MORE BATTERY ISSUES: The 12 volt House bank

After installing and testing of the new 8A4D battery for the electric propulsion bank I noticed the 12 volt house bank was experiencing some issues too. What tipped me off was the Morningstar Solar controller was cutting off voltage to it's output lugs. I had wired my Engel refrigerators, AIS, and Fan to this output. The controller cuts the output when the battery voltage drops below 11.4 volts. It looks like one or both of the 8G27 Gel Cell batteries BIANKA uses for the house 12 volts had reached the end of their useful life.   As I opened the compartment that held the batteries I could feel some heat rising from the space.

I took out my infrared temperature probe and took some measurements. One of the batteries measured 141 degrees fahrenheit.

 Way too warm for comfort. The temperature of the second battery had a much better reading of 107 degrees fahrenheit. Much cooler but, still warmer than normal.

Since both of these house batteries are operated in parallel it said to me that the hotter battery was the major problem. As the cooler battery was trying to continually charge the defective warmer battery. I turned the battery switch from "BOTH" to the individual settings and took some voltage readings. The warm battery was around 10.5 volts and the other was over 12 volts. So one battery was truly defective but, I replaced both since ten years providing the house 12 volts was a good run and best practice is to have both batteries the same age when installing them.

After I installed the new 8G27 batteries I used the Centech Battery analyzer  to get a baseline reading of each.

They appear to be pretty closely matched though their cold cranking amps was slightly lower than the  spec but, I am not too concerned. I will recheck them after they have been in operation for a bit. All in all I can not complain about these MK 8G27 Gel batteries.  They were installed when I converted BIANKA to Electric Propulsion in 2008. So ten years was a god run. I hope the new ones last as long.

BATTERY INSTALL 2016

The sailing season has been delayed while I deat with the damaged battery SNAFU. Two new 8A4D batteries arrived to replace the two that were damaged in the original shipment. The only difference is that the batteries probably have different manufacturing dates. When I ordered the original batteries the battery company said it could provide batteries manufactured the same day. But, now that probably is not the case. Whether or not it will make that much of a difference only time will tell.
So I loaded up all five hundred and twenty pounds of batteries into the car and took them to the boatyard.

I had BIANKA launched because it would be easier to load the batteries into BIANKA while floating at the dock.
I did make some major changes in the placement of the new batteries. I reversed the location of the the terminals of batteries one to three. I just turned them around so all terminals are located along the port side. Battery four was off by it's self next to the other batteries facing aft on the starboard side. The was because the engine stringer which held up the original battery platform did not extend far enough aft to allow for the fourth battery so I installed it next to the other three. Unfortunately this also meant I had to empty out two cockpit lockers to do any maintenance on the pack instead of one. It was a real pain.
By building a metal extension battery holder out of slotted angle iron and extending it off of the existing platform:

I was able to line up all the battery terminals on the same side and make them easy to reach after only emptying one of the cockpit lockers. This will make for much easier access and maintenance in the future.

 Other than doing the install on the hottest day of the year the install went pretty good. There might be some tweaks I might want to do but, they could wait until the off season. The next step is to get the batteries wired up. I did have some concern that since I changed the layout of the batteries that one or both of the main battery cables would not reach the proper terminals. We'll see how that works out once I start wiring thing up.

BATTERY ANOMALY PART TWO: Readings and observations

 I looked to the cause of why Battery 4 of my 48 volt Electric Propulsion bank was not charging properly. Since the terminals for this battery can best be accessed by the starboard  locker hatch I first had to empty out the locker and then squeeze my large frame down into it.

Taking off the protective caps on the negative terminal I had quite a bit of corrosion on it.

 This was because I had become somewhat  complacent in checking and cleaning the terminals. Mostly because up to now the battery charging had been operating normally.  The failure of battery four just happened a few days ago. After cleaning the terminals I used an battery tester to check it:

The readings above show a voltage of 10.87 volts and an internal battery resistance reading of 196.2 milli ohms. Which is a much higher resistance reading than when I last checked it on February 12, 2012.Which was 2.43 milli ohms. So obviously something had changed in this battery.  I will try a few more attempts at charging but, I don't think things will approve much. TO BE CONTINUED.

THOUGHTS OF AN ELECTRIC SAILOR: The Battery investigation one year later

I was thinking of the disturbing battery issue I had on board last year. When all of a sudden one of my batteries refused to complete a full charge using my   Dual Pro Quad 4 battery charger. It took a few times  of repeated charging but, finally the battery came back to being comparable to the other batteries in the 48 volt propulsion string and has stayed there ever since.

Some thoughts on what happened:

1) The main cause seemed to be that I was hanging a 25 milli amp load on this particular battery to run the Paktrakr Battery Monitor. I had done this years before with no problem but,

2) I had also removed the 48 volt Marine Air X Wind Turbine over the winter to replace it's blades and have it repainted. So the only charging that was happening was from the 48 volt solar panels and an occasional charge from  the Dual Pro when I check up on the boat. During the winter solar availability was limited to short daytime charging. So that 25 ma drain started to add up. Possibly sulfating the battery enough to prevent it from ever really getting a full charge over the winter months because of the constant 25 ma load.

Over this past winter I no longer had the Paktrakr hooked up to that battery and I had the 48 volt Marine Air  X wind turbine also helping with the charging. The battery that was causing the trouble last year now charges with the rest of the batteries. The lesson learned is that to avoid taking any load off a single battery in a series string. Also when a battery suddenly refuses to charge all is not lost and one may not need to run out and get a replacement battery.