ok need everyones expert advice. Heres whats going on. Battery goes from full charge to dead and back very fast. Assuming its a battery issue I removed the battery and volt metered every cell 1 8.14 2 8.14 3 8.14 4 8.13 5 8.13 6 8.13 7 8.13 8 8.13 9 8.13 10 8.12 11 8.13 12 8.13 13 8.13 14 8.12 15 8.13 16 8.13 17 8.13 18 8.13 19 8.12 20 8.13 21 8.13 22 8.12 23 8.12 24 8.14 25 8.13 26 8.13 27 8.14 28 8.15 So Im at a loss. now what? Please help.
How long have you had the car? I ask because if its new to you, it could be that the battery just isn't living up to your expectations, not necessarily that its bad.
Almost 2 years. Normally it's fine however the last couple of weeks at a stop light it acts like it has no power. I know because when the battery is showing charged it drives like normal.
sorry, no. but i'm sure someone will. weekends can be slow and people don't pay as much attention. hang in there!
So when it's acting like it's got no power, what is the displayed state of charge (number of bars). It certainly could be that your battery has lost some of it's capacity (amp hours), but as long as there's no actual failed modules the voltage would still measure ok.
1 or 2 bars. I can't remember but what ever the lowest is. I agree that it may have lost capacity but even with it "low" it's still in the 80% charge zone right? But it hardly goes. The motor reeves and the car hardly goes.
No it's about 40% at the lowest bar. It's not really the exact amount of charge that's important though, it's the fact that the Prius wont use it (when it's low) that makes it sluggish. Mine is also really sluggish if the SOC drops to red (2 or less bars) so I think that's pretty normal. The real issue to look into, is what's happening to make it that low in the first place (which certainly could be a low capacity battery). I find that if let my engine warm up (idle in "P") for about 60 seconds before driving that the battery charge stays a lot higher. Are you noticing these issues predominantly soon after starting, or do they persist even after a long drive?
After a long drive. Not so much at start up. We can be driving for a hour or so and it will start doing that.
Are you still under warranty? If so, I'd be pushing it hoping it will throw a code that will convince the dealer to replace the HV battery pack for free. The code is triggered when one of the banks voltage is greatly different from the average (I think 2 volts different). I would guess that is more likely to happen when the battery is charging to full, quickly depleting and then charging again. This is just my speculation though.
What warning lights appear? If there are no warning lights then it is not obvious the traction battery has a fault.
As I mentioned on your other thread, this sounds to me more like an overheating issue. Possibly battery fan related.
Yep, that's exactly what I was thinking, once we knew it didn't happen until after it had been driven for a while. Itwrx, take a look at this thread: Fur and dirt causing major battery problems | Page 2 | PriusChat It would also be a good idea to make sure you inverter coolant system is in good shape.
So I just came in from taking apart the entire fan system. It was spotless. Im wondering before I took out the battery I had the car running in my driveway for about 20-30min with the heat on. Its snowing in Park City and i wanted to work in the warmth as much as possible. Could that extra 30min of charging affected the bad cell assuming I have one? Lets say one or two cells have lost their ability to store amps. I know through my RC car experience a battery may read 7.2V but can only run the car for a min where a healthy battery will read 7.2V and provide 15min of running time. Since the battery is out and disassembled is there a way to find the week cell?
No, that won't have hurt it. Yes, that's what happens with series batteries. Once one loses capacity the whole pack effectively loses capacity. With the Prius however, it monitors all of the module voltages and will set off an error code if the pack gets too far out of balance like that. I'm not sure what you can do short of doing a discharge test on every module. If you're really keen you could get hold of some chargers and try re-balancing the whole pack. If you do a search here there are several threads that detail how to re-balance a pack.
I think you would notice a bigger difference between the cells if the battery had a low SOC. I wouldn't get it too low, maybe 4 bars and then check it.
Yes, you would need to fabricate a suitable load. Since the battery will produce ~200V you need a load that will handle that voltage and also absorb sufficient current. For example, buy four of the largest incandescent light bulbs (intended for household usage) that you can purchase along with suitable sockets and wire. Suppose you can purchase 250W, 120VAC bulbs. Wire the four bulbs as two pairs. Each pair is wired in series because the bulbs are rated for 120V. Then wire the pairs in parallel. The four bulbs collectively will absorb 800W or so. The power consumption will be less than 1kW because the battery voltage is lower than 240V. Then you need to connect the bulb load to the battery by bypassing the system main relays, without causing damage to yourself or the battery. Once the bulbs are lit, you can measure the voltage across each of the 28 modules and see if one is lower than the others.
Ok so let me make sure I understand. After I hook up 4 bulbs and power then for 10min. I take the battery apart and mesure each cell individually right? Also someone had mentioned I should get a ScanGuage II. I found one online used for 100.00 Is this a good tool to have or not?
