Is adding a second battery possible?

Using a pool water pH test kit, I only found KOH around the terminals and nothing in the pressure relief tubes tested.

Bob Wilson

 

Thanks Bob, so the pressure build up was enough to force the KOH out through the terminal seals ..... that was my original guess. If the relief valve had worked to release the excess pressure then there would have been signs of KOH in the vent tubes as well ,,,, the escaping gasses would have carried some vapour with them.

I guess my first piece of investigative work will be to cut the valve out of a stuffed module so I can see just how it is constructed and see if I can use this as my access point to bother deliver the KOH as well as the gas vent. I think I could make a connection that would hold 80 psi, but I think I might drop that to around 50 psi and see what affect that has on charging rate v gassing.

T1 Terry

 

I had noticed one of the two terminals ran hotter during charge/discharge. My hypothesis is the heat softened the "O" ring and plastic enough that it released first. I too endorse using the vent tube for adding water AND some form of external pressure control and/or gas recovery.

Speculation, some form of external gas holder like a cylinder with a couple of CCs of space clamped to the pressure relief vent. The extra volume will reduce peak pressure and mitigate some of the gas loss through the weakened seal. Some experimentation will be needed.

GOOD LUCK!

Bob Wilson

 

Well that is just short sighted and stupid on it's face.
Caustic solutions can be just as dangerous as acid ones.

Adding a caustic solution to another unknown solution is almost NEVER a good thing for a "novice" to be doing.

And just because you haven't personally seen the results of all the hairbrained things that have been tried over the years does not mean that they haven't happened.

But if you enjoy tinkering with things like this, more power to you.
My fear is that someone with ZERO knowledge and close to zero common sense will embark upon an "experiment" of their own and end up with a disaster. That happens all the time.

 

Some of my more sensitive ginger friends would not be amused at the reference to their gender, I'm pretty sure. Might not even like that I liked your post, either. Oy!

 

Wow, I thought it was only the Ozzie forums that attacked from the sidelines ..... the actual ratio of KOH to water isn't like it would be flesh eating or something, but if the joints weren't secure then there would be quite a bit of the solution would leak out due to the pressure involved.

As for someone who didn't know what they were doing tackling a project like this ... it simply wouldn't happen, I'm not producing a step by step process to do the upgrade so I doubt they'd even be able to get the original battery out without zapping themselves ... the 200 plus volts DC certainly hurts enough to let them know they've done something dumb, if they continue after the first zap then Darwinism will most likely come into play and remove them from the gene pool .....

T1 Terry

 

That theory is only valid up to the point where the gene pool is SATURATED with morons.
As each day passes, it looks more and more like we have passed that point already.

 

T1 Terry

 

'ignore' is your friend

 

Wow that a useless thread this is. All the naysayers in the PHEV forum. It looks like a number of people have successfully done it. And now that gas prices are through the roof and the gen2 Prius is so cheap and already has an electric motor and inverter etc. WHY WOULDNT YOU DO IT! It seems you can install a lifpo4 battery pack with the right number of cells and fool the battery ECU with a simple board that you can make yourself from files on this very forum.

 

The attitude here is sour grapes due to historical bad experiences with unreliable junk PHEV conversions.

Members goals are to prevent people from spending more money to convert than a complete car costs to get something limited and unreliable.

As long as you have the $$$ adjusted expectations and want to do it for fun have at it.

Proper conversion of even an antique Prius was definitely possible but rather complex, then Enginir came along and ruined everyone’s opinion of the matter.

There is a so called open inverter forum that has devices to directly operate the Prius motors and systems for the purpose of converting to an engine free BEV.

All I will say on the matter is don’t expect someone to hold your hand, you need to review their documentation and have a plan then ask pointed questions to said group, if they don’t think your “familiar enough “ with the subject matter you will get similar bemusement.

Check out

diyelectriccar.com

https://openinverter.org/forum/viewtopic.php?t=228&start=125

they can help if you have a complete project plan and a list of parts and their cost.

Have fun

 

looking forward to seeing your finished product. of course, anything can be done, but talk is cheap. only the best and brightest can pull this off on their own, i hope you are one!

 

Gas prices are over $5 now when a year ago they were in the $3 range so maybe I'll buy a Prius.
So here's a Prius for $300. Cheap!
Now I bought a Prius, but it needs a new catalytic converter and just last year my state decided it has to be California complient.
Wait! The engine is also burning oil, so possibly a new block since you can't bore these.
And the HV battery is dying, so I'll just replace that too.
But why replace it with an OEM NiMH battery when I know I can get LiFePO4s to work.
For only $10,000 and 364 kg I can add 70 EVE cells and get 62kWh (49kWh usable).
Wait, am I saving any money yet?

 

First question I'd be asking in regards to the oil usage, are you sure it needs a new block? or even new rings? Could be valve stem oil seals that have simply died of old age. The question then is, do you have the skill set to do the mechanical work? If you don't, maybe you shouldn't have bought a $300 Prius :lol:

This sort of experimenting only works if you are competent to DIY any work required. If it had a dead CAT and a sad ICE, I'd be looking at converting it to full electric with an additional motor to replace the ICE so the speed and torque was still available ..... anyone have any links to where this has been done before?

T1 Terry

 

I like you have likely noticed 15 years of people talking about the openinverter controlling a stock Prius sans gasser, lots of folks testing it blinking lights even spinning a motor on the bench. There are directions for each Gen regarding the requirements to get the planetary locked up for EV use.

But like you can’t say I can list a single build thread using it.

Seems like a stick in arse series of super sensitive profiteering individuals hiding behind an open source product being marketed through retail channels.

Damien was always respectable, gotta wonder what happened to the diy movement, now that things are easier than ever there are fewer build threads, only one I remember recently using openinverter is a RWD luxury car conversion.

Given it can control Prius, leaf and volt systems you would expect more excitement, maybe a case of discord servers destroying a community?
Or just another one man show with a bunch of incomplete builds by others?

 

see Converting Prius G3 to all Electric removing ICE | PriusChat

 

Haha! I was trying to make the point that EV conversions aren't always cheap.

I have rebuild one engine by myself and have helped done others. I've been super busy, so it's the time that mainly hasn't allowed me to work much on my Prius. The first step for me is to scope the cylinders and just see if they are damaged. My experience is, it's the piston rings. Not that it couldn't be a valve step seal, but it hardly burns oil at low throttle but burns a lot more at high throttle. If it were anything on the intake, such as a valvestem seal, it should burn more at low throttle and not hardly any at high throttle as you lose intake vacuum.

Interesting. The only problem I see is it would still be coupled to a sort of contiuously variable transmission which wouldn't be ideal for an EV. Maybe if I welded the planetary gear set together into one spining ring, that would solve that. Then the primary motor could work as a motor without the need of an external one. The problem is finding BLDC motor controllers for those kinds of voltages.

Anyhow, I couldn't do a full EV, as even 300 miles of range wouldn't get me where I need even with DC quick charging. The car would have to be a secondary car only, which is not what I have planned at the moment.

 

Isaac the purpose of open inverter is to reuse all the OEM components

AKA You don’t need a controller

You would need a battery bms and charger plus an open inverter control board

 

Thanks, I have no issues making the lifepo4 battery pack with appropriate safety and balancing systems in place. As i have experience here. Its just recreating Norms hybrid interfaces BMS2 board that is new for me. But all the files and data are there and it makes sense the operation of spoofing the battery ECU which will cause the Prius to make use of all that extra battery energy. It seems to be a very proven solution from from what i have read and others on this forum. So i will endeavour to keep you all updated.

 

That's cool! Sorry, I didn't read through everything. But that's good to know, as I wasn't aware of this project.

Yes! That would be nice to know how it goes! For me I've thrown around the idea of replacing or adding a LiFePO4 battery but am afraid I live in too cold of country for it to work. -30 °F doesn't seem to kill NiMH batteries, but it probably isn't good for LiFePO4s.