New OEM hv battery post stud snapped

You cannot buy 2 new modules, you would have to return the battery for another one. I think an understanding person at the Toyota parts counter will be able to exchange that for you. If the person is an older person at the parts counter, tell them you ate some spinach right before torqueing the bolts (hopefully they get the joke)

No you do not want to mix 26 brand new modules with 2 used modules, that's just asking for trouble.

 

60-in-lbs is the wrong value.

You cannot buy 2 new modules. The whole problem I solved was because Toyota does not sell new modules individually.

You may be able to lie your way into a new battery with the dealership, but really since you broke it they don't have to give it to you.

As a stop-gap you can use some used modules, but now you have a used pack. You're going to be playing whack-a-mole from the beginning which offsets the reason to buy a new pack in the beginning.

Your second best option may be to buy a couple Yabo modules. They are form-factor compliant to the PrimeEarth's but they are crap. They're better than any used module you can buy, you should be able to get 4-5 years out of it.

 

This makes no sense because a brand new pack comes with new bus bars and wire frame already bolted to the modules? Why would you replace brand new with your old used ones? Or maybe you're referring to the bolts where the module mounts to the chassis? but again that all comes pre-mounted?

If your efforts to get a new pack with the dealership fail, which seems likely, I'd recommend you find someone with a drill press/machine shop and drill a small hole in the terminal posts and reattach the snapped off posts with a small screw and a bit of solder...

 

Can you say more about where you got this 60 in-lb figure? It's the wrong figure, which is why they snapped, but if you found it in some source that others might stumble into and rely on, maybe identifying it here will save someone else the same grief.

It could also be worth mentioning that when we talk about the size of a bolt, stud, or nut, we give the diameter of the threaded portion, not the size across the hex head or nut or the socket size you would use to turn it. If you would use an 8 mm socket to turn some bolt or nut, one thing you know for sure is that is not an 8 mm bolt or nut.

 

If the two (2) brand new modules aren't saveable, then reach out to @TMR-JWAP and ask for 'newish' pair to them replace with.

 

Couple things here.

1. You need to check whatever tool you were using for torqueing. There's no way a true 60 inch pounds (5 ft-lb) should snap one of these studs. I've tested them at their weakest condition (with no cable or busbar attached), and it took ~110 in-lb to cause damage. The torque spec is 48 inch pounds (4 ft-lb) but I use 60 quite frequently and have never had a problem. I've seen several youtube videos that discuss using 60 also.
2. If you need a couple modules that near the capacity of a new module, I can help you out. A new module is rated at 6500 mah, but usually tests in the 6900-7200 range or better, when new (using my methodology). Using the same exact methodology as I used for testing new modules, I have many modules that test to a similar range and should be effectively indistinguishable during operation.

 

I have a drill press and wondered about the drilling out option. Wasn't sure if standard rosin-core solder could handle the current and temperature? And concerned about how much depth there is to work with.

Please don't do this. It's a catastrophe waiting to happen. I have a Gen2 battery where the original owner accidently broke several studs using a ft-lb torque wrench instead of an inch pound while attempting a DIY rebuild. Mistakes happen. The problem was multiplied when they attempted to drill all those broken terminals so they could just screw into it to mount the busbars. It doesn't work and makes a holy mess of everything. It effectively turned that entire battery into scrap.

 

Any chance you did foot pounds??

 

Whenever I use T wrench I always check it out on a tire lug nut which can handle lot of torque. It’s a wrench most people don’t use often easy to set it up wrong.
Some t wrench’s click when torque reached some like my craftsman just do a subtle release feel have to pay attention.
On this battery I would not use a bigger socket wrench than a 1/4 inch.

I always thought a factory Toyota battery came with all the battery’s installed and assembled already.
What new battery did you buy and where and how much please.?

 

You can also get T-handle wrenches, preset to low torque values. I think they just slip once torque is achieved?

 

Don't worry, I'm not laughing, just trying to help figure out where incorrect information is being found so we can make it easier to avoid.

It's an easy mistake to make, but it can have disastrous consequences if somebody uses that size to search in a generic table of torque limits by size.

The most important point there is that, yes, the torque spec is 48 inch pounds, from the Prius repair manual:



The fact that there might be "several youtube videos" (or their attached PDFs) that give different information is a powerful reminder of why important things should be looked up in the manual.

If the nut size fits an 8 mm socket, then the stud is an M5. If you go looking for M5 in just a generic table of torques for graded steel fasteners:



you would find that for a class 5.6 stud you wouldn't go over 1.99 foot pounds (less than 24 in lb), and even for a class 8.8 you wouldn't guess more than 4.54 ft lb (less than 55 in lb). I copied the untreated/black section of the table; the torques in the zinc plated section are slightly lower.

Of course generic tables like that are published for steel fasteners that are strength-graded and meant for structural assembly. The studs on a battery module are going to be made of some material chosen for its electrical properties more than its structural strength, and there aren't likely to be generic tables showing their torque limits. That's the kind of situation where it's critical to use the information from the manufacturer about the intended torque. Specified torques are a bit conservative, of course, to have a safety margin. One might have used a higher torque "quite frequently" and even gotten away with it, but that isn't a good reason to make new readers sort through conflicting information about what the specified torque is.

 

Ah yes. Perhaps you mean the infamous "I bought the most hated car on the internet and made $1000.00" with over 6 million views now. He takes a bunch of used modules, calls them "rebuilt", claims he was told they will last 6 years, promotes the "rebuilder" company, and links to the installation document provided by that company, which lists 60 inch-pounds as the torque spec.

 

Considering the costs and ramifications, maybe these rebuild kits should come with a t-handle 48 inch/pound torque driver, the kind that slip when they reach target torque. They likely wholesale for something like $15. Or at least have them on offer, part of an install kit.