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Sodo Samba Member
Joined: July 06, 2007 Posts: 9603 Location: Western WA
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Posted: Sun Dec 05, 2021 12:19 pm Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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One year later and all is well (I think).
I kinda don't 'believe' the % charge levels presented by the BMS though.
I think it's guestimating wildly.
We took an 8 day trip, using only 100w solar in November and returned home with 49% remaining.
Then 2 days later with the fridge OFF it reported 15%.
Well anyway the batteries haven't 'swelled'.
I planned to take it all out last year after the first camping run and "tidy up".....
but I have done nothing.
Posting this so you fellers can hold me to it,
to actually 'tidy up'.
I want more protection, knowing the metal battery case (under that thin blue plastic) is "positive".
Wondering about a battery heating pad under the batteries, appx 14x14" for 4 batteries laid flat.
Not sure I'll ever need it, but would be nice to have (in that rare condition).
Ther is a 12v unit on Amazon. I don't know what other draw I have that could self heat the batteries (other than the heating pad draw). _________________
'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb |
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ledogboy Samba Member
Joined: September 19, 2005 Posts: 578 Location: Scappoose, OR / Oakland, CA
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Posted: Sun Dec 05, 2021 1:05 pm Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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FWIW, my van has the type of lid that screws down (not the hinge). I replaced it with a piece of plexiglass that I had cut to size at Lowe’s. Used the original as a template for the screw holes, and no more worries about shorting! _________________ 1986 Westy Weekender
Now a full camper
1.8t Syncro conversion
Some people call him Maurice... |
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ProspectiveOwnergon Samba Member
Joined: May 22, 2020 Posts: 211 Location: SoCal
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Posted: Mon Dec 06, 2021 2:53 pm Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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Sodo wrote: |
I kinda don't 'believe' the % charge levels presented by the BMS though.
I think it's guestimating wildly.
We took an 8 day trip, using only 100w solar in November and returned home with 49% remaining.
Then 2 days later with the fridge OFF it reported 15%.
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Yeah, the BMS don't have a true shunt or coulomb counter, so does it based solely on voltage and your usage via Bluetooth. So barring something alsways connected and storing that intel, the BMS will fire up with full capacity after your device hasn't connected for awhile. I've debated a shunt, but realistically everything works well |
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kguarnotta Samba Member
Joined: April 01, 2004 Posts: 1160 Location: Woodstock, NH
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Posted: Mon Dec 06, 2021 3:19 pm Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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I like the idea of a battery heating pad - but space is so tight on mine - I don't know how to get it in there.
I bought a couple - and a sensor to turn it on and off - but have not got around to installing it. _________________ -Kevin
Lincoln, MA
'86 Triple Knob Syncro w/EJ22
'78 Westy
'69 Single Cab
'65 Kombi - EZ-Camper |
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DeLvxe Samba Member
Joined: January 08, 2019 Posts: 106 Location: Seattle
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Posted: Mon Dec 06, 2021 3:32 pm Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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Sodo wrote: |
I kinda don't 'believe' the % charge levels presented by the BMS though.
I think it's guestimating wildly.
We took an 8 day trip, using only 100w solar in November and returned home with 49% remaining.
Then 2 days later with the fridge OFF it reported 15%.
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Agreed. I have the same BMS as you and don't really believe it. I don't fault the BMS as this is not their function.
I have this coming to me from China. It is a shunt with bluetooth. Some good reports on the DIYsolarforums and really affordable.
https://diysolarforum.com/threads/bluetooth-battery-monitor-0-120v-0-600a.28564/ _________________ 1991 manual camper with EJ25 |
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Sodo Samba Member
Joined: July 06, 2007 Posts: 9603 Location: Western WA
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Posted: Sat Mar 05, 2022 2:52 pm Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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installed July 2020.
March 2022 ( 20 months ) report.
I took my cells out to inspect.
Intending to re-install them a little better than before.
But found some problems.
One cell is leaking.
Two have "something" in the "cell window".
One cell window has nothing to report.
They all have appx 3.18v and the system seems to be working but I don't have an easy way to do a capacity test.
Maybe just put about 20 amps of lightbulbs on it and time it with a stopwatch.
150AH can run 20 amps for 7.5 hours.
I wonder if it's OK to replace just that one leaking cell. _________________
'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb |
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shagginwagon83 Samba Member
Joined: February 07, 2016 Posts: 3794 Location: VA/TN
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Posted: Sat Mar 05, 2022 9:45 pm Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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Sorry to hear this. I know it was a lot of work to get these batteries to fit.
It all depends on if you can get a replacement of similar kind. I don't know if you can find 150aH batteries anymore. And to get a single cell - it might be expensive.
I mean it looks like you might have two bad cells. Again it depends on the price of replacements, but it might be best to upgrade to a 300aH setup. I have been rocking my 150aH setup similar time to you. However I installed mine in the area where your DC charger is. They have pressure from a top bar holding them together. The setup is working great since Fall of 2020 I believe.
These cells are not meant to be in vehicles are all really. Ideally many smaller cylinder cells like Battleborns have are ideal for mobile and especially Marine applications. We can get away with having these bigger cells (like 272/300ah setups) in our Vanagons because of clamping (or pressure) - to really isolate the vibrations - especially between the links of the cells.
_________________ Brandon
"Jo Ann" - '83.5 Westfalia EJ22e w/Peloquin
Instagram @joannthevan |
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pretzilla Samba Member
Joined: May 11, 2015 Posts: 4 Location: East Bay, CA
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Posted: Mon Mar 28, 2022 10:27 pm Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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Sodo wrote: |
installed July 2020.
March 2022 ( 20 months ) report.
But found some problems.
One cell is leaking.
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Compression cases are a thing now. plywood ends, angle aluminum, threaded rods. Cells need to operate under compression - even when initially top balancing!
Also, cells on their sides like that is bad, mkay? they prefer to be upright, or on edge - not great, but it should work. But flat on their face like under seat is no bueno due to the interior construction and distribution of electrolyte.
This writeup seems to have things going great!
https://www.thesamba.com/vw/forum/viewtopic.php?t=740626
Good luck, and thanks for sharing your adventure! |
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DuncanS Samba Member
Joined: October 17, 2013 Posts: 4583 Location: New Hampshire
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Posted: Mon Mar 28, 2022 11:12 pm Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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Sodo wrote: |
Kinda wondering why I shouldn't just cut the whole tab off.
EDIT- I've been under the driver's seat so many times now with this battery project.....kittens be damned, I just cut the driver-side tab off completely. |
Absolutely. Cutting the tabs off on both seats is one of the first things I do when I get a new T3. Well, after taking out the middle seat that is.
I also drill out the rivet in the seat pivot bracket that holds the spring loaded catch. If the tab is gone what is that for? In fact what is it for anyway?
But Sodo, I'm worried about your install. 150 AH is an unbelievable amount of power. Looking at all kinds of different tables, a crude estimate is there is the equivalent of about 4 sticks of dynamite under your seat with those batteries. If something goes wrong, it is going to get really ugly very quickly. Very likely too quickly to stop the car, unbuckle your seat belt and get out. Putting those batteries directly on the steel makes me extremely nervous. Lipos don't like shocks. You already have at least one compromised battery and they haven't been right over the front wheels on a bumpy dirt road yet, or even a paved road with pot holes. At the very least, I'd want them on 3/4" of foam rubber. And then how do you constrain batteries just lying on foam rubber? You'd want a box around them. I don't see enough room under the seat for that. And what about cold weather charging and discharging. It's tough to get heat under the seat and the steel is outside and.............. don't know how cold it gets in Western Washington, but on camping trips?? For safety, thermal stability and access, under the rear seat seems like a far better choice. Fuses? Where would they go and how would you access them? And if you need a battery warmer, there is no room for that under the drier's seat either.
Nervous Nellie Duncan |
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Sodo Samba Member
Joined: July 06, 2007 Posts: 9603 Location: Western WA
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Posted: Mon Mar 28, 2022 11:40 pm Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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Duncan the batteries are surrounded by foam, with hold-downs.
The foam is 1/4", just thick enough to isolate them from the steel and aluminum.
I haven't addressed vehicle vibrations at all, but there's no battery movement.
I don't think a 5,000 lb vehicle vibrates much but that's a guess.
It's my understanding that LiFePO4 batteries do not have a fire danger.
These are not LiPo batteries (lithium-ion polymer).
Some other folks are having failures with cells standing on end.
For all I know they could be just 'grade B'' LiFePO4s failing.
Some percentage of them may have failed anyway.
I have an 80A fuse on the other end (by the start battery) but none on the LiFePO4.
I need to fuse each battery!
pretzilla wrote: |
Also, cells on their sides like that is bad, mkay? they prefer to be upright, or on edge - not great, but it should work. But flat on their face like under seat is no bueno due to the interior construction and distribution of electrolyte. |
Back in '20 pretty much all of the sellers stated the cells could be mounted in any orientation.
I wonder why they would state that?
Perhaps everyone Copy & Pasting misinformation from the other sellers?
Were these batteries such new technology the sellers were unaware that they needed to be vertical?
Can anyone point me to definitive info stating this (orientation)?
12psi of compression appears to increase the number of cycles in the battery's lifetime.
They won't remain flat when they charge, they will bulge a little each time they charge.
So the centers of the square faces will press together harder, which will be more than 12 psi, perhaps much, much higher pressure if constrained with solid steel rods (no spring).
I worry that this compression info isn't much more validated than the "any orientation" claims that were common way back in '2020.
Compression purports to extend lifetime from 2,500 to 4,000 cycles.
I have cycled the cells ~50 times in 1.5 years.
So with NO compression the batteries may last 2500 cycles
(at my current rate 2500 cycles is 75 years)
With compression the batteries may last 4000 cycles
( 4000 cycles is appx 120 years)
Adding compression to the install seems unlikely to pay off (at my usage).
Anyway I haven't yet re-mounted the cells, but have to do it soon.
2022 van season is coming up FAST (like almost 'tomorrow')
I don't think I'm going to heat the batteries.
But I'd be interested in knowing the "real deal" to make best decisions. _________________
'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb |
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DuncanS Samba Member
Joined: October 17, 2013 Posts: 4583 Location: New Hampshire
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Posted: Tue Mar 29, 2022 12:25 am Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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Sodo, thanks for your lengthy and considered reply. I feel much better knowing the batteries are surrounded by foam. They sit right over 16 gallons of gas which is pretty safe. And across the way is the lead acid item which is safe. And we have propane for the Westy stove with is also safe. Safe as untoward events are rare. When T3s go up it's usually because a relentless fuel pump sprays gas over a hot engine with high tension electricity and unfused 12 volts all over the place with insulation which can melt and then Bob's your uncle.
Safe is what you deem it to be. Is driving a 30 year old car sitting right up front while on top of 16 gallons of gas safe? Well, we all do it. As it is said about VW bus drivers, we are the first on the scene of an accident.
Here's where I got the 4 sticks of dynamite from. https://www.topspeed.com/cars/warp-coils-seem-clos...85365.html
"Gasoline energy density is 47.5 MJ/kg and 34.6 MJ/liter; the gasoline in a fully fueled car has the same energy content as a thousand sticks of dynamite.
A thousand sticks of dynamite. If we release that amount of energy while driving 5 or 6 hours, it's easy to see the problem of trying to quickly recharge an ecar. We can put those thousand sticks in the gas tank quickly as it is a different form of energy from what actually is used to propel the car. The electricity you need to charge an ecar is the same form you use when driving. So trying to put the the same energy form we use in 5 or 6 hours in a few minutes, just 'ain't gonna happen..........yet.
https://www.grepow.com/blog/can-lifepo4-batteries-explode/
Have fun and enjoy your car.
Duncan |
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Sodo Samba Member
Joined: July 06, 2007 Posts: 9603 Location: Western WA
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Posted: Tue May 03, 2022 8:41 pm Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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Its our 11th night out since replacing the leaky cell and I haven’t seen chargel levels less than 91%.
No alternator charging, charging only with the 100w panel in the cargo area.
Fridge is maintaining 34-36F.
Pretty easy to camp in May, in California (SyncroFest!!), with 100 watts & 150Ah.
OK……so what about this 91% number?
Is it believable?
Right now its 9pm, dark and it says 97%.
I’ll bet its still above 90% in the Morning. _________________
'90 Westy EJ25, 2Peloquins, 3knobs, pressure-oiled GT mainshaft, filtered, cooled gearbox
'87 Tintop w 47k 53k, '12 SmallCar EJ25, cooled filtered gearbox
....KTMs, GasGas, SPOT mtb |
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DuncanS Samba Member
Joined: October 17, 2013 Posts: 4583 Location: New Hampshire
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Posted: Wed May 04, 2022 4:35 am Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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Congrats, you seem to have it all dialed in.
Duncan |
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jacklar Samba Member
Joined: April 08, 2018 Posts: 9 Location: Ontario, Canada
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Posted: Wed May 04, 2022 8:21 am Post subject: Re: 150Ah LiFePo4 flat under driver seat + swivelectomy |
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Sodo wrote: |
Its our 11th night out since replacing the leaky cell and I haven’t seen chargel levels less than 91%.
No alternator charging, charging only with the 100w panel in the cargo area.
Fridge is maintaining 34-36F.
Pretty easy to camp in May, in California (SyncroFest!!), with 100 watts & 150Ah.
OK……so what about this 91% number?
Is it believable?
Right now its 9pm, dark and it says 97%.
I’ll bet its still above 90% in the Morning. |
I have almost the exact setup but have the cells upright in the battery compartment under the drivers and have the charger and fuses under the seat.
I'll be getting the van out of storage soon. I'll let you know if I'm noticing the same thing. I don't entirely trust the BMS either. I've thought about setting up a shunt to better track usage but so far the 150ah is more than enough for all our needs and I don't think we've ever come close to using more than 50% of the capacity without it recharging up. But I'm kinda curious to know how the shunt vs. the BMS will compare. |
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