Tuesday, October 20, 2009

Topsail Middle School 6th Grade visit

We had the opportunity today to show the MR2 to sixth grade science students at Topsail Middle today. The students were very interested in the car and the SMARTT Challenge program. Some of them will be participating in the Jr. Solar Sprint this year. Thanks to Adam, Arik, Brady and Jeff for talking to the middle school students about the EV class.

Sunday, October 18, 2009

Fall Festival

We displayed at the Hampstead United Methodist Church annual Fall Festival on Saturday morning. It was a cold fall morning and to make matters worse, the Coastal Cruisers car club did not show up, so we did not get the traffic and attention were would have gotten if they had. It actually looked like we had broken down at the Church! Visitors to the festival kept parking all around us so we decided to leave around noon. Sometimes it is better to cut your losses. Anyway,
thanks to Ryan, Brady, Ashley and Aaron for working a shift even though they didn't have many viewers. There will be many more opportunities in the future to spread the word of Electrics.

Friday, October 2, 2009

Doughnuts and Specific Gravity

2 dozen glazed doughnuts from Surf City Deli
Dakota looking through the refractometer

The true measure of a battery state of charge is the specific gravity value. As you can see on this page, a fully charged battery should be 1.265. We made a chart and measured the specific gravity of the electrolyte of each cell in all 13 batteries. We used an instrument called a refractometer to do the testing. We are trying to determine if we have any batteries or cells that read lower than the others. Readings should not vary more than .05 differences between cells. So far, so good. We have a couple of batteries that are "suspect" right now and we may have to desulfate them and recheck later. We did find last week that we had one battery with a dead cell, so we replaced it and things are looking better for now.

P.S. I bribed the students with doughnuts to get them to work!!