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Discussion Starter · #1 ·
Chargepoint just installed a DC fast charger about a mile from my house.

There have been days where I have gone a 100+ mile adventure in the morning and wanted to head out again later in the day. Now, I've got a quick charging solution for those glorious days. 馃帀
 

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Discussion Starter · #3 ·
Great! If we had a good L2 charging option it might reduce the need for L3 if you had a few hours.
I have used DC chargers on longer trips, but the availability of one so close to home is handy thing.

I am fine with the lack of Level 2 charging. An onboard level 2 charger would add weight and dictate additional thermal management requirements. I understand the forward-looking compromise that HD made. Given the choice of Level 2 or DC, DC charging all the way.
 

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2022, Liquid Black
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L2 is a loss for some of us. L2 takes far too long to charge while out riding on an extended trip. And an overnight L1 charge works well for restoring for the next day.

I need L3 in order to be able to go on longer than 100 mile rides. In my situation, with a dedicated 20A outlet in my shed, overnight L1 charging is convenient. I would never use L2.

I keep seeing more L3 chargers pop up, month by month, along my riding routes.
 

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The problem with L3 is if you use it too much, then you have to deal with accelerated battery degradation. That is why they have this section in the LW manual. If you break it down, at most 20% L3 charging and I don't think they mean back to back to back L3 charging. So this really limits how useful L3 can be as with almost all EVs using lithium ion.

When recharging the RESS, choose Level 1 (110V to 220V) charging when possible. Level 1 charging causes the least amount of stress to the RESS.

鈥 The RESS does not limit the number of times a Level 3
DC fast charger (480V) can be used. However, morefrequent DC fast charging will stress the RESS more than Level 1 charging. If possible, avoid using DC fast charge, exclusively. The suggested best practice is to alternate your charging between Level 1 and Level 3 DC Fast Charge in a 4:1 ratio (4 Level 1 charges to every 1 Level 3 fast charge).

鈥 The battery will protect itself from thermal damage, however
extended periods of time operating at high temperature can speed the chemical aging process and shorten RESS
lifespan.

The RESS is designed to charge quickly to 80% of its capacity,
at which point the charge rate then slows to reduce the rate of RESS degradation. If the battery is too hot or too cold, the charge rate will automatically reduce to a sustainable level.

Charging below 0C/32F or over 50C/122F degrees will result
in significantly increased charge time. Under extreme usage or extreme temperature conditions, the RESS may limit its performance in order to prevent damage.
 

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Discussion Starter · #6 ·
You can do back to back DC charging on road trips etc.
Your overall ratio of L1 to DC should be 4:1, but you shouldn't give yourself fits on the order of your charging. A few DC charges back to back every once in a while isn't going to hurt a thing.

With cars, using DC charging almost exclusively has practically no impact on battery life. That's because cars have active thermal management around their batteries -- very different from our relatively simple RESS aircooled setup. Many EV cars pre-condition/warm-up their batteries for best charging performance. My Taycan fires up the heat when my destination is a charger.

HD is very conservative with the charging curve on these bikes. I fully expect to get their engineering target of a decade of service or more before replacement.
 

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You can do back to back DC charging on road trips etc.
Your overall ratio of L1 to DC should be 4:1, but you shouldn't give yourself fits on the order of your charging. A few DC charges back to back every once in a while isn't going to hurt a thing.

With cars, using DC charging almost exclusively has practically no impact on battery life. That's because cars have active thermal management around their batteries -- very different from our relatively simple RESS aircooled setup. Many EV cars pre-condition/warm-up their batteries for best charging performance. My Taycan fires up the heat when my destination is a charger.

HD is very conservative with the charging curve on these bikes. I fully expect to get their engineering target of a decade of service or more before replacement.
The Taycan, and Teslas, preheat the packs to optimize the charging rate. They assume you are in a hurry. There is always a trade-off. The trade-off is batteries don't like high temps.

I hope HD is conservative with the charging curve but I'd encourage people to do some reading at www.batteryuniversity.com

Here is a relevant quote from BU. BU-502: Discharging at High and Low Temperatures

All batteries achieve optimum service life if used at 20掳C (68掳F) or slightly below. If, for example, a battery operates at 30掳C (86掳F) instead of a more moderate lower room temperature, the cycle life is reduced by 20 percent. At 40掳C (104掳F), the loss jumps to a whopping 40 percent, and if charged and discharged at 45掳C (113掳F), the cycle life is only half of what can be expected if used at 20掳C (68掳F). (See also BU-808: How to Prolong Lithium-based Batteries)

I was a practicing engineer for many years. My days were filled with compromises. I am sure they dealt with the same thing during the development.
 

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I'm not hyper focused on battery degradation.

There is a theoretical accelerated RESS degradation - but how much really occurs in the Livewire over time is really not known.

One of the best studies on EV battery degradation was done by Idaho National Laboratories. It compared four identical vehicles. Two were exclusively charged at Level 1. Two were exclusively DC fast charged. The battery capacity was tested new, and every 10,000 miles to 50,000. At 50k miles, the vehicles that were exclusively DC fast charged still had ~72% capacity compared to new. As opposed to ~75% for the Level 1 only vehicles. That's not worth worrying about. And how a Livewire will really degrade is still a bit of an unknown, especially with the battery artificially having reserve capacity held back

Personally, I'll be happy to fast charge a couple times a week, and enjoy 200-400 mile days, rather than waiting for additional hours for Level 2 and be stuck waiting for the bike to charge.
 
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