300m. It just made sense for me if I wanted a "no compromise" sedan.

 

[dsm363]

Sport option would be reason for me as well. When you start looking at keeping a car more than 10 years though, you have to really think if you'd keep a car that long. Some people do but many people would have already replaced the car with a new one by year 7-10.

 

[ckessel]

Here's my thinking in favor of the 300, copied from an earlier post in a different thread. The context was whether it was worth buying a 160mile up front and upgrading later.

Battery cost will decrease, just not fast enough to overcome the cost of throwing away your initial battery and replacing it with a new one. Some of the calculations on battery cost have put it pretty high (can't remember the article now, but it's something like "back of napkin battery calculation cost"). I'm going to invent some numbers for the sake of illustration.

Today:
160 price = $10000 (granted, rolled into initial car purchase, but you are paying for it).
300 price = $30000 (Remember here I'm talking "go buy a new battery", not the $20k option upgrade price)

Let's say you upgrade from 160->300 3 years later and battery costs have dropped 25%:
160 price = $7500
300 price = $22500

So, if you bought the 300 mile straight off, you'd pay an extra $20k more than if you bough the 160.

If you buy the 160 right off, then upgrade to the 300 later you're paying $22.5k to upgrade. The key question then becomes, how much can you sell the old 160 battery for? Remember, it's old technology now and it's had degradation. Can you get enough that it was really worth waiting 3 years to upgrade to the 300?

The more expensive the base battery (say costs were 20/30/40k instead of the 10/20/30k I used), the better it is to upgrade right away rather than wait. If the battery cost curve drops more rapidly over time, say 20% a year rather than 8%, then it swings back the other way.

So, all that was my thinking. From what I can tell with the knowledge available today, it's better to just go big on battery right from the start.

 

[Mycroft]

Wasn't there something about a bigger pack being more resilient to charge cycles as well?

Yes, the more infrequently you have to charge in "range" mode, the better.

 

[rlawson4]

Can someone explain the charge cycle issue to me? My main question is: Would it be better to top off the battery every day or charge less frequently? If I have the 300 mile battery and travel 30 miles one day, should I top off or wait to charge? Some days I travel less than 30 miles round trip. Other days I can travel 150-200 miles. Thanks.

 

[Mycroft]

I'm 99% sure that Tesla's user manual will state to plug in the car every night in standard mode, (which will be about 80% of the full capacity of the battery), regardless of how many miles you drove that day. The car's computer will calculate the proper charging for the pack.

You would only charge it in range mode when you're expecting to make a longer than normal trek. For example, my brother-in-law is about 125 miles from my house. So I would charge the 300 mile pack in range mode just to be on the safe side. Once I have his place set up to allow me to charge at 220v, I probably won't use range mode any more.

 

[NigelM]

Consider ease of resale as a justification. The higher battery range that I start with, the easier it will be to sell the car at a future date. A potential future buyer can always "trade-up" to my car if he's considering a specific range he needs, but "trading-down" below his desired range is never an option. Ceteris paribus, a higher range will always have a larger market and therefore easier resale.

 

[Robert.Boston]

I'm reluctantly coming to realize I need the 300-mile pack. I drive 170 miles from Boston to my place in Maine approximately one round-trip per week from May through September. Mid-trip charging is not an option, and my wife will have our ICE vehicle with her up in Maine (but she also needs to be able to get to and from Boston).

So: a 300-mile battery, degraded to 71% of original, operating in normal charge mode, has 170.4 ideal miles. Close, but much of the drive is along slower roads.
OTOH: a 230-mile battery, degraded to 71% of original, operating in range mode, has 163.3 ideal miles.

Ah, well, no getting around basic math.

 

[Trnsl8r]

I'm shooting for 300 as well, mostly for the no-compromise on the family car. If I picked 230 and then had to compromise on a road-trip because of it, I'd kick myself more than in the opposite scenario (I think).

Sports option has nothing to do with it though. I can wait an extra second to get to 60.

 

[Mycroft]

Life is short Trnsl8r, those seconds start to add up! :biggrin:

 

[GSP]

........ Personally I think all 2-car families should have 1 EV and 1 Gas car. Drive the EV for the commute and most fun weekend trips and drive the gas car for long distance trips.

Better to have 1 EV and 1 EREV. At least until there is a SuperCharger on every corner.

As for justification: "Too much is really just barely enough." Get the 320 mile option. You'll have the baddest EV on the planet.

 

[Dan5]

A charge cycle is from 0% to 100%. This is called deep cycling. From the battery spec sheets from Panasonic, it looks like it retains between 60-70% after around 500 deep cycle charges. This is very abusive to the battery though- more like a worse case scenario. To put in perspective, it's like running to empty then over filling in an ICE car (you damage the fuel pump and system if you do that on a continuous basis). To prolong the battery life, it's recommended to use a 220 or 120 and slowly charge it and keep the car within the 10% to 90% range (mid 80% capacity of the battery). That really prolongs the life of batteries
In terms of battery chemistry, it's ok to use the 480V fast charge occasionally, but it's not recommended to do it on a regular basis (faster charging means more heat generation in the cells when charging) and there is a slight risk of "cooking" (degrading) for some cells. (the lithium colbalt oxide family batteries have this issue).
If you are going 150-200 miles you should have no problem, with the 30 miles, I would charge it once a week or something.

 

[richkae]

I plan to use the 320 mile Model S as our workhorse car for all driving including all long trips.
I don't plan on driving more than 500 miles in any one day because my family doesnt want to spend more than 8 hours in the car.
I've driven 700 miles solo in 12 hours, with only gas stops, but my family will not do that.
One or two 30-60 minute charge stops is fine with me just as long as there are amenities nearby, the children need stops anyway.
Whatever hotel we stop at will need to have a 7+ kW charger to get the car full by the next morning.

 

[goyogi]

300 mile version for me, but the reason is freedom. I rarely drive more than 200 miles. I want the peace of mind of loooong range. Stomp on it without worry, forget about charging every once in a while without regret. I've forgotten twice in my Volt to charge. No regrets as my commute is short and I've set the OnStar app on my phone to remind me at 10PM if it's not plugged in.

 

[Mycroft]

Same here richkae. We're keeping the SLK55, but whoever has the farthest to drive is going to be driving the Model S and the other gets the SLK. It's a win-win! Although, I'm keeping the Tesla for the first month to myself. :-D

 

[AnOutsider]

300 mile version for me, but the reason is freedom. I rarely drive more than 200 miles. I want the peace of mind of loooong range. Stomp on it without worry, forget about charging every once in a while without regret. I've forgotten twice in my Volt to charge. No regrets as my commute is short and I've set the OnStar app on my phone to remind me at 10PM if it's not plugged in.

100% agreed

 

[gg_got_a_tesla]

To play the devil's advocate here, here are my (probably misguided or misinformed) reasons to settle for the 230 or maybe, even the 160 (given my daily commute of < 60 and longest weekend road trips of ~100):

1) 300 has newer chemistry (does it?) so, could, in theory, have more issues in the first year or two?!
2) Why make the car heavier than I need it to be? Wouldn't I effectively be "burning" more electricity per mile traveled in a heavier car?
3) The car price savings upfront could be invested elsewhere in a prudent/safe manner towards a new Tesla a few years later (or atleast towards a replacement battery pack) - if not towards my son's college fund :smile:
4) Larger carbon footprint in manufacturing and subsequently recycling (or disposing of) the larger number of cells in the 300 pack
5) Show EV naysayers - by living with the smaller battery pack for a long period of time without any issues - that range (that's not really required in a given situation such as mine) is not really everything
6) Be minimalistic - why consume more than I need?