Enginer kit proper break-in charging cycles

Thought I'd try creating a new thread so I don't bother the rest of the people dealing with other issues on the Enginer kit. I've been trying to follow Jack's and Joanna's (Plugmein2) advice and nudging my 2Kwt pack up.

Previously, I was constantly plugging and unplugging the kit for 2 hours. Then letting it balance, reporting the readings, then rinse, repeat. Today, I've been watching it like a hawk, trying to get the overall (lowest cell) up as high as possible so when it balances I end up with a higher pack. After 2 hours I checked on it, and every half hour thereafter. I'm now at just past 5 hours charging straight through. Strangely, each time I've checked on it, it's becoming more and more balanced while still plugged in!

Could this actually mean that I've properly broken in the kit and if so how come my highest cell is 3.397? I figured out that 3.7 is considered high but what is the optimal range to keep the packs charged too? Thanks!

3.75V is when the Balancer will alarm, which is 90% SOC. 3.40V is only about 70% SOC. What is your lowest cell voltage?

Thanks for responding!

My lowest cell is 3.3 something. I just unplugged the car cause it's now 6.25 hours and it's making me nervous leaving it plugged in. One of the balancers is now showing a zero, I tried pushing the start/stop button to get the readings and it won't do anything, the other is showing a .011 as the last number and it's high and low are as well in the 3.3 range

Do you have a digital voltmeter? You should verify the readings on the balancer with a voltmeter. It could be that the actual readings are higher. Or it may be that you have to cycle the batteries before you will be able to get to a higher capacity. If you have had them charging for 6 hours, they should be fully charged by now.

5 hours seems like a very long charge for a 2kw system.

Are you sure your charger was working? Did you hear the fan running while it was plugged in?

You might want to try swapping the balancers and see if the one giving you a zero does the same thing on the other set.

Last time I checked on it again, same thing, still showing a zero on one of them. So, I unplugged it and plugged it back in. It did it's LIFE thing then I pushed the on/off button once and it cycled. That one is staying in the mid 3.3's pretty much, it had a variance of .025 The other one was pretty much blank and lit the red dot off and on. It had a variance of .007 or so. So, I left it unplugged and think it's okay for tonight I suppose.

I've decided I'm actually going to do a forced trip in traffic at rush hour so I can get a better idea how it performs under normal every day conditions most will encounter. I looked at the clock tonight and said to my roommate "Oh darn, I missed rush hour" I don't think I've ever said that before in my life.

I don't think anyone in LA has said that til now

lol!!!!!

Today, I had to use the freeway but there wasn't any traffic I'm trying to do that pulse and glide thingie. I am noticing now that I can stay in EV mode a lot more on city streets with even slight uphills under 40 mph if my Enginer is fully charged. Feels awesome, like an electric car, but then today, I did a lot more driving then usual, and had the air on and it was warm (86*) and eventually I got the 3 beep alert that I was running low on juice. So, I turned it off. I kept trying to turn it back on after I thought it charged back up again, but it kept running out of juice.

So I left it off. It felt like eating a great ice cream cone and then all of a sudden your tongue pushes the ice cream ball out and onto the concrete. Party over. Drove home as an ordinary great Prius. Not exactly turning back into a pumpkin, but I did loose my EV grin.

LOL!! I know exactly how you feel. It is such a wonderful feeling driving in EV. It is so smooth and quiet. When the ICE has to come on, I feel a jolt then rumble..rumble of the gas engine. It makes me feel like I have been transported back to the 19th century. "Beam me back Scotty!" heehee.

JOANNA

Christ Dave. Are you going to thank me for this post too?

LOL, I thanked Dave for thanking me, then noticed he's really big on thanking everyone. Thought I was special! But, no. He's thanking others behind our backs! Oh the humanity!

Back when my pack was working, I couldn't get it to charge any cells more than 3.45v or maybe 3.5v tops, and that's after leaving the charger on overnight. My understanding was that it would charge to 3.75 before stopping the charge.

I can't figure out how to modify/program the balancers such that it will charge a little more. The cells are rated 2.5v to 4.25 or something, so it should easily be able to handle a regular charge to 3.75v.

The balancers alarm at 3.75V (High) and 2.8V (Low). There is no way to modify them because the batteries may be damaged if you exceed those levels.

I am new to LiFePO4 cells.
I am trying to understand the charging of these too.
0% capacity voltage is?
LOW capacity Voltage is?
Full capacity Voltage is?

I know that 3.0V is lowest I want to go with LIpo cells. I know that 4.2V is full charged.

I know that LIPO cells are listed as 3.7V, but I don't know the stats for LiFe PO4.

For the enginer pack I want to go to only 70 SOC to get more life out of the cells and want to know how to explore and manage to do this?

Can we set the alarm to go off at that range or voltage or know if it is possible?

I don't think that the alarm ranges are settable.

For cell specs, charge and discharge curves, see my album:
PriusChat Forums - krousdb's Album: Enginer.us PHEV Conversion

Hi, This is my first post. I hope you can help me with my charging problem.

I can't charge my Enginer 4kwh kit for more than a few minutes before several of the cells exceed 3.7v. When I unplug my charger and turn my Prius on, those same cells that showed an overcharge state will drop to below 3.0v within a minute.

When I plug the charger back in, the low voltage cells return to 3.3v within a minute or so. If I leave the charger plugged in the same overcharging will occur.

I have other details relating to this problem but let me start with this.

Anybody also have a similar problem when they first got their kit?

Any idea why this is happening?

Thank you.

Disclaimer: I don't know anything about the Enginer kit

In general, this could be a sign of bad battery cells.

Hi Bob64, That's what I'm thinking but if that's the case then I would have at least ten cells that are bad.

Isn't that highly unlikely from a new kit?

Do you happen to know who makes the cells? How many cells does the kit have total? Depending on the quality control process of the manufacturer - and how good the chemistry of the cells inside, the lifespan may or may not be high as expected... plus a high failure rate is also possible.