LiFePO4 Batteries: Discussion Thread

[vwhammer]

The body of the battery should be negative.

I'm not trying to hurt your feelings but, based on what I see in some of those pics, it seems that maybe not enough care was taken in securing, installing or handling of the batteries.
Perhaps the damage was done during the removal process but there are a lot of nicks and tears in the plastic film on your batteries beyond where your primary damage is.

If the battery body were to contact a dissimilar metal then galvanic corrosion could occur eating away at the body until all your juice oozed out making matters even worse.

There is usually some form of electrolyte in LiFePO4 batteries.
This can range from a liquid to more gel like.
Some liquid types are absorbed into a porous material.

Either way, whatever happened sure did make a mess and wreck those batteries.

I think this helps to illustrate why the LiFePO4 chemistry is considered safer than other lithium chemistries.
You might not have been so lucky, if you want to call it that, with something else.

[owokie]

[Howesight]

Hey Alika:

Sorry to see what happened to your LiFePo4 cells! I knew nothing about these cells before twigging to how great they are at the current price point and started reading a lot on them. Looking back at your earlier posts about your installation, and with the knowledge I have now, a few things jumped out at me:

1. Did you use a BMS? I did not see one mentioned in your post.

2. The plastic coating on the LiFePo4 cells is not adequate to protect the cell casing from electrical contact - - it's barely enough protection to allow for transport from China. As we now know, a lot of work needs to be done to insulate the cell casings electrically.

3. Your Cyrix Li-Ct 230A DC-DC unit might have allowed over-voltage from your alternator, thus damaging the cells;

4. In my Syncro Vanagon, I get accumulation of water in the box under the driver's seat when the van sits in steady rain. She is a garage queen now, but when camping in the rain, I get water in this area. I think it is from my door seals. Water on or near the aluminum casings on these LiFePo4 cells will degrade and corrode the casing, accelerated by the presence of electricity.

5. The aluminum casing on the prismatic LiFePo4 cells is very thin. It can't really take any impacts for any length of time.


Here's what I did to protect my 280Ah cells which, due to their size, but using the same thin aluminum casing as the smaller cells, are even more vulnerable to physical damage than your 150Ah cells:

I put thin plastic cutting boards bewteen each of the cells which you can barely see in the pic above.
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'86 Syncro Westy SVX

[xoo00oox]

Regardless of if this is what caused Alikas problems or not, This has brought up a very important thing. Don’t let theses cells sit on or near anything metal, they need to be insulated. The entire case is positive! That blue film is too thin to rely to be insulation.

[ALIKA T3]

Hello!

I'll try answering every question:

They were not in service, just the negative end connected to chassis, the Cyrix Li-CT not connected to anything yet on the charging source end. Just sitting there waiting for me to get to them.

I didn't know care was needed to install these, I was one of the first ones to buy them last year, dropped them in, forgot about them and had to deal with other things first to get my Syncro road worthy. So no water intrusion either. The van is like new with 17K original miles.

I put bamboo spacers between the cells but the bottom and sides were not protected.
So the explanation is clear as crystal now, the insulation got damaged 🙄

The whole assembly was well clamped, but I guess vibrations killed the plastic film fast, which I didn't know was essential. There also was a threaded coupler between cell #1 and 2 and outside cell #4 which was rubbing at the base sides.

That's some sketchy cells to play with, and the battery box under the seat doesn't allow much insulation room.

FML
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Silicone Steering Boots and 930 Cv boots for sale in the classifieds.
Syncro transmission upgrade parts in the Classifieds.
Subaru EJ22+UN1 5 speed transmission
http://www.thesamba.com/vw/forum/viewtopic.php?t=416343
Syncro http://www.thesamba.com/vw/forum/viewtopic.php?t=4...num+gadget

[ALIKA T3]

Oh, and I do read voltage between the positive lug and the body. Body is negative. That's crazy.
_________________
Silicone Steering Boots and 930 Cv boots for sale in the classifieds.
Syncro transmission upgrade parts in the Classifieds.
Subaru EJ22+UN1 5 speed transmission
http://www.thesamba.com/vw/forum/viewtopic.php?t=416343
Syncro http://www.thesamba.com/vw/forum/viewtopic.php?t=4...num+gadget

[vwhammer]

Well crap. That really is a bummer but at least you likely sorted out the primary cause.

Unfortunately you became the guinea pig for all of us in this instance.

Live and learn, I guess, even if it did cost you a fist full of Benjies.

Also unfortunate is the fact that all the cells will likely need replaced.
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Pretty normal daily driver build
https://www.thesamba.com/vw/forum/viewtopic.php?t=708418&highlight=

4x4 build
https://www.expeditionportal.com/forum/threads/volkswagen-vanagon-4x4-conversion.162055/

[ALIKA T3]

Yeah, it blows. I had already bought a sketchy battery before that and decided it was a bomb...that's why I went with these cells which were my primary option a long time ago, but none matched the dimensions I was looking for at the time.

I posted ( read bitched) on my stories on IG and had one Vanagon member telling me they stopped to use them. I got a few sketchy looking pictures of exploded cells that caught on fire.

I might go back to them later, for now I'm against the wall and batteries don't ship to Hi.... I bought a GW battery for now to get me going, will install it in CA once I get there.
What a PITA!!
_________________
Silicone Steering Boots and 930 Cv boots for sale in the classifieds.
Syncro transmission upgrade parts in the Classifieds.
Subaru EJ22+UN1 5 speed transmission
http://www.thesamba.com/vw/forum/viewtopic.php?t=416343
Syncro http://www.thesamba.com/vw/forum/viewtopic.php?t=4...num+gadget

[dobryan]

[shagginwagon83]

[Crooked Designer]

Wondering about others who have taken full auxiliary battery systems and converted to LifePo4 systems.

I don't want to muddy up this thread, so wondering if that is worthy of a new thread to focus on what you have already running and need to swap out/add to get to a safe and well functioning LiFePO4 aux system. I've read (and learned) a ton on this thread, but there still seem to be lots of questions about what is and isn't necessary anymore when converting setups. I guess that thread would be more around the other devices vs. the actual cells.

Or should I just keep that conversation here?
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'85 Westy full camper, Subaru 2.5L, 5 speed SubiGears + 5speedbus shifter kit

[xoo00oox]

I just received my cells this past Saturday from AliExpress. I had ordered 16 100ah cells on March 2, so it took 2 full months. I never got a tracking number, they just showed up and when I look back at my AliExpess account it still shows them as awaiting delivery.
It seems that there is a big demand for these Lifepo4 cells now and they are out of stock in many places and the price seems to be creeping upward.

[Howesight]

[owokie]

[Howesight]

Thanks for clarifying, Owokie. I was (for once) trying to be concise in the post above and got #7 wrong.
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'86 Syncro Westy SVX

[ProspectiveOwnergon]

So this company says they balance the cells and everything, so do I really need to get the 30v 10a DC Power supply to balance these or can the BMS cover it?

[Howesight]

Most of us (myself included) are not buying the highest/best grade of LiFePo4 cells. Even with the best cells, an annual balancing would be normal maintanance.

Layered on top of that is the fact that the balancing by our friends in China may not have been, ahem, perfect.

I think buying or gaining access to a proper power supply is cheap insurance. My cells already illustrate differing charging rates, so I am going to have to do this (top balancing) in the near future.
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'86 Syncro Westy SVX

[ProspectiveOwnergon]

Thanks Howesight!

I was debating buying the 135ah batteries labelled "New" for $231 shipping from China (august arrival), or say screw it and drop $440 for Grade A 120ah...The pictures of the 135 even show a little swell so that caused me concern...

You suggesting I switch to the "New" for $231 and balancing myself? (emailed james for BMS )

[Howesight]

The best approach to cheaper cells from China, I think, is to get the balanced set, but approach that as only a starting point. You still need to top balance when you receive them. My vendor was local to me, imported a large quantity from China, waited for delivery, then checked all and top-balanced all before final sale to guys like me. I picked up the day after he completed top-balancing the cells.

It is preferable to have all your cells come from the same manufacturing run. This is most likely to create identical resistance and amp/hour capacity in each cell. Unfortunately, any seller you ask is tempted to say "yes, these are all from the same run", even though this may not be so.

The trick on AliExpress and similar platforms, apparently, is to find a reliable rep with good communication. Months ago, I found on a solar/LiFePo4 forum, that some folks in US and Canada had good experiences with a woman in China who is active on the DIY Solar Power Forum.

Basically, if a person seeks to import a large quantity of cells from China, AliExpress sellers have decent communication and treat buyers reasonably well. For purchasers seeking small quantities, many sellers treat them poorly.

The woman I dealt with appears to have carved out a niche. She realized that potential small-quantity purchasers on the DIY Solar Power Forum were trying to identify LiFePo4 sellers that were reliable and had good communication. She became one of those deemed trustworthy and now has volume and excellent reviews/feedback, which bring lots of new and repeat business. One poster on the DIY Solar Forum recommended using very simple language with the main points as in the following example:

I am writing to you from Vancouver, Canada.

1. I would like to buy 4 pieces of your new, Grade A 280Ah cells plus bus bars.
2. What is your price for 4 pieces?
3. What is your charge for shipping to Vancouver, Canada, Postal Code V6J 0A0 ?
4. What is the expected delivery date?

Thank you!

So:

1. Join the DIY Solar PowerForum;
2. Then search for Amy Wan (Luyuan). She is with Shenzhen Luyuan Technology Co., Ltd,
3. Here is a link for her: szluyuan.en.alibaba.com which hopefully still works.
4. Tell us here on the Samba how well your transaction goes!

I ended up going with a local cell vendor who could supply my cells right then and there with no shipping delay, so I never did complete a transaction with Amy, but her communication when I enquired was excellent and the delivery costs and details provided were also excellent.

By the way, the guy I purchased my 280A/h cells from now assembles them into batteries with a BMS, packages them in a steel box, and sells the finished product for $2,000 CAD! I told him there was a niche market here for VW Westfalia and RV folks. It appears he already knew that. We shall see how his new gig works out:

https://royerbatteries.com/
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'86 Syncro Westy SVX

[ProspectiveOwnergon]

Thanks for the wealth of intel! I've actually messaged Amy many times and she doesn't have the 120ah batteries in stock for the couple times I've asked her. But she has been STELLAR to communicate with...just wish she had the product

Will ask her again. I am not sure how to see if we have a local source here in SoCal, so will have to trust on Aliexpress