Daox's Enginer PHEV 4kWh install

Doax,

Many thanks for starting this thread. I've been waiting/waiting to be able to
follow a DIY PHEV conversion from the git-go. :cheer2:

Why did you choose the 4kWh battery over the 2, 6, and 8 ones offered?

On the balancer issue; could the different cells be balanced separately
by selecting them individually with an A-B switch in the circuit?

Thanks especially for the pix. I'll be looking in on you frequently.

Who knows, if all goes well -- both for your install, and for me --I could be
doing the same in the not too distant future. :rockon:

 

Daox,

Actually I have 4kWh wired in the buddy pairs and the system is much easier to balance. I think this arrangement is working much better than when it was setup with two banks of 48V in parallel. I had lots of balancing issues with the old format using 4 balancers. I have been using the buddy system for about 2 weeks now and have had a very well balance charge and discharge for about 2 weeks. Balancing the batteries is the critical part of this kit. I have 8kWh of batteries but I will be adding the other 4kWh when I feel the system is fairly well balance since it is a pain to get into the tire well with everything installed. I will actually be testing out using 4 cells buddies instead of 2 with 8kWh of batter to see if that will get me a better balance. One advise is to balance at the bottom of about 3.1V at first before the first charge. Balancing at the bottom seems to be safest.


-Chan

-Chan

 

Let the fun begin, eh!

Do you have any kind of a feeling for how long the install will take?

As a point of interest, do the batteries have to be broken-in or
conditioned before use?

"Balancing the cells," how often is that required?
How long does it take -- on a cold, dark windy night?

I am not conversant with matters electrical, :noidea:
so although some of my questions may appear too simple to be true,
I am just keenly interested. :rockon:

 

Hi Doax,

It looks in the pictures like the Batteries are not set up for Buddy cell. So either you need 2 more balancers or you need a bunch of copper straps and cables. Is this true?

By the way Thanks for all the pictures. This is really helpful to us that are planning to do this over the next few months.

I see in other threads that there have been some problems with bad cells. Be very careful with balancing. I am convinced that some users have damaged cells. Do not do unattended charging until you are sure that everything is balanced. The beeps are important. When you hear a beep from the balancer be sure to turn off what you are doing. The system is designed to self correct but it needs Off time to do that.

Please continue to provide Data and Pictures as you do your installation. We all learn from that. I will do the same when I get my kit.

Thanks,
Dan Lander

 

Doax,

What is a "buddy cell setup?"

EDIT: Found it here (need to do lots more reading! ):

http://priuschat.com/forums/prius-p...per-break-in-charging-cycles.html#post1013351

I decided that to get the most benefit from this thread/vicarious
experience, I needed to do some homework...

FWIW to other viewers, the Gen II Installation Guide is here:

http://www.enginer.us/img/Enginer PHEV User Manual Generation 2 Prius.pdf

An installation video is here:

http://www.enginer.us/video1.html

 

Hi Rokeby,
I suggest that you read the following threads
Enginer PHEV Technical Information
Enginer kit proper break-in charging cycles



The 2kwhr enginer design includes 16 cells at 3v each to get 48v total. The 4kwhr system doubles this puting two battery packs in parallel. In actuallity each cell charges to higher voltages and discrages to lower voltages. Voltages of 2.8v to 3.75v are OK. Above or below these levels can cause damage to a cell. The charger will charge to 58v and the converter will drain down to 46v. If all cells are at the same level, then 56v/16=3.63v and 46v/16=2.88v so if all cells are at the same level then you are OK.

However, all cells are not the same. New cells will need to be balanced. In addition, if you have a weak cell it may go up faster and then go down faster.

If the battery pack is out of balance then you can have one cell go above the 3.75v before the chager sees 58v so the charger can keep putting power into the pack and damage that cell. When this cell goes above 3.75, the balancer will beep but will not stop the charging. Be sure to turn of the charger if this happens. Then the balancer will draw 300ma out of the high cell(s) until all the cells on that balancer are at the same level. This will take hours the first time.

A symilar condition happens during discharge. When you are running the car, the pack will go down in voltage until it hits a total of 46v. at that point the converter will shut down. If your cells are out of balance while running the car one of the cells could hit 2.8v before the converter shuts down. If this happens the balancer will beep. At that point you need to shut done the system using the switch on your dash. You can then drive home and charge the system and then wait for the balancers to re-balance the cells.

The balancing process will become automatic once the system has been exercized. As long and you do not have a week cell, you will not ever hear a beep again. However, if you do hear a beep it is important to shut down what you are doing and check the system.

The Buddy Cell system pair cells together. This pair of cells is more likely to stay in balance. The down side of Buddy Cells is that this could hide a defective cell.

Hope this explaination helps.

Thanks,
Dan

 

Dan2|,

Thanks for your post.

I've spent the better part of the day reading the various threads here
on the Enginer conversion.

The balancers are inside the SS case, under rear hatch floor. It seems
like hearing the all-important single warning beep could be an iffy
thing. Any likelihood the beeper could be moved forward to the dash?

From all I've seen, the 4 KwH pack fits under the hatch area floor. Is
that true for the 6 kWh pack too? -- that's the one that would best
meet my needs.

My head is spinning. It will be visions of balancers, kWhs, etc, not
sugarplums that will dance in my head tonight.

 

The 6 and 8 kWh kits should all fit at least in the 2010 prius. I was able to put 4kWh of batteries in the spare tire well and 4 kWh in the steel box.

It is rather difficult to hear the balancer beeps. I extended all the cables for my balancers and moved them outside the metal box so I can hear the beeps and shutdown the system while I am driving.

 

Merry Christmas Doax,
What you are proposing is the same as if you had bought the 2kwhr system. When I look throught all the threads, I get the feeling that the 2kwhr systems have had more damaged cells. I think this is because the charger is putting all 15.5 amps into one string of batteries so they charge faster. This is OK but be sure to pay attention to the beeps. I am pretty sure you will get a warning on the first charge. Just turn off the charger and wait over night. It will self correct.

By the way. New batteries are always the worst for balance. They get better as they are exercized. Out of balance when taken out of the box does not mean they are bad or weak.

Thanks,
Dan