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The question is whether or not I should charge every time I get home. Here is the situation. This week I have been shuttling the kids to and from school total round trip of about 1.5 miles. So when I get home I just plug in to "top off". But I recall that for the cell phones or laptops that also use Lithium Ion Batteries the recommendation is that the battery is completely discharged before charging it up again. Should I follow the same recommendation for my 2013 Volt?
 

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Thank You PeteFoss but I have been told that on my other Lithium Ion devices there is a finite number of charge cycles before there is a degradation of total retained charge. I'd like to prolong my Volts battery pack for as long as possible. :)
 

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The Volt is a very smart car. When plugged in, it will not charge over about 80% capacity, thereby protecting the battery life. When you are driving on the battery, the battery will not discharge below about 20% capacity (the gas engine will come on), once again protecting the battery life. Other devices using lithium batteries are not smart like the Volt. Relax!
 

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Thank You PeteFoss but I have been told that on my other Lithium Ion devices there is a finite number of charge cycles before there is a degradation of total retained charge. I'd like to prolong my Volts battery pack for as long as possible. :)
So you're going to stop using regenerative braking when you drive?

The reality of Lithium chemistry is that the biggest thing that hurts it is DEEP charge and discharge cycles. That is why the Volt only uses 10kwH of its 16kWh pack. If after several years you use a cumulative total of 10,000 kWh, your pack will last longer if that was done via 2000 half charges than it would if you did 1000 full charges.
 

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GM recommends leaving the car plugged in whenever possible.
 

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My understanding is that yes, LI batteries have a finite number of charge cycles before they start holding a lower charge. But that makes it sound worse than it is. Here's what I've learned over the years from using LI batteries:
- The number of charge cycles is very high. VERY high. GM says that the batteries won't start to lose capacity for 8 years.
- Topping the battery up does not constitute a charge cycle. A charge cycle is a 100% discharge and recharge of the battery capacity - not how many times you plug it in. So, if you use 25% of the battery every day and recharge 25% every day, it will do a charge cycle every 4 days. Now, since the Volt doesn't let you discharge the battery all the way, the full charge cycle is actually longer.
- When you reach an excessive number of charge cycles, the battery does hold less of a charge -- but you might not even notice for a while. It doesn't just suddenly stop holding charge at XXX cycles, it holds slightly less over time. So, 7 years from now, you might be getting 5% less battery power. Frankly, this is less than the swing in capacity you see during winter, so I really wouldn't worry about it too much.

This is my layman's understanding of the way LI batteries work, so take it with that caveat!
 

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But I recall that for the cell phones or laptops that also use Lithium Ion Batteries the recommendation is that the battery is completely discharged before charging it up again. Should I follow the same recommendation for my 2013 Volt?
This actually stems from the older cell phones that used NiMH and NiCad batteries. These types of batteries function better if they are fully discharged from time to time. With modern Lion batteries, you want to avoid fully discharging them as much as possible. The more deeply they are discharged, the more damage will occur. I believe cellphones will stop functioning after a certain point, so the battery is never fully discharged.
Plugging the car in after a short drive will not have any negative effects.
 

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Your Volt uses 10KWH out of 16KWH capacity for actual driving. The battery is never fully charged or fully discharged.

This allows the car to rotate among the cells so that each cell has fewer charge/discharge cycles than the battery as a whole. The individual cells stay within their sweet spot for long life.

My Volt has been in use for over 16 months and 20,000 miles and any loss of capacity is not noticeable.

The way to get more effective EV range is not to sweat a mile of battery capacity but to fight and win the political battles to get free or reasonably priced charging stations where you work, where you shop, where you are entertained, and where you fly. It takes some savvy and patience, but Volt owners across the country are winning their fights.

When you want to renew your battery years from now, it will only cost $3000 retail.

Question: Has anyone on this board seen a significant drop in Volt EV capacity since purchase on a comparable time-of year-basis?
 

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When you want to renew your battery years from now, it will only cost $3000 retail.
Your points are all correct except for this one. The $3000 figure is what GM charges to dealers for short-term one-off replacements of faulty packs. Note that you can't just go to your dealer and pick up a spare at this price. If the day comes when customers start needing replacement packs en masse, this heavily subsidized figure will not apply.
 

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Your points are all correct except for this one. The $3000 figure is what GM charges to dealers for short-term one-off replacements of faulty packs. Note that you can't just go to your dealer and pick up a spare at this price. If the day comes when customers start needing replacement packs en masse, this heavily subsidized figure will not apply.
I don't follow you. A faulty battery would be a warranty repair not chargeable to the dealer. The most likely basis for a purchase this year would be road hazard damage, covered by insurance. This is rare but possible.

I believe that $3000 is forward pricing. GM believes that by the time the warranty expires, the cost of manufacture will really support that price.

However, if I ask my dealer to just go ahead and replace the battery right now at my expense, I don't think GM has another price in mind just for me.
 

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I don't follow you. A faulty battery would be a warranty repair not chargeable to the dealer. The most likely basis for a purchase this year would be road hazard damage, covered by insurance. This is rare but possible.

I believe that $3000 is forward pricing. GM believes that by the time the warranty expires, the cost of manufacture will really support that price.

However, if I ask my dealer to just go ahead and replace the battery right now at my expense, I don't think GM has another price in mind just for me.
Sorry, I should have clarified what I meant by "faulty", indeed I meant any one that needed replacing for whatever freak reason, including damage. GM knows that given a large enough sample size, there will be a few customers who will need an early pack replacement for whatever odd circumstances. And it knows that if they gave a five figure quote for a new battery pack, the owner would likely complain, the press would pick it up and be all over it, which would in turn scare off Joe Average who might have otherwise been on the fence about these cars, thinking they might be next for a five figure repair bill.

GM is taking a substantial per-unit loss on a very small number of replacements that will need to be done early in the Volt's lifecycle to avoid bad press that would cost them way more than a few discounted packs. At some point though, high-mileage Volts will start needing replacement packs en masse, and when the quantities reach that scale, GM will no longer be willing to eat the losses.

I also disagree that the price of the packs will fall to a natural $3000 within eight or ten years. If battery prices are to fall that far by 2019 (8 years after the first Volts were sold), I think you'd already see downward momentum of battery prices, which I haven't materially seen in the past year or two. Furthermore, if the pack price did fall to $3k, plug-ins/EVs will totally dominate small car sales, as that's about the price point where the payback is quick enough for the aforementioned Joe Average to accept over an equivalent gas powertrain. Not even the most rosy estimates have that happening any time that quickly.
 

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I also believe the $3000 cost only applies if you are exchanging your current battery for a new one. GM just announced their plans for the used battery power stations. My guess is that if a new battery really costs $7000 with full capacity, an old battery with 70% capacity might easily be worth $4000, thus allowing GM to sell a new battery for $3000 ($7000 new - $4000 trade-in = $3000).

These numbers are just an example.
 

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Can you cite one example where GM suddenly doubled the price of a replacement part years after the car was made? I can see complaints and even litigation unless GM puts an asterisk on the price list. Did someone buy a Volt based on an undisclosed low-ball replacement battery price? I just don't think GM will do it.

IMHO, this is not an academic discussion. If EVs are successful, charging stations will become standard parking lot amenities. 40 mile one-way range will be very acceptable even if bigger batteries are available. If you look at what wears out in a conventional car, such as exhaust system, transmission, disc brakes, engine, they just don't get a lot of use in a Volt. If I can refresh the battery for $3000, the Volt can be a permanent vehicle. It also becomes a very valuable used car.

Now the dealers, who make big money on trade-ins, and GM, which makes money on new cars, are left out in the cold.
 
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