Time is the coin of your life. It is the only coin you have, and only you can determine how it will be spent. Be careful lest you let other people spend it for you. -- Carl Sandburg
There's only one rule that I know of, babies -- goddammit, you've got to be kind. -- Kurt Vonnegut

May 18, 2014

LiFePO4 Batteries - First Camping Use at SprinterFest

SprinterFest Boondocking

I spent the first weekend in May boondocking at the SprinterFest on my new LiFePO4s. My batteries easily lasted the 3 days running my marine fridge and the usual few minutes of furnace in the morning, water pump, etc. The fridge ran almost constantly but I'm not sure why - it may still have issues of its own. I love having double the amp hours (AH) I had with the AGMs. I had used about 

I drove up Thursday night as I had arranged to have my serpentine belt replaced at 8am in the morning at the Sun Motor Cars shop who were also hosting the SprinterFest. It was 8 years old and I've been told that a broken one does a whole lot of expensive damage to Sprinters beyond stranding me on the road. 

One of the downsides to owning a Sprinter is that widespread competent mechanics are not available. The Sun shop has a very good reputation and a very nice Sprinter-specific facility. While I might have been able to replace the belt myself, I didn't want to risk not getting it back on right and the access is tight.  While there, I had them do an oil job too.  They very nicely let me have the dog in the waiting area where she got behave and stay calm training and lots of free pets. They have free wi-fi also which was nice.

When I got my van back, they had done a decent wash on it too, gratis. It looked great. Later at the SprinterFest, the mechanics said the one who did my work was surprised by finding the cats inside. I told the front guy there would be 2 cats in there so the mechanic wouldn't be surprised but he didn't relay the message. They told me the mechanic took a selfie with my cats. Cute.

Before I took the van to the shop, I let the dog have some exercise in a deep grassy area by the back lot. She went behind a bush and disappeared. I called and called to no avail. Getting worried, I hopped into the van and went up the road about a quarter mile where I saw some men at a big truck type facility in the parking lot. I pulled in and asked if they had seen a big yellow dog and there she was. They had grabbed her since she came running up to them to greet them and appeared on her own. Whew, but really! She hadn't gone off like that at the previous 2 Sprinterfests. One guy said he tried calling the numbers on her tag but it wasn't in service. Yikes! I forgot to change her tags when I changed cell phone numbers. He said she would have stayed with him all day if necessary. As soon as I got the van back from the shop, I drove up to the nearest PetSmart and made new tags with the new numbers along with a new tag for the cat.

After we were done, I settled into the back lot of Sun where they have us camp out for Sprinterfest. I had some volunteer work to do with my computer anyway so I completed that. No one else showed up until after 6:30pm.  A few vans arrived and one of them wasn't staying for the SprinterFest but was filled with dog crates and dogs. They have a business of transporting dogs. They built a bed way up high in the van over the crates because they wanted to maximize the number of dogs they could transport at once. A few of us went to dinner together. We have a very nice camaraderie developed over the 3 years I've come to the SprinterFests.

For the day of the SprinterFest, Saturday, I counted 38 Sprinters and there were a few people in other cars as well.

One guy that has come for the 3 that I have has an interesting saga. He's a youngish (30s) guy with tech skills. The first year, he showed up with an old T1N dual wheel cargo van with little improvement to it and was rough camping inside the tin tent. He had been having mechanical problems but had dreams of living in the van to cut costs and renting his house for income. He planned a do it himself buildout. The 2nd year, he showed up in a Sprinter box van that he planned on building out and living in. It had the advantage of square walls and quite a bit more space than the van interior and ran reliably.  This year, he was back in the old dually van with a new engine in it. He had done a lot more work on it with insulation, a killer stereo system and the electrics needed for it, a marine fridge, and a couple of cabinets.  He found the box truck was too big to navigate narrow city streets and thus wasn't going to cut it for his needs so he went back to his original plan in the cargo van. He plans on mainly city living and his personal cleanliness needs will be met with gyms. Toilet and cooking facilities will be in the van along with only interior water tanks/piping so he can use it in winter. He has rented out most of his house but wants to get out of it completely so he can charge more for rent. It is a viable plan for simple, inexpensive living as long as the cold winters here will work for him. It is a lesson in how a too big vehicle can make it harder, not easier. He's got an idea for making the bed self-leveling that will be interesting to see when done.

A few of us stayed over Saturday night for the circle-the-vans after pizza party. It was marred by showers but still fun. In the morning, we had breakfast together before heading back home Sunday afternoon. I was letting my dog run around in her favorite meet and greet mode. I got distracted for a few minutes Sunday morning and she disappeared again. When I got my phone again, there was a message that they had my dog about a mile away (glad I got the new tags!) because she had run across the road behind Sun to greet a man and he grabbed her to protect her from the road traffic. Before, she had stopped at the road considering it a forbidden barrier. Damn dog is now an adult (4 years old) but clearly, I am going to have to put her on the rope because the old no no's are not keeping her in safe bounds. Thankfully, I got her back but the training I've been doing to stop her from initiating greeting humans is not fully working and now former barriers don't work.

The LiFePO4s:

Some things are quite different with the LiFePO4s. With my 15 amp circuit at my house, it takes 2 cycles to fully charge them as my new charger shuts off after 16 hours and it needs longer than that to charge from a deficit of some 150AH out of my 200AH capacity. I haven't had it on a 30 amp circuit yet. To start charging, I have to disconnect the shore power, then connect again for the charger to start again. No float. 

The 3 days boondocking used about 160 AH but half of that was with the fridge on the manual setting which was using 5 amps. When I set it to the normal/auto, it dropped to 3 amps. The fridge froze the freezer plate on battery power because it sees the higher voltage and thinks it is on shore power.  Getting the more efficient computer version might not have been the best idea with the LiFePO4s because of this. The regular thermostat governed variety probably would have been better.

I had a trickle charger that shunted a few amps to the engine battery to top it off when I was on shore power but the higher voltage from the LiFePO4s made it think it was on shore power and sipped power from the batteries. So that is disconnected now.

My engine alternator charged them nicely while driving but just like on shore power, the BMS shut off the charging when they were full. No floating. Short driving periods resulted in some charging each time but it wasn't long enuf to fill the batteries.

My trimetric battery monitor shows the AH used after being off charging but while charging, it reverses and shows far fewer AH without me resetting it. That is, I use 150AH but when the batteries are full after a charge, it shows 4AH an hour or so after it is done. I guess it is measuring the deficit from full. I never saw that with the AGMs.

When the batteries are full, the charger gets shut off and won't start again no matter how long or how much juice is used unless it gets disconnected from shore power and then reconnected so I have to pay more attention to the charge levels when plugged in. The no float aspect means I can't just let it sit plugged in for long periods with no attention.

It will be interesting to see how these do with solar but I'm not there yet.

1 comment:

  1. Good job on keeping us updated on your batteries, glad your happy. I know I got a stroke at what you paid, but I almost made deal with EPS to get $400 AH , when by accident I stumbled across a different supplier. Don't wanna let the cat out of the bag yet but I got lets say a MEGA battery deal, will store 16kw - a little heavy at 400 lbs, but it's all good for OverTheTopCargoTrailer. I just wish I could use one of those EV charging stations and load 6kw per hour :-) . Once I figure how to install I will keep you updated. But you were 100% correct in the smaller versions a 100AH comes to about $1,000 with BMS , actually in marine use they sometimes pay 2 x3 times that amount for the exact same system as yours.

    Cheers OverTheTopCargoTrailer


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