Charging at 1/2, better or worse for battery life?

[mdh]

As long as you stay away from keeping the pack at or near 100% SOC for long periods of time, the SOC doesn't have a have a huge effect (diminishing returns). Like others have said shallow cycles are better.

What are your thoughts on the charging limit "slider?" I have an 85 model and usually do 50-60 miles per day. I usually set the slider to about 185 mile limit. Am I really helping my pack by not going to 93 percent level (about 232 miles). I am running .61 sw.

 

[DennisLevitt]

I live in Los Angeles, so I have the municipally-owned Dept of Water and Power. I have a dedicated TOU EV meter and I'm charged .057 per Kw. Yes, under 6 cents per. People nearby, but outside LA, are served by privately owned SoCal Edison, and they pay way way more.

 

[jerry33]

What are your thoughts on the charging limit "slider?" I have an 85 model and usually do 50-60 miles per day. I usually set the slider to about 185 mile limit. Am I really helping my pack by not going to 93 percent level (about 232 miles). I am running .61 sw.

There are diminishing returns as you lower the percentage. That is there is a big gain between 100% and 90%, less between 90% and 85%, and still less between 85% and 80%. FWIW, I charge to about 210 miles (my daily driving is similar to yours: 50-60 miles). That gives me enough for two commutes plus some unexpected. There is no point in having so little charge that you run out of range.

 

[djp]

What are your thoughts on the charging limit "slider?" I have an 85 model and usually do 50-60 miles per day. I usually set the slider to about 185 mile limit. Am I really helping my pack by not going to 93 percent level (about 232 miles). I am running .61 sw.

We have a couple of threads on SOC that are worth reading:

What should my ideal charge percentage be? (FWv4.5))
Is a standard charge significantly worse than an 80% charge?

Best rule of thumb is to charge to a high enough level to cover your expected use plus a safety reserve. The batteries are happiest when stored at a lower SOC, especially in warm weather. Here's a table that shows the number of years it takes for Li-Ion NCA batteries to lose 20% capacity when stored at various states of charge and temperatures.

SOC	20C (68F)	30C (86F)
100%	7 years	4 years
90%	11 years	6 years
80%	14 years	8 years
60%	23 years	12 years
40%	36 years	19 years
20%	49 years	27 years

 

[montgom626]

Wonder if this applies to a main battery that is managed with regards to it temperature? Is a MS battery allowed to get to 86 degrees without any intervention?

 

[djp]

Wonder if this applies to a main battery that is managed with regards to it temperature? Is a MS battery allowed to get to 86 degrees without any intervention?

Yes, 86 is within the BMS range. Cooling doesn't kick in until above 105.