I Think My Project Lithium Battery Failed After 3-days.

Well like anything else that gets manufactured I guess there can be a bad such and such and so and so under the hood or under the cover as the case may be. So there's that others seem to be having very good luck with the battery so I would hope it's a fluke and you'll get it worked out and that'll be that. So then with regular battery tech from the Prius to nickel metal hydride everything was good with your Prius on the route and everything else or maybe that battery was old and tired got it I have an '09 with the brand new Toyota battery everything seems to drive great 47.1 etc. I run it as a service vehicle I don't think I try to break next when I pull away from what would be a whipping post or a mailbox or someones shed etc . But we drive the heck out of the car.my battery's never been over you h bottom of case hot maybe 110 or. So. Is that too hot when it's 100° out?

 

The hybrid mechanic guy from Miami who posts YouTube videos on the PL battery and it’s components mentioned, in his detailed disassembly video, that the reason he did the disassembly was because he had to replace one or more cells anyway that failed early on. So it does happen it seems.

 

Harbor Freight has 1/4” torque wrench on sale this weekend.
20 to 200 inch pounds.
$12 with coupon code 31458366 online or in store

 

any chance you can send a listing link? i will go buy one today

 

1/4 in. Drive Click Type Torque Wrench

Wait I found it, and the coupon code works. Buying right now! Thank you

 

Yes, a P3000 error code... Would love to know which subcode if you access to Toyota Techstream?

But there's no issue with the pack... I've been testing a prototype version of exact design in a Gen2 and Gen3 Prius for 2 years now. The problem you have is most likely corrosion inside the hybrid battery ecu that's causing bad readings/microshorts in block 14:



Taking apart and cleaning or replacing the ECU will fix this. Also replacing the voltage sensor harness (Wire Frame No.2) with a new one helps because that's how the corrosion gets into the ECU via seepage at old NiMH pack's negative terminals. This is a known problem with older Prius in humid areas and nexcell has only had 3 packs out of 200+ sold with this problem. So now you're number 4. But with just a couple hours work you'll have this problem fixed.

To address this problem in the long run the voltage balancing electronics in the Nexcell module(s) are being updated in version 2.0 to prevent these bad readings even when corrosion is present.

 

The picture shows surface corrosion. Unclear to me how cleaning that off is going to make a bit of difference in the electrical properties of that part of the conductor. If you mean that the corrosion goes right through the plastic and the conductor on the other side is also corroded, so that the connection to the pin (or whatever) on the other side is compromised, then yes, cleaning it will reduce the resistance through that connection. Unfortunately, perhaps only temporarily. If the outer plating metal (gold in the best case) has been displaced by the corrosion then the underlying base metal (nickel, copper, some alloy?) is not protected and may corrode again pretty quickly. I once had to repair an instrument at work because of this issue. Cleaning the contacts didn't stay fixed, it eventually required removing the entire socket on the circuit board and replacing it, even though only a couple of pins were affected.

 

Hi @TheLastMojojomo ,

Thanks for sharing the info, as we discussed in the email, we will help you find the root cause as well as provide warranty if battery is indeed the source of the issue.

Best,
Jack

 

yes, I always advised to replace the battery ECU if corrosion were found, problem with corrosion is that it short the battery blades and slowly drain them, a new ECU is about $220 new from dealership and $100 used from eBay.
@PriusCamper is the first person that I know of ever attempted of the repair/clean up, seems to be holding up so far.

 

That's my buddy Jose from Trinidad and Tobago, he got my consent to post the video on YouTube since the Ver. 2 will be out shortly
and yes, battery issue is inevitable, playing with chemistry is hard but a more robust QA process can definitely help.

 

At first it just creates noise/bad sensor readings from micro shorts but as it grows it will eventually short out the plug on the other side. It's very common type of hybrid battery failure in areas with high humidity like Florida and Pacific Northwest... I've got a whole box of hybrid battery ECUs that were all fried in the exact same way and we're hoping to one day track down a supply of female plugs so we can repair the circuit board because the only damage is the plug.

 

Just be wary of those cheap torque wrenches, I had one that failed to click and ended up with a broken valve cover gasket bolt...

 

Can you provide a link for this? I'd buy 10 right now.

maybe you meant to say "a new ECU is about $720 new from dealership"?

 

Often the manufacturer's name is stamped somewhere in the plastic, but a big magnifying glass may be needed to read it. It might be on the bottom part, blocked by the circuit board. If so, unsolder the connector and have a look. It might also be in the narrow area above the pins in the contact region.

The other approach is to measure the pin number, spacing, and geometry, then start on a site like Digikey or Newark and use the filters to narrow the field until you find either the original connector or something compatible with it.

Worst case scenario - it is a custom part made by Denso (or whoever) only for Toyota. All hope may not be lost though. With a lot more work, one could probably still find a plug/socket pair which has the appropriate geometry to mount on the board, but one would have to rewire both sides of the circuit. The socket's are usually pretty easy, but redoing 20 (?) pins on a plug can be a PITA.

 

Yeah, I've been quoted $800 from the stealerships more than once... Bunch a criminals! Used to be a used battery ECU sold on Ebay for $50 but supply for Gen2 is dwindling and price is soaring. Wish I hadn't thrown away those first couple fried ECUs.

As for cleaning and reusing an old ECU a friend told me Aqua Net hairspray from the dollar store is a cheap lacquer that would prevent the corrosion from coming back? What do you think?

 

2 years of use with my nickel metal hydride battery pack and all the cells have almost exactly the same voltage. Never seen anything better balanced in my life

 

Well, one could certainly coat the metal with an insulating water tight coat. However, after that one couldn't see if the metal was corroding underneath unless it was enough to displace or discolor the coating. (More or less like rust on a car under the paint.) If the coat was transparent that would help, not sure if any are though. Maybe this one, which is "clear":

EL600 Clear Insulating Varnish | Sprayon

If you do want to try protecting the metal use a product actually designed for the task. 3M makes two types of spray on insulating coating.

https://www.3m.com/3M/en_US/p/d/b00040353/

Google for "paint on electrical insulator" and many products appear. The paint on stuff should be less expensive than the sprays, and probably safer to use, since breathing small droplets of this stuff cannot be a good thing.

 

Thanks for this info... Many of the larger hybrid battery rebuilders claim they offer an "upgraded battery ECU" and have always wondered what that means. Because no one has every announced success reprogramming a Prius battery ECU my hunch is spraying on this stuff after they clean any signs of corrosion is what they mean by upgraded.