I've lurked for a while & think this is the best place to post my question. Please let me know if I'm in the wrong spot. My 2001 Prius has 4 or more dead cells in it. I've been exploring my options (ReInVolt, Toyota, rebuild myself) but a new one dropped in my lap today. A friend totaled her 2005 Prius (she's fine!) and said I can have at it. I've heard all over the place that a Gen 1 battery can be replaced with a Gen 2 battery. I'd like to know what components besides the battery I need to yank out. I'm comfortable with the voltage & multimeters & the service plug concept. I've never worked on a car outside of an oil or headlamp change, my comfort level comes from working for years with 14000 DC voltage in a lab with lax safety oversight (on the job training at it's best!). ps I thought I was in the Gen II Tech Discussion, would a mod be kind enough to move this?
Well, let's start by clearing a couple of things up 1) Gen II modules can be used to replace Gen I modules but the Gen II battery is not a direct replacement for the Gen I battery Why? The Gen I battery uses 38 modules in the battery pack whereas the Gen II uses 28 modules. In order to build a Gen I battery using Gen II modules, you will need two (2) Gen II batteries then you'll need to find 19 matched (matched in capacity) module pairs (38 total modules) that are also voltage balanced w/in .3V's. Those modules will then need to be installed in the Gen I pack and the pack placed back in the car. It is something that can be done but the procedure must be clearly understood. There are numerous posts on PC discussing this.
It would also not be a good idea to mix gen1 and gen2 modules in the gen1 pack. Although similar in size the gen2 modules have lower in internal resistance than gen1 and are also likely to be of higher capacity. This would likely bring about reverse charging of gen1 modules in such a mixed battery pack. John (Britprius).
I just got back from taking a look at the car. There was too much rear end damage for me to feel okay about the battery pack. Not that it looks like I'll be doing it this time around, but do I understand correctly from my other reading that a Gen 1 pack can have it's cells replaced with Gen 2 cells but no other components need swapping out?
Your understanding is correct but the modules (6cells to a module) must all be balanced as close as possible for amp/hr capacity and very closely for voltage.
May I suggest that even if the battery pack is damaged you salvage it. The reason I say this is because it contains 28modules and even if half these are damaged (unlikely) that still leaves 14 good modules. If you purchased a complete gen2 battery from a breakers yard you have enough modules with spares to rebuild your gen1 battery.
I've offered to help my friend's husband salvage parts since I'm comfy with the voltage & any possible chemical leaks. He's much more the car guy than me so I'll let him figure out what the parts are, test them & sell them himself. But when I say the rear end had too much damage, I mean she was slammed into a telephone pole after getting T-boned at 55 mph & she hit it right at the passenger side rear wheel well. From what I could see the battery pack was at least partially smashed. I'm expecting that when we get into it (assuming the insurance company gives us the green light) that there will be a good bit of leaking fluids & therefore possible shorts. I had a transmission issue that got me to take my car in for a check so I've got a call in to Toyota to see if they'll help me out. I've asked that they buy back the new battery if I get it fixed and then need another $3k worth of work. I should hear back from them Wednesday & I'll decide which way to jump then. There are no transmission-related codes showing up so I hope they'll bite.
The battery pack contains very little fluid but beware it is basically caustic soda wash with plenty of water and vinegar.
The KOH electrolyte feels 'slippery' because it converts oils into soap. Make sure you have an eye-wash kit and safety goggles . . . and clothes you don't mind if they get holes eaten into them. How do I know? Bob Wilson
The Prius battery is in a very safe location of the car. I've seen cars pretty smashed up, the battery enclosure may have dents but the cells inside are usually fine....and like Britprius said, even if you only get 10-15 slices out of it you now only require one other Gen2 battery to rebuild your gen1 pack. How many miles on the Gen2 and where is the car located? Maybe someone on PC will offer to help with your project if they are close.
i've been picking up gen. 2 batteries for $350-$450. i suggest taking the free battery from your friend and go to car-part.com and find another salvage one close to you. after you have your battery rebuilt you can sell your extra 18 modules for about $30 each as well as the leftover gen. 2 battery casings. that should help cover the cost of the job. you can ask on here for someone to help you in your area. good luck!
