Bus Bar cleaning

As I bust up batteries sometimes I save the bus bars the copper ones I just have them shaken in a brasive cleaner down at the place and they look brand new using again I want to try some of these harder silver metal ones see how they do coppers always going to get dirty after I put the rack together I spray them with the CRC terminal protectant the red stuff it's the light coat.

 

Not another bus bar cleaning post. <sigh> I said it before, I'll say it again. Put them in a rock tumbler and add water and go to sleep. When you wake up in the morning take 'em out, rinse 'em off and you're done. They'll look brand new with a high quality matte finish.

 

I got like 8 battery packs worth of bus bars and I'm about to borrow the rock tumbler from my neighbor again. Do you realize how long it would take to hand clean 8 packs worth of bus bars? Beside you get a 100% consistent finish on every bus bar. No other method does that as quickly.

 

Bench grinder?

 

Grrr....

 

Bench grinder with brass wire wheel.

 

Muriatic Acid takes about 15 seconds per battery. Dissolves pretty much everything except glass, plastic and copper.

Takes even less time if one just uses a new wire frame #2 harness , which also eliminates the chances of failed sensor tabs.

 

And as I'm successfully stocking up on wire frame #2 and am gonna be installing lots of brand new upgraded v2.0 Project Lithium packs in November because they're even higher performance than existing ones, I'm gonna have to start getting rid of lots of unneeded busbars.

 

I will second the Muriatic acid. Had some left over from years ago garage floor cleaning project. Threw the busbars in a small jar with the acid and literally seconds later they looked completely clean. Left them in for 10 minutes for good measure, rinsed off with water and good to go.

 

I have muriatic acid from pool work I didn't even think to use it I just throw them in my daughter's rock Tumblr quickest thing I could think of

 

Rock tumblers are typically run with a mild abrasive. I believe that it will remove a layer of corrosion, but it will also induce a very large number of microscopic scratches. For a part which is coated copper, some of these might be deep enough to get all the way through the outer metal and into the copper beneath. Once the copper is exposed, that section will corrode rapidly. It think this might be especially a problem for flat metal like the bus bars, where the edges could smack into each other, which would magnify the damage (versus flat to flat impact). Is it really a problem? I don't know, but acid treatment will not cause these sorts of mechanical damage. Not that it is entirely safe, it is still possible to burn all the way through a preexisting weak point in the outer layer, or to accelerate the part's aging by thinning that coating.

 

Used fine carbodurum powder soak in acetone after.

 

While I understand the sentiment, the jury is still out on the actual lifetime of Nexcell packs. Conversely, there are 15 year old NiMH packs still in use (one is in my car.) My experience with other Lithium batteries was generally "very short lifetimes", as in laptop battery packs. Never more than a couple of years. None of these were the LFP batteries as used in Nexcell though, and LFP is supposed to be quite long lived. But nobody really knows for sure, as commercially available batteries using that chemistry have only been around for a few years. Also, chemistry isn't everything. Honda Civic Hybrids also used NiMH cells (cylindrical rather than prismatic), and those were far less reliable than the Prius cells. If a Honda NiMH pack reached 7 years that was exceptional, whereas pretty much all Prius packs survived far past that. See the table here:

2015 Subaru Outback and Legacy | Video Review - Consumer Reports

 

@pasadena_commut I have read a few articles relating to the early failure rates of Honda hybrid batteries and they all pretty much agreed that the difference from the Prius models with the same battery chemistry was Honda's aggressive use of the batteries. IOW, they allow deeper discharge and higher charge rates and voltage. Toyota was smart to be very conservative with the useable range of charge that the Prius can use and charge rates.

I've never tested this so I can say for sure, but I have seen reports about it.

 

Cooling may also have been an issue. The design of the pack didn't guarantee that all the sticks were at the same temperature, so parts of the pack could age (due to thermal concerns) at different rates.

Two other big problems. First, Honda did not make arrangements for a continuing supply of the original batteries, so after a while if a pack died they would supply one containing used batteries for a failure under warranty. As you might imagine, these did not last very long. (First hand experience.) The second problem was that the Chinese companies which sprung up to fill this void (also for other cars, like Ford's C-Max) made products which were, for lack of a better word, crap. Or at least, highly variable, which made building a good pack extremely challenging. I bought a pack made with these for our HCH 1, but it failed in two years (-ish, I don't recall now the exact period). No way I was going to spend that much, that often, on batteries.

As I have said before, regarding the Nexcell modules, we also don't know that the NiMH modules Toyota has now are as good as the ones they sold 15 years ago. However, we have reason to suspect that they might be, since Toyota at least cared enough to maintain a supply chain for them.

 

Good idea, fast and easy to do without removing things.