Source of Li-ion batteries, HV question

The vehicle only has one traction battery, so it's probably easiest to think of the charge in terms of a fuel tank. When you run out of EV range, it's like a traditional fuel tank switching over to Reserve. You'll also notice that the charge indicator switches from a solid bar to one with horizontal stripes.

If you have enough of a drop in elevation, you can easily regenerate enough power to obtain additional EV range. I've done this many times, as I live in a very hilly area, but it won't indicate anything less than 1 mile EV range by regeneration, so there's definitely a bit of a threshold for those who live in flat areas.

 

Panasonic provides both the Li-ion and NiMH batteries.

 

have you read through the faq? very informative.

 

Apparently the quality of rechargeable batteries varies considerably. One of the most common lithium cells is the 18650, which is used in a wide variety of applications, including laptops and the Tesla. A version of this battery with built-in protection for use in flashlights and other devices was originally designated the 19670, but most vendors call it the 18650.

On YouTube you can see how much variability there is in capacity of these cells when they are subjected to load-testing. One tested cell was actually packed with an unknown inert powder, with a small lithium cell in the middle. This was designed to dupe the casual user, who doesn't have a good idea of how long such a cell should last between rechargings.

 

Panasonic provide Lithium battery modules to Toyota and Ford hybrids (and plugins).

They have modules tuned for high power (for hybrids) and high energy (tuned for plugin hybrids).



Panasonic Group to Supply Lithium-ion Batteries for Toyota Prius Plug-in Hybrid | Panasonic News Portal
Panasonic to Supply Lithium-ion Battery Cells for Ford Motor Company's Hybrid and Plug-in Hybrid Vehicles | Panasonic News Portal

 

To answer the rest of your questions.

State of charge ~85% to ~22% is used for EV. ~22% (8 bars) to 19% (1 bar) is maintained in HV mode.

 

Those modules look like they would be real easy to replace if one went bad. Yet we all we hear about is the high cost of replacing the entire stack. Is there some reason why internal diagnostics could not point to a bad module, and that module be replaced.

 

There are some YouTube videos which explain how to identify bad cells, replace them, and how to equalize the charge on the replaced cells.

I think it's actually a good idea to use salvaged cells, because they are a better match to work with older remaining cells. New cells would be harder to equalize in an older battery, and vice-versa. If the battery is quite old and out of warranty, patching it up with replacement cells might just be prolonging the inevitable need to replace the whole battery.

If I had one bad cell, I might try bridging the gap with a blank. The overall voltage won't be affected; it will still charge the battery up to the required level.

Mind you, with the 8-year warranty on hybrid components in this car, I probably won't be doing any such work before I trade it off.

 

The only disturbing thing about the battery warranty is that Toyota won't cover gradual inability to hold a charge unless it's a true "failure." It would be interesting what CARB would say if, during the warranty, EV range goes down to 50% of original.

I do hope all our obsessing over babying the batteries is for nothing.

 

Those of us in California Air Resource Board (CARB) states have a 10yr/150k warranty on the hybrid system, including the battery. (Yes, I understand that Canada has its own rules.)

 

I've heard various things, but The Prius "babies" the battery by keeping the charge range between 40 and 80% for the sake of longevity. This should keep it in fairly good condition for a number of years. Even if it were degraded to 50% capacity, the hybrid function would still work fine, but the EV range would decrease. In the case of the plug-in it would go from 10-12 miles to 5-6 miles. Not a big deal in my opinion.

 

I'm not sure if there's any government-mandated warranty period on hybrids here or not.

 

It would be a big deal to me. And since it would not be anywhere close to the emission saver that got it CARB approval, I do question whether Toyota's disclaimer would hold much legal weight if someone pursued a warranty repair.

A Brave New World we are in. I do agree that the HSD's battery management, which has been perfected over 18 years, keeps batteries in their "happy" states of charge. Nonetheless, that explicit disclaimer still gives me dyspepsia.

 

Don't know about North American laws, but over here, there is mandatory consumer protection that goods have to be of 'satisfactory quality', which the courts have interpreted as lasting a reasonable time for the product concerned. Given the 8 year battery warranty, I don't think an argument that it is still working but at 50% efficiency would wash. 20% after eight years, maybe.

I think I posted this before, but Toyota UK said in an FAQ that the battery should last the life of the car Toyota Prius Plug-in: your questions answered « Toyota UK news, reviews, video and pictures
Again, I don't think the courts would let them get away with saing it has lasted but only at 50%. So presumably Toyota are happy the car that we are all driving (more or less) will live up to these claims.

 

Have you seen that Toyota UK have decided to reduce the warranty for their hybrids and PHEVs from 8 years to just 5? Effective for new sales from April this year! Why?

Toyota Warranty | Toyota UK

You can either pay extra to have the optional Hybrid Health Check completed which will cover you upto 10 years inclusive. This is automatically included if you service your car at Totota. I also wonder if it applies to just hybrids or plug-ins as well?

 

I believe the California-mandated 10-year warranty was applied across the board in North America to discourage shopping across state-lines, however as distances from California increase, the warranties decrease. Here in Canada, it's 8 years. That's my guess.

 

I believe the California-mandated 10-year warranty was applied across the board in North America.

No! Just in carb states, other wise it is 8 years.
I might be wrong, but do not think so.