Grid Chargers, just a thought

It a car dammit.

You make a good point, but
if the gov gave out incentives for prolonging the life of hybrids
dealers would be all over the charging/balancing it's packs just to see how long they actually would last when properly handled.

And considering how many prius are on the road and how many reports of pack deterioration there are in this forum, it doesn't seem to me like gird charging is all that much in demand, until your pack throws a $3 or $4k code.

 

I believe the assertion of longer life is unproven. There is substantial variability in individual traction battery service life. It is unclear what will help or hurt.

 

I think it is perfectly reasonable to expect a battery consisting of 168 cells in series to be out of balance after prolonged use. Leaving the battery out of balance risks at some stage one or more cells getting to the point where they become reverse charged. This will destroy the module (s) the cell(s) are in needlessly if a balance charge would have bought them into line.
Doing a balance charge occasionally to to help remove the likelihood of this happening must improve the average lifespan of the batteries. At what point re balancing should be carried out, and how often is open to conjecture. However there will always be batteries that will fail early.
A few years ago I asked here on PC about this subject and there was little or no enthusiasm for such a charger. Things now seem to have gone the other way.

John (Britprius)

 

Because a few years ago, few owners thought that their traction battery might actually fail. They believed the Toyota marketing message that the battery would last for "the life of the car" and didn't read the fine print that Toyota's idea of vehicle life was 180K miles. They also noted Prius in taxi service logging 300K miles plus without battery issues and thought this would apply to all batteries, without considering that there is a time variable driving the risk of failure, not just a mileage-related variable.

Now enough failures have been reported so it should be clear that traction battery failure will happen, sooner or later. In my case, if it happens then I will just replace the battery. The 2004 has logged 184K miles...

 

To me it sounds logical that grid charging could help. The data just isn't out there yet JC. Need more time and more info.

Why everyone continues to focus on traction battery when so many other things go wrong on a Prius is amazing. It is a machine. It is man made. It will break eventually.

Use it like any other machine, maintain it and replace as needed.

Ron (dorunron)

 

While the chargers are new and seem unproven to most Prius owners, they have been widely used in the Honda community for years. We have sold over 800 of them in the last 24 months, and we have a >95% success rate at extending the life of a NiMh hybrid battery. With deep cycling, the improvement is significantly increased, as not only is the battery re-balanced, but lost capacity and performance is recovered.

It's the same principle as the many Prius owners who are deep cycling individual modules of their aged packs using the hobby chargers, just scaled up to the battery level. Nothing different from what the Prius community has been doing for years except the significantly reduced amount of labor required.

 

I can well believe that the Honda hybrid owner community is scrambling around to find a solution that promises to increase traction battery service life, given reports such as this:
Honda Civic Hybrid Battery Reliability | Hybrid Batteries - Consumer Reports News

Since the Toyota traction battery demonstrates substantially better service life, its not clear to me that it is worthwhile to spend $400 on a charger. Also, I already have the necessary test equipment available to produce ~220VDC with regulated current flow.

Use of this charger is somewhat like the question of replacing transaxle ATF at 30K mile or 60K mile intervals although this is not required by the Toyota maintenance schedule. To me, the transaxle ATF change is a no-brainer considering used fluid reports that show substantial Si and Fe content, especially since it costs me only ~$40 each time I replace the transaxle ATF. However if I had to pay $400 to replace the transaxle ATF then I would think carefully about the alleged benefits vs. the cost.

 

Yep, that sums things up nicely.

 

I'll be polite and call this statement hogwash. Time for you to call 'your' engineer again.

 

This is like saying that by taking Vitamin C pills daily, your life will be extended. Maybe this is true and maybe it is not. I don't see how this can be proved unless a double-blind test is taken.

In the case of Hondas, we would need two sample groups of Honda hybrid owners who have logged a similar mix of model year age and odometer readings. Each group has to believe that the grid charging has been performed, but in fact the procedure is done on only one group. Then see what the failure rate of the two groups is over time.

 

I'm not too worried about the cars being affected by placebo*, but I whole-heartedly agree with your sentiment. The benefit is simply unproven in terms of likelihood, duration and magnitude. And personally, I prefer to invest the money in a new battery.

Too bad Seilerts is not around to throw in his two cents.

*We can ignore owner subjectivity by requiring battery death as an end-point.

 

Not to put words into Jeff's mouth, but he may have meant that 95% of batteries with compromised life (either throwing the IMA light and/or doing constant recals) have shown improvement, not that otherwise good batteries have lasted longer than if not grid charged. In the Gen1 Insight community, the general consensus is that a grid charger can help extend a compromised battery's useful life by a year or more.

 

This is my view as well. Of course, it took a lot of practice and a lot of help from others who went before me.

I'd add that using a whole pack charger with logging of ( charge volts, amps, pack temps and discharge slope and time ) with a calibrated discharger, can significantly increase successful rebalancing hybrid packs. As long as the pack is not soak charged and or deep discharged continually.

Also, a new pack is typically the best option for those who can afford it or have it done for them under warranty.

 

I'm not in the hogwash business . It's actually above 95%, I was rounding down. For every 100 chargers we sell, we have about 2-4 people who report back to us after the first charge balance session that their battery was no better off than before they used our product.

If it helps, you can look at our eBay feedback for the last 12 months. It's a small sample of our customer base, but it might help those who question my integrity. Over the last year, we have 81 customers who have left feedback about the chargers, and only three have reported that the charger did not help their car. Here are some of my favorite comments from our customers:

Grid charger is the cats nice person. No more IMA lights. Excelnt comm after deliver, A+

Works! I'm composing a letter to seller to let him know how satisfied I am!

Fast ship, 30 min response to ?s. Works great no CEL, no recals in 4 weeks

Excellent instructions, rapid response to tech support, a MUST for hybrids! A+++

Super fast shipping. Top notch customer service and communication. Thanks

Here is the link if you'd like to read for yourself:
eBay Feedback Profile for hybridautomotive

Sure, eBay alone is not >95%, but that is not all of our customer base either . . .

 

The benefit received from charging and rebalancing really depends on the pack itself. We have had customers with badly failed packs that have only brought them back for a few months before the battery could not go any longer. Most commonly we have customers who starting using the charger after the first battery imbalance trouble code/check engine light. Many of those customers have added 12-18 months or more to the battery life and are still going. If the red triangle is due to hard hard failure such and internal short or high IR the charger cannot help, those modules must be replaced. As I said above, 2-3% of our customers report that the battery is just a dead after using our product as it was before they used it.

We also have customers who started using them while the battery is still healthy - as preventative maintenance. While the amount of life they will add to their hybrid battery is hardest to quantify, it is still well known (outside this forum) that the sooner one starts using a grid charger the more benefit it will deliver to extend overall battery life and vehicle performance.

 

Hybrids are complicated machines. There are usually other issues with the car when it sets pack codes. And if those codes are reset and or ignored
the success rate after installing a remanufactured pack drop significantly.
There are lots of stories on the net. You have to go with the ones that make the most sense to you per your specific set of circumstances.

 

You are thinking of my Electrical Engineer (the one who spends his days working on cars for some guy named Musk). He is currently helping get the third generation Prius charger systems released, hopefully before Christmas

I was actually working with my Mechanical Engineer today. We are working on a new fixture to improve the Prius fan control board enclosure holes. We currently hand drill each one from a sheet metal template. He is building a special fixture from hardened tool steel to more precisely locate and align the fan inlet and exhaust ports. It's a minor item really, but we want our to continue to improve the product whenever possible. Here is a peek at the CAD layout of the fan enclosure, which is the first step to building the tool: