Hello, So my Prius was left for around a year and couldn't get into ready mode after this time: red triangle and P0AFA error. After I removed battery cover I've noticed about half cells were wet on top and when I was removing black rubber vent it was some water (not a lot) coming off it. Now first cell from right is reading 0.03V, and another 11 are reading between 0.1-1V and then another 15 cells were on 7.45V and the last one 6.9V. Obviously battery is dead but my question is how is it possible that some cells remain in good condition and some are discharged to almost 0V? I've noticed water in 12V battery compartment and under spare wheel and I think water was coming through small crack near roof. Could that be a reason of hybrid battery problem? The car was under car cover in hot summer which probably was stupid idea and maybe heat caused that? I don't think there is much point in replacing 13 bad cells?
Welcome to PriusChat!! Please tell us more about this black rubber vent. FYI : you're moderated until you've posted 5 times.
You're talking the Black plastic duct work to and from fan? Or venting tubes long as battery case plugged to a nipple on each cell? Usually leaks are from hatcha areas look at seams in unit construction it's glued like the Black stuff under spare tyre see how it breaks up and rattles. Similar type material fails on between sheet steel . Then water ingress past rubber deal etc.prius is like the Pacer. Fish bowls missing water.
I'm talking about rubber tubes plugged to each cell. It got quite mouldy as well. There was a bit of water in those nippels, those small holes and rubber tubing it self. Also some cells were wet on top (as I marked on picture). Sorry, English is not my first language, I hope you can understand what I'm trying to say ;-)
that's what happens when old batteries sit. i don't think it is part of the roof leak, that is very common. agree on not replacing cells. a new oem is pretty inexpensive these days, or look into 'newpriusbatteries.com'
The oxidation on the rubber tubes is common, though that looks pretty thick compared to others I've seen. No sure about liquid in/on top of the modules/tubing, especially with the cover on. How many miles are on the vehicle? Maybe someone else will know : @TMR-JWAP @ericbecky @strawbrad @3prongpaul @Texas Hybrid Batteries
I'm from UK so I'm afraid that's not an option. OEM battery cost £1450 which is about half of what car is worth so I don't think there is much point. There is few offers on eBay for about £300-£400 for second hand ones, probably worth to try. Mileage is 150k miles.
Don’t confuse what people will pay you for the car vs what it is worth. Used car offers are usually deeply discounted due to the fact that used car buyers are leery of what else is wrong with the car. If it’s just the battery, fix or replace it and move on. Market prices are irrelevant. USD1900 for an OEM battery is not a bad price if you intend to keep the car. 150k is a baby. If you want a new car, sell it and get a new one.
I've seen significant water pooled on top of battery modules a few times, along with water actually pouring out of the plastic ductwork when disconnected. Never had water in the rubber vents tho. Typically, due to rain leakage into the car along the inside of the trunk area side panels. I've pulled those panels off and had water dripping out of the insulation.
I suspect the orange plug at the battery computer for the voltage sensing wires is corroded. The corrosion provided the pathway to discharge all those cells. For more information check out this thread. The battery fires at ECU sense connector thread | PriusChat
Thank you for your replies. I bought used battery from the car with 107k mileage. I've checked voltage on cells and they looks quite consistent except of 1st and last and cell 22. What do you think? Oxidation on connectors is quite bad, should I been worried? I'm attaching photos of cells voltage and connectors.
Interesting how that one cable connector and nut (on the safety disconnect cables) looks brand new. Happens like that sometimes.
@strawbrad I've checked my old battery ECU orange plug and you were right, it was really badly corroded, some pins disintegrated! It wasn't burnt, just very corroded. Maybe a stupid question but can I use Contact Cleaner to clean this orange plug in my new battery? Or would I have to disconect the harness first?
Not a stupid question: be very careful handling that cable or connector; they are live. With the orange service plug in place, there can be well over 200 volts across that plug. Normally, you will have removed the orange service plug, but that still leaves over 100 volts across that plug. And those lines aren't fused, so you could make a good bang or fire if you inadvertently short it while handling it. It's only really safe for handling after its 14 connections to the battery module terminals have been removed (using an insulated socket and your insulated gloves). And at that point, it is just as easy to replace it with a shiny new "wire, frame, #2" rather than trying to clean up the old one. The condition of the orange socket in the ECU also matters. The ECU is safe to work on as long as the connections have been unplugged from it.
That's very common for #1 and #28 to run a bit lower than the rest. It's nothing to worry about. #22 is probably the module that will fail first some day. Not if you just leave them alone. The current flows from the face of the module terminal to the back side of the bus bars. The tension of the nuts provides an air tight seal for those two surfaces. There will be much less corrosion there. Install the battery as is and see if you got lucky.
