Battery Life Related to Level 1 vs. Level 2 Charging?

[BILL GERTH]

Aside from the obvious convenience factor with Level 2 (240 volt) charging over Level 1 (120 volt) charging, is there any advantage for one over the other related to battery life? I know that thermal effects are very important in Lithium chemistry batteries, hence the sophisticated thermal management system in the Volt. Since the Level 2 charger can charge the battery in slightly less than half the time, this implies slightly over double the charging current with the Level 2 charger. This would also imply significantly increased heat within the battery due to the increased current flowing through the effective internal resistance. Does the battery TMS work during the charge cycle? Probably so. Are there any other positive or negative effects of using the Level 2 charger?

[MrEnergyCzar]

The positive is you'll use less KWH hours to fully charge the battery. The fast charge doesn't effect the battery life, I used to think that but was told otherwise by the top people here. Probably because the on-board charger is less than 4 KW.

Anyone here know why the battery life isn't affected?

MrEnergyCzar

[mike1]

Battery life is unaffected between L1 and L2 charging on the Volt because the L2 charging limit of the Volt (~3.3kW) distributed across all of the battery cells is still well under the threshold for decreased battery longevity of lithium-ion batteries. In hot weather, the TMS is undoubtedly essential for safely charging the battery at L2. In the Canadian winter for example, I strongly doubt that the battery would need any cooling even during an L2 charge...heck it might even need some heating!

[saghost]

Don't worry about it. Regen hits the battery with up to 50-60 kW at peak - driving in L hits with it 30 kW regularly.

I've read that it's common for Lithium Chemistries to be ok with 2-3C charge rates, and that some are ok with 5C. For the Volt, as a 16kWh battery, that's 32-48 kW, or 80 kW. Level 1 charging is up to 1.4 kW, level 2 is up to 3.3 kW.

You aren't even close to the range where heating/charge rate becomes a factor for durability (and yes, the TMS does operate during charging. I've occasionally poked my head in on the car and heard one of the radiator fans quietly whirring away.)

[BILL GERTH]

The positive is you'll use less KWH hours to fully charge the battery. The fast charge doesn't effect the battery life, I used to think that but was told otherwise by the top people here. Probably because the on-board charger is less than 4 KW.

Anyone here know why the battery life isn't affected?

MrEnergyCzar

Thanks for the quick response! That's good to know. Does anyone know how many KWH are required for a full charge in both Level 1 and Level 2 charging?

In my situation and driving patterns, I have relatively short trips and can operate EV all the time, even with my Level 1 charger. It takes just a bit of planning, but being retired, scheduling of trips is pretty flexible. There are some situations where faster charging would be convenient. If I can get the KWH charging requirements for Level 1 and Level 2, I can do a quick calculation of how long it would take for me to recover the cost to go to Level 2 charging.

I currently have a Kill-A-Watt meter to monitor my Level 1 charging. Is there a comparable metering system that will work on 240 volts?

Thanks in advance for any info. BILL

[solar_dave]

I currently have a Kill-A-Watt meter to monitor my Level 1 charging. Is there a comparable metering system that will work on 240 volts?

Thanks in advance for any info. BILL

There is always a TED. Not cheap as a kill a watt though.

[Jedi2155]

I would not go to Level 2 charging based on the cost alone, as despite being more efficient, you're still counting pennies here. I think its something like 12 kWh on L2 versus 14 kWh on L1 but don't quote me. The main benefit is the time it takes, but if you're on Time of Use pricing, thats a bigger savings (getting hit by the higher rates would easily eat into any efficiency savings).

[petefoss]

To me the utility of L2 charging is if it enables you to charge the battery fast enough that you can use it that same day. If all you are doing is charging faster that the difference in small. They key is converting that faster charge into EV vs CS miles.

[scottf200]

To me the utility of L2 charging is if it enables you to charge the battery fast enough that you can use it that same day. If all you are doing is charging faster that the difference in small. They key is converting that faster charge into EV vs CS miles.

Indeed the primary reason I got it was I come home after work charge up and go out later. This was primary one day a week but it turns out I use this regularly on weekend and other days. It turned out EVEN more important in the winter because my range is close to 30 so other days of the week I use it.

Also some have tight 'super off peak' windows so the short L2 charging is good for them.

[bonaire]

Another way to look at it is the savings of fewer kWh per day across a multi-year ownership could pay for the 220V charger installation quickly. The short trips idea makes the 220V idea a good decision. It depends on how many charges you need to do, if you intend to remote-start and pre-condition in the colder weather. If you live in Sunny San Diego, 120V may work out fine but if you live in Buffalo or other colder climates, 220V is a good choice. Since the OP is in MO, the colder winter months could benefit from pre-conditioning with 220V.