Battery Management Systems

This topic isn’t actually a Hybrid Vehicle topic but it’s worth spending a little time on it.  If you pay attention to some of the latest trends under the hood of conventional engines you’ll no doubt come across the concept of battery management systems.  So what is it all about?  Well, I’m glad you asked.

Your conventional electrical system on cars doesn’t have any way to determine the state of health of your battery.  You know this if you’ve ever been stranded somewhere wondering why your starter makes that dreadful “Click” when you turn the key.  Yes, you have indicators on your instrument cluster that will tell you your charging system is not operating correctly but there’s really nothing there that tells you your battery is on it’s last legs.  Battery Management systems are typically consist of the following.

• A current sensor on your negative battery cable
• A communication between this module and your engine computer
• The ability to shut down (or reduce) electrical loads throughout the vehicle
• The ability to shut off the alternator on command

So how does it all work?  Well, the state of health of the battery is determined by the module on the negative post.  It does this by knowing key parameters of the battery that are provided by the battery manufacturer and measuring the current, voltage, and temperature of the battery.  This information is fed back to your engines computer which already has access to other key pieces of information like engine RPM and an idea of what electrical loads are running at the time.  With this information all in one place the computer can make some decisions regarding how it should operate.

For example, during a starting event, the main computer can shut off the alternator and other loads making the high current draw event of the starter a little easier on the starter.  The computer could also determine that your battery is in such a state that we can begin a long charge cycle.  This might happen if the temperature is favorable for the battery accepting a charge and it seems that the RPM’s are pretty stable (like on the highway).

Another example is that long term parking at the airport.  You may not realize that your car’s electrical system goes to sleep after about 30 minutes but certain events can wake it up again (like other peoples key FOBs!).  What this means to you is that larger than expected currents are flowing from your battery causing it to drain faster than the engineers would like.  You could end up returning from your trip to a dead battery.  The Battery Management system can deal with this by sensing the battery state and shutting everything down.  This proactive measure keeps the battery from getting into a deep discharge state which even if you are not stranded, can shorten the life of your battery considerably.

Another benefit of Battery Management systems is that they can improve your fuel economy.  It does this by managing when your alternator is turned on.  Under certain drive cycles (depending on the state of health of your battery) you can just run on battery power alone.  Your alternator can be turned off which significantly reduces the load on the engine.  It can be turned off because the battery is being monitored to make sure it doesn’t discharge too much.

Well, that’s it for now.  If you haven’t heard about these systems yet, I’m sure you will be soon.  It seems that any technology that reduces those MPG’s is going to be advertised or otherwise made known so that you know the automakers are doing everything they can to get green.

Deminski and Doyle show

Hey, I just found out they have a blog!  I stumbled upon it by accident.  Strangely enough, they aren’t yet the number one return on a Google search for “Deminski and Doyle”.   They are, however, the number one result for “Deminski and Doyle Update”.

If you drive 3 hours a day to and from work you know you miss these guys.  Just a note, I wish they would switch over to a different blogging platform.  I prefer Wordpress (like this site) over Blogger.

At any rate, here’s the link to the boys…

http://deminskianddoyleshow.com/

Deminski and Doyle Update

OK, I got my answer.  Wikipedia has an entry that describes the situation.  You can find it Here.

It’s a real sad episode in the story of Detroit radio.  There’s nothing left.  Jay Towers and Bill Mcallister (sp?) do the best they can but they’re not D & D.  The drive home is a real drag listening to those sports guys.  What are they going to talk about when football season is over?  Turns out that Deminski and Doyle have a no compete clause which means we won’t be listening to them for a least a year.  If they pick up another gig that offers broadcasts on the internet, I’m there.

Good luck guys!  I wish you would have set up your own website or something so we can get regular updates.

Deminski and Doyle

Well, my first drive to work in the new year was a drag.  It turns out that Deminski and Doyle, my favorite radio personalities, are no longer on in the mornings.  I was hoping that they would reappear in their old time slot in the afternoons but it didn’t happen.  I searched in the news for some blurb on what happened but haven’t found out anything.  If someone knows, please post.

97.1FM used to be my favorite radio station but it has steadily gone down hill.  Of course it all started with Howard Stern moving over to sattelite.  I can’t blame the station for that but all the other moves have just been silly.  They’re latest scheme is to be an all sports station.  Good luck with that.  I can only take about 5 minutes a day of that.  Hopefully they’ve found a nice pool of listeners with dollars to spend on their advertisers.  This listener (and his wallet) is moving on.

Verizon DSL with a Linksys Wireless Router

I had a little trouble over the weekend with my home network.  I’ll post the solution here since I wasn’t able to find anything that could help me online.

It all started with my sons friend who wanted to access my wireless LAN so he could plan Age of Empires with my son.  Its been a year since I’ve needed the password to let someone onto my network and I couldn’t remember or find it anywhere.  Thinking this would be easy, I just resetted my Linksys WRT54G back to it’s factory settings, and generated a new password.  Well, all was find on the home network in that I could see the desktop PC and the three laptops.  The boys were even able to play their game.  The problem was that I couldn’t get to the internet anymore.  I was pretty sure I must have forgot a setting in the Linksys so I kept playing with it for hours trying to get it right.  I accessed my neighbors unsecured wireless to get on the internet for some direction but all I found was information that conflicted with each other.  Some people said to set it to DHCP while other said that only PPOE would work.

It appeared that I wasn’t getting an IP address (a valid one) from the Westell DSL modem.  I disconnected the Linksys from the Westell 2100 DSL modem and plugged my laptop directly into the Westell hoping to at least get online without having to use my neighbors network.  I couldn’t get online this way either.

Next day I called Verizon and they were able to get me back online after about 40 mins of rebooting the modem and doing some DNS flushing and told me they would patch me into the Linksys help line for the home network portion.  Basically, once they got me online being patched into the Westell directly, they were done with me.  They patched me into Linksys which immediately put me on hold.  I hung up and here’s what I did to fix it.

After listening to the Verizon guy walk me through this I concluded that when I reset my Linksys back to factory settings, I was still attached to the powered up Westell.  I must have knocked some settings in the Westell when I did that.  Apparently the Westell was trying to adjust for the new settings in the Linksys and it was then thrown off track.  Wish I could be more technically specific here but I really don’t know that much about this stuff.  Well, what I did next was make sure the Linksys was disconnected from the Westell and reset it again.  I logged into the Linksys using the address 192.168.1.1 and changed it to PPOE with the correct username and password that the Verizon guy provided me, and saved the setting.  I then set up the wireless network password.  I didn’t mess with anything else.  I then plugged it in to the Westell and it worked like a charm.

I guess the moral of the story is that if your going to reset anything in your system and you know you’re going to have to go in and make adjustments to the system, do it when it’s disconnected.  I should have known better.