hybrid to mild phev conversion?

[dluck]

I'm sure people have done conversions of their nonplugin-hybrid to plugin without the extra battery expense. What were the results. On our C-MAX we come home with the battery at about 50% charged. What if there was a trickle charge circuit that could be added that would make sure the EV battery was topped off before taking it out again. Not looking for a quick charge so hopefully heat would not be an issue. I'm thinking that being able to start out every morning with a fully charged EV battery, thanks to the electric grid would be a reasonably good ROI.

[RedDevil]

I'd like that too, if just to balance the cells in my battery pack. Over time the load level between individual cells in the battery pack will start to differ; while some are almost empty others will be full. This will reduce the effective range of the battery pack and may damage the cells as they get underdepleted or overcharged.

A gentle overcharge may top off all cells while those that are already full will not get damaged. A trickle charge will not only give better initial performance, but better performance all round.
It's the not knowing how to that's holding me back for now.

[Cobb]

Long story short, no.

Enginer made a phev kit for various hybrid cars and suvs. In my honda insight I managed a top of 103 mpg, about a 4 hour run time, 5 hour recharge time. Epa is 43.

Even though I got a later more advance kit, it paid for itself with supreme mpg, but it too died due to quality control issues.

As for precharging your own hybrid battery, it helps if you are in a mpg contest, but on a daily bases it will help your pack fail faster. Batteries lives are measures in cycles from being recharged and discharged and to what extend.

The reason your battery is low when you come home is likely so the car can use the extra fuel burned for cold start up to recharge it the next morning. Your cars computer likely only uses 60% or so of the whole capacity of the pack, so it can be cycles thousands of times in daily use.

As an Insight owner and like many other insight owners it seems the least you use of the IMA system the better your mpg is.

[George Tyler]

Originally Posted by RedDevil

I'd like that too, if just to balance the cells in my battery pack. Over time the load level between individual cells in the battery pack will start to differ; while some are almost empty others will be full. This will reduce the effective range of the battery pack and may damage the cells as they get underdepleted or overcharged.

A gentle overcharge may top off all cells while those that are already full will not get damaged. A trickle charge will not only give better initial performance, but better performance all round.
It's the not knowing how to that's holding me back for now.

I have tried this with my Prius, a charge at a low rate (100mA) does not equallise the cells, it actually seems to make them more unequal...which supprised me, I think it is because the self discharge is so temperature dependant and the most full cells get warm and end up the lowest.

[Cobb]

You are right, it does not work on the prius cells. It only works on the cylinder cells. The charge used is 350ma, which btw is what most wall warts use to charge nicad batteries. The non US models had a charger included in the trunkthat did something similar in a different way to revive a low or bad pack.

[RedDevil]

My plan was (you talked me out of it) to trickle charge it every once in a while.
I suspect my pack is not entirely fresh; strong support is always short and never full up the blue side of the charge dial; doodling in EV is only possible for a few hundred meters, no matter how careful. Never had an IMA failure yet though, no positive/negative recalls or what.

[Cobb]

RD, you are in Europe, I was of the understanding you guys had ready available adjustible power supplies and it was just a matter of hooking one up, setting it to 134 volts no load and 350 ma output and wait 36 hours.

Its likely your 12 volt battery that is so-so. I bet if you switched it out you see a vast improvement in your IMA behavior.

[RedDevil]

Yup, they grow on APS trees over here but we're out of season right now
Well they might sell some over here, just don't know. My brother-in-law is the expert on stuff like that, but I'm a bit wary since he all but disected me over my WAI, LGB and block heater experiments. Better know what I'm asking before I do.

You made me realize that while I (like you) told others to test the voltage of their 12V battery, I didn't follow that advice myself even though I did on previous cars and all the bikes I had. Will do so tomorrow.

One map light left on accidentally ran my battery flat in just 10 hours or so. I did not expect that to happen as my car was barely 1 year old .
It won't happen again as the map lights are now LEDs. I rely on my ability to make the same mistake twice .

[Cobb]

Yeah, online it seems those over seas have one laying around inaddition to a scope to look at waves. Maybe one day I can go over seas and see how life is really like and what quarks exist inr elation to the US.

I had a 10 farad cap with voltage read out and subwoofer with amp attached to my Insight. Its connected to a remote wire and i turned the key on one day without starting it and saw the voltage tne next morning was 11.7 volts. I had connected the battery charger to my car other night and thought i had fixed it. It was warm again for a few days, then BOOM, 20 degrees out F. I had to use my key to unlock the door, then 5 seconds later the alarm went off and it wouldnt start. I checked the cables again, nope, had to jump it. Previously I lucked out and fixed it by readjusting the battery cables.

[George Tyler]

Originally Posted by Cobb

You are right, it does not work on the prius cells. It only works on the cylinder cells. The charge used is 350ma, which btw is what most wall warts use to charge nicad batteries. The non US models had a charger included in the trunkthat did something similar in a different way to revive a low or bad pack.

I have 3 of the NHW10's imported from Japan, they have "D" cells. I have been working on the batteries, replacing cells etc as they were not supported by Toyota here. (New Zealand). recently, toyota have started supporting them and I have bought a new pack for one of them from Toyota. The small 12V charger you talk about only charges the pack to enable the car to start if it is left standing for a long time. The "D" cells do act very differently to the prismatic ones, if you charge a totally flat D cell carefully it recovers full performance, but the D cells don't. the D cells in these are 16 years old and have done 300,000 km or 200,000 miles, the self discharge rates have increased on some cells to the point where if they stand for a week they are flat.