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T i m T i m is offline
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Default Mini review: Aldi battery mower

On 07 Jun 2021 18:14:31 +0100 (BST), Theo

T i m wrote:
On Mon, 07 Jun 2021 15:12:11 +0100, John Bryan
The energy monitor inside the car normally has one bar left.

So it knows there is 40% left but inhibits you using it any further?

The bars are fiction - they're an indication of the battery status but not a
direct measure of it.

I'm surprised. I know (from personal experience) it's difficult to
accurately indicate the current SOC of a battery but you would have
thought that with all the engineering that Toyota obviously put into
even the first Prius, it would have a fairly accurate battery gauge?

You can read out the SoC with OBD if you want the
actual numbers.

That makes even less sense then if 'better' information is available
but not used?

I think 'nearly full' at the top of the blue bars which is
where it prefers to keep it is something like 66% of SoC and the extra two
green bars come up to at about 80%.


If you do regen you can get those green bars to fill up, but it won't do it
from the engine out of choice.


Ah, 'additional', so am I right in thinking it would typically include
electrical / regenerative braking *and then* mechanical braking under
all circumstances? I believe Theo suggested that the mechanical
braking can come in quickly if you aren't gentle on the brake but I
wasn't sure if it *always* applied both or if there were instances
where you just had mechanical only (other than when it was 100%
charged etc)?

I believe it's mech only below 7mph on Gen2.

Yes, I believe you said.

If you emergency stop I don't
know what it does with regen, but it stops like any other car.

I guessed it would but I was (only) wondering if the braking role was
a direct function of the pedal position / hydraulic pressure in that
it went though the 'electric' then 'mechanical' braking no matter how
fast / hard you pressed the pedal or if the electric was bypassed (as
opposed to not having time to come in) if you did a rapid stop. Not
because of the outcome (as you say, it should / would stop like any
other car), but the process behind the scenes.

Way to think of it is that it's basically normal mechanical braking but with
regen creaming off energy when it can. If you brake gently you hear the
regen, if you drive it heavily the friction will take over.

Understood, where the 'taking over' is simply mechanical braking
effect out-performing the electric braking effect (both are likely
still running in parallel).

It takes quite a bit to fill this one bar and I have only seen it happen
once in the two years I have driven my Prius generation 3.

Nice long down hills where you had to apply some level of braking the
whole time?

Not sure about the Gen3 but it's easy on a Gen2 - motorway offslip with
nobody behind you so you can brake through it gently down from 70mph.

Gotcha. So not that long / difficult then?

Or on
hills, I hear they have them in other parts of the country.

Apparently.[1] ;-)

Actually, whilst watching (typically) taxi drivers dropping people off
when out walking the dog when it's quiet at night and being fascinated
by the 'silence' as these (typically Prius's) waft about, I have
suggested to the Mrs we see how much it would cost to hire one for a
day, when we have somewhere 'urban' to go?

I am familiar with pure EV's as I have had one for over 30 years, but
it's very basic (std mechanical brakes and no regen), not a hybrid and
it's those that interest me from these technical / usage POV.

The older ones are easier to work out what's going on.

I imagined they might be. Not that 'evolution' can not also include
'simplification' but it rarely seems to.

The newer ones have
it blended more smoothly so it's harder to tell what it's doing.

Do you feel they have done that with advanced software or are you
aware of significant advances in the drivetrain / rolling gear?

In general
you just drive it like a normal car, there's nothing extra to do.

Funnily, that also applies to my old EV, just that there is no engine
noise when you turn it 'On'. ;-)

There's a display that shows what's happening with energy transfer which is
useful when you first get it and want to understand what's going on:
('Classic' is a Gen1, 'Iconic' a G2)

Interesting ta. I might make a replica one with an Arduino to put in
the Meriva. ;-)

Some of the newer ones have this as a prettier display but much less
readable when driving:

Why do they do that. ;-(

It looks 'bling' but as you say, probably doesn't convey the
information as clearly as the 'old way'.

It was a bit like that with my older Garmin GPS's and the newer one.
The newer one is obviously more targeted at 'Consumers' but there was
a load more information you could optionally select / display (that
probably wouldn't be of interest to 'most people').

I think other Toyota hybrids have a similar screen, possibly more hidden in
the entertainment system. Almost all new Toyota autos are hybrids these
days (apart from the diesels and the sports cars), so probably wouldn't be
too difficult to hire one.

I'll see what's about (I'd want to have at least a day driving it
'normally' myself, rather than blagging a test drive etc).

Cheers, T i m

[1] Something you don't necessarily notice till you are on a cycle or
driving a pure EV. ;-)