Today was my first day to test-drive the enginer kit on a drive to work. I started off in EV mode and drove the 1.5 miles to my daughters school and dropped her off. I still showed a full-charge on the HV battery. I continued onto the rest of the way to work, which is an additional 2 miles. Again, HV battery was still fully charged when nearing my work. Unfortunately, the last 1/4 of a mile is on an access-road to a highway. That is where my job is situated and there is no way around it. Traffic goes 45 miles per hour on that road. At times, there is little traffic on that part of the road, so I could go 34 and nobody would notice. Not this morning, there was a ton of traffic and I'm not going to cause a traffic jam and road-rage. So I had to drop out of EV mode for that last 1/4 of a mile. What a pitty. it was actually very nice and pleasant driving in EV mode the other part of the trip. I know the car wouldn't be able to sustain 45 mph for a long journey, in EV anyway, but being how short of a distance this is, I'm tempted to look into one of those "forced stealth" modes so that I might make my entire journey gas-free.
Nice going! Are you not worried driving around without the BMS? And what about the charger, does it protect against overload without the BMS?
Yeah, honestly I'm a little worried. I'm just performing some test drives, though. I've been careful not to charge the pack up all the way, and I only drive a few miles on it. So I should be pretty safe for these tests. But I won't be leaving the kit on all the time or charging it completely until I get the BMS. In fact, I probably won't use the kit anymore until I get the BMS.
I am a bit weary about using the EV mode; unless I anticipate a lot of stopping so the Enginer can recharge the stock pack. I've noticed that the Prius computer execute the recalibration code (draining the pack to 2 bar then let it charge back up) more often when I use the EV mode. My concern is for the health of the stock pack, granted that 2-bar is still 40% SOC. My 2004 has 160kmile now; out of warranty
I did a 9 mile drive and 90% charge with CellLogs. I was surprised that the batteries started so low. Less than 50%. Be really careful. you do not know where the cells are at until you run them to the low limit and the high limit. Thanks, Dan Lander
Could you clarify that statement? Are you talking about the cells in the stock HV pack, or the cells in the enginer pack? Obviously, the Prius shows me the level of the stock HV pack. PBUI - You talk about pack recalibration. I have not seen that yet. I drove to work in EV mode again this morning (almost 4 miles) and I noticed the HV pack drain down to 4 bars at one point when climbing a hill, but it returned to 7 bars by the time I made it to work. It doesn't appear to be recalibrating. Also keep in mind that since the enginer kit's power passes through the current sensor in the toyota HV pack, the computer knows exactly how much power is going in and out of the system.
The Prius checks the current flow going in and out of the HV pack and based on that estimates the SOC and that is shows as a certain amount of bars on the display. On occasion, I don’t exactly know when, it makes a very accurate calculation of the SOC of the HV battery. That is what is called the ‘recalibration’. The actual SOC may be different to the estimates it made while driving. Last summer I noticed the the SOC on the display was at only 4 bars while my Scangauge told me it was a 60.5%SOC. A few seconds later it suddenly jumped up to 6 bars for no apparent reason. It seems the Prius made a recalibration at that moment. This was in my standard Prius, no Enginer kit yet or other modifications. Why the system works like this I don’t know, it doesn’t really make sense: if my Scangauge can show the real SOC why doesn’t the Prius do the same. And I also don’t know what the conditions are for making a recalibration.
Hi David, I am sorry for not being clear. The RealForce cells were less that 50% SOC when I recieved them. If anyone is running them without a balancer or some way to know the actual SOC then they are very much at risk of dammaging these new batteries. Thanks, Dan
Well, at least I got a tracking# for my balancer. It is coming priority mail so I should have it this week. I'll avoid using the kit until then.
Hi Adric, The 52mph hack may work for you, but i believe you need a scangauge to clear the code before you can drive the car Any chance you could do a video of your drive so we can see what kind of speed/terrain you're on?
The "recalculation" is just to reset the integration, which is numerically imperfect and can diverge. The key word is the SOC is an estimation. I don't think the system knows the real SOC, just an educated guess. I believe the Scangauge just display the serial messages on the communication bus. The recalibration is called for when there is some sort of discrepancy among the monitors. My concern is to minimize the range of the SOC for the health of the stock pack; though I think Toyota is already doing that by keeping between 40-80%. I just notice that the recalibration is more often when i push the EV mode
Right now it is too dark. I had already thought about doing a video once we change daylight saving time.
