When I moved house about five years ago, I stupidly left my motor mower
in the shed!! Stupid Me! So, over the last five years, I've been getting
a 'Jim's Gardening' guy in to mow and clean up the garden every three or
four months, at $75-$100 a go!

A while ago, I learned that one of my sisters had brought a Ryobi
Battery Mower, so this week, I've borrowed it and mowed my lawns. It did
a good enough job for me. The Battery takes about two hours to recharge.

Back in a previous life, I was an Electronic Technician, and, at the
time of Ni-Cad batteries being introduced, the recharge story was that
Ni-Cads should be fully discharged occasionally, otherwise they
developed a 'memory' such that if they were regularly used/discharged to
a particular amount, whenever they got to that level, they would stop
working.

They then had to be 'manually' flattened by continually being turned on
..... and turned on .... and turned on ... Until they were 'flat', so
that they could then take a full charge and be 'right-as-rain'!!

With that in mind, and remembering that it supposedly only takes two
hours to fully recharge the Mower Battery, would it be better, after
use, to leave the battery 'Flat' or 'flatish' or should the battery be
fully recharged ready for use .... even though that use might be a month
or two hence??

TIA
--
Daniel

On 12/2/22 10:13 pm, Daniel65 wrote:
> When I moved house about five years ago, I stupidly left my motor mower
> in the shed!! Stupid Me! So, over the last five years, I've been getting
> a 'Jim's Gardening' guy in to mow and clean up the garden every three or
> four months, at $75-$100 a go!
>
> A while ago, I learned that one of my sisters had brought a Ryobi
> Battery Mower, so this week, I've borrowed it and mowed my lawns. It did
> a good enough job for me. The Battery takes about two hours to recharge.
>
> Back in a previous life, I was an Electronic Technician, and, at the
> time of Ni-Cad batteries being introduced, the recharge story was that
> Ni-Cads should be fully discharged occasionally, otherwise they
> developed a 'memory' such that if they were regularly used/discharged to
> a particular amount, whenever they got to that level, they would stop
> working.
>
> They then had to be 'manually' flattened by continually being turned on
> .... and turned on .... and turned on ... Until they were 'flat', so
> that they could then take a full charge and be 'right-as-rain'!!
>
> With that in mind, and remembering that it supposedly only takes two
> hours to fully recharge the Mower Battery, would it be better, after
> use, to leave the battery 'Flat' or 'flatish' or should the battery be
> fully recharged ready for use .... even though that use might be a month
> or two hence??

Forget everything you know about Nicads. Almost all modern battery tools
use Lithium batteries. I believe the Ryobi ones (like many others)
have smart charge circuits in each battery, that takes care of
balancing, etc.

Lithium prefers not to be flattened fully, and the optimum charge for
long-term storage is 60-70%, not empty or full. The self-discharge rate
is basially zero compared to anything previous.

On Sat, 12 Feb 2022 22:13:09 +1100, Daniel65
<daniel47@eternal-september.org> wrote:

> When I moved house about five years ago, I stupidly left my motor mower
> in the shed!! Stupid Me! So, over the last five years, I've been getting
> a 'Jim's Gardening' guy in to mow and clean up the garden every three or
> four months, at $75-$100 a go!
>
> A while ago, I learned that one of my sisters had brought a Ryobi
> Battery Mower, so this week, I've borrowed it and mowed my lawns. It did
> a good enough job for me. The Battery takes about two hours to recharge.
>
> Back in a previous life, I was an Electronic Technician, and, at the
> time of Ni-Cad batteries being introduced, the recharge story was that
> Ni-Cads should be fully discharged occasionally, otherwise they
> developed a 'memory' such that if they were regularly used/discharged to
> a particular amount, whenever they got to that level, they would stop
> working.
>
> They then had to be 'manually' flattened by continually being turned on
> .... and turned on .... and turned on ... Until they were 'flat', so
> that they could then take a full charge and be 'right-as-rain'!!
>
> With that in mind, and remembering that it supposedly only takes two
> hours to fully recharge the Mower Battery, would it be better, after
> use, to leave the battery 'Flat' or 'flatish' or should the battery be
> fully recharged ready for use .... even though that use might be a month
> or two hence??

It doesnt matter with current Lithium Ion batterys.

Daniel65 is an IDIOT wrote:
========================
>
>
> Back in a previous life, I was an Electronic Technician,

** And I was Napoleon.

> at the
> time of Ni-Cad batteries being introduced,

** 1960's ?

> the recharge story was

** Mostly myth.
> Ni-Cads should be fully discharged occasionally, otherwise they
> developed a 'memory' such that if they were regularly used/discharged to
> a particular amount, whenever they got to that level, they would stop
> working.

** Not true.
>
> With that in mind, and remembering that it supposedly only takes two
> hours to fully recharge the Mower Battery, would it be better, after
> use, to leave the battery 'Flat' or 'flatish' or should the battery be
> fully recharged ready for use .... even though that use might be a month
> or two hence??

** There are no NiCds in your mower.

....... Phil

Clifford Heath wrote on 12/02/2022 11:00 pm:
> On 12/2/22 10:13 pm, Daniel65 wrote:
>> When I moved house about five years ago, I stupidly left my motor
>> mower in the shed!! Stupid Me! So, over the last five years, I've been
>> getting a 'Jim's Gardening' guy in to mow and clean up the garden
>> every three or four months, at $75-$100 a go!
>>
>> A while ago, I learned that one of my sisters had brought a Ryobi
>> Battery Mower, so this week, I've borrowed it and mowed my lawns. It
>> did a good enough job for me. The Battery takes about two hours to
>> recharge.
>>
>> Back in a previous life, I was an Electronic Technician, and, at the
>> time of Ni-Cad batteries being introduced, the recharge story was that
>> Ni-Cads should be fully discharged occasionally, otherwise they
>> developed a 'memory' such that if they were regularly used/discharged
>> to a particular amount, whenever they got to that level, they would
>> stop working.
>>
>> They then had to be 'manually' flattened by continually being turned
>> on .... and turned on .... and turned on ... Until they were 'flat',
>> so that they could then take a full charge and be 'right-as-rain'!!
>>
>> With that in mind, and remembering that it supposedly only takes two
>> hours to fully recharge the Mower Battery, would it be better, after
>> use, to leave the battery 'Flat' or 'flatish' or should the battery be
>> fully recharged ready for use .... even though that use might be a
>> month or two hence??
>
> Forget everything you know about Nicads. Almost all modern battery tools
>  use Lithium batteries. I believe the Ryobi ones (like many others)
> have smart charge circuits in each battery, that takes care of
> balancing, etc.
>
> Lithium prefers not to be flattened fully, and the optimum charge for
> long-term storage is 60-70%, not empty or full. The self-discharge rate
> is basially zero compared to anything previous.

Ah!! So much the same as Ni-Cad, then. Thanks
--
Daniel

On 13/02/2022 21:27, Daniel65 wrote:
> Clifford Heath wrote on 12/02/2022 11:00 pm:
>> On 12/2/22 10:13 pm, Daniel65 wrote:
>>> When I moved house about five years ago, I stupidly left my motor
>>> mower in the shed!! Stupid Me! So, over the last five years, I've
>>> been getting a 'Jim's Gardening' guy in to mow and clean up the
>>> garden every three or four months, at $75-$100 a go!
>>>
>>> A while ago, I learned that one of my sisters had brought a Ryobi
>>> Battery Mower, so this week, I've borrowed it and mowed my lawns. It
>>> did a good enough job for me. The Battery takes about two hours to
>>> recharge.
>>>
>>> Back in a previous life, I was an Electronic Technician, and, at the
>>> time of Ni-Cad batteries being introduced, the recharge story was
>>> that Ni-Cads should be fully discharged occasionally, otherwise they
>>> developed a 'memory' such that if they were regularly used/discharged
>>> to a particular amount, whenever they got to that level, they would
>>> stop working.
>>>
>>> They then had to be 'manually' flattened by continually being turned
>>> on .... and turned on .... and turned on ... Until they were 'flat',
>>> so that they could then take a full charge and be 'right-as-rain'!!
>>>
>>> With that in mind, and remembering that it supposedly only takes two
>>> hours to fully recharge the Mower Battery, would it be better, after
>>> use, to leave the battery 'Flat' or 'flatish' or should the battery
>>> be fully recharged ready for use .... even though that use might be a
>>> month or two hence??
>>
>> Forget everything you know about Nicads. Almost all modern battery tools
>>   use Lithium batteries. I believe the Ryobi ones (like many others)
>> have smart charge circuits in each battery, that takes care of
>> balancing, etc.
>>
>> Lithium prefers not to be flattened fully, and the optimum charge for
>> long-term storage is 60-70%, not empty or full. The self-discharge
>> rate is basially zero compared to anything previous.
>
> Ah!! So much the same as Ni-Cad, then. Thanks

No, if you treat them like Ni-Cads you will destroy them, even the new
smart ones with charge/discharge limiting circuitry built in to them.

Charge it up, use it, and if it gets low charge it again, other wise
leave it on the shelf until you need to use it.

If you know you are going to use it a lot tomorrow, charge it up today
if it's not full.

Cheers,
Gary B-)

Daniel65 wrote:
=============
>
> > Forget everything you know about Nicads. Almost all modern battery tools
> > use Lithium batteries. I believe the Ryobi ones (like many others)
> > have smart charge circuits in each battery, that takes care of
> > balancing, etc.
> >
> > Lithium prefers not to be flattened fully, and the optimum charge for
> > long-term storage is 60-70%, not empty or full. The self-discharge rate
> > is basially zero compared to anything previous.
>
> Ah!! So much the same as Ni-Cad, then. Thanks
>

** A bind man once met an elephant.
He grabbed the animal by the tail and exclaimed:

" Ahhh .... elephant just like snake "

........ Phil

On 13/2/22 9:27 pm, Daniel65 wrote:
> Clifford Heath wrote on 12/02/2022 11:00 pm:
>> On 12/2/22 10:13 pm, Daniel65 wrote:
>>> When I moved house about five years ago, I stupidly left my motor
>>> mower in the shed!! Stupid Me! So, over the last five years, I've
>>> been getting a 'Jim's Gardening' guy in to mow and clean up the
>>> garden every three or four months, at $75-$100 a go!
>>>
>>> A while ago, I learned that one of my sisters had brought a Ryobi
>>> Battery Mower, so this week, I've borrowed it and mowed my lawns. It
>>> did a good enough job for me. The Battery takes about two hours to
>>> recharge.
>>>
>>> Back in a previous life, I was an Electronic Technician, and, at the
>>> time of Ni-Cad batteries being introduced, the recharge story was
>>> that Ni-Cads should be fully discharged occasionally, otherwise they
>>> developed a 'memory' such that if they were regularly used/discharged
>>> to a particular amount, whenever they got to that level, they would
>>> stop working.
>>>
>>> They then had to be 'manually' flattened by continually being turned
>>> on .... and turned on .... and turned on ... Until they were 'flat',
>>> so that they could then take a full charge and be 'right-as-rain'!!
>>>
>>> With that in mind, and remembering that it supposedly only takes two
>>> hours to fully recharge the Mower Battery, would it be better, after
>>> use, to leave the battery 'Flat' or 'flatish' or should the battery
>>> be fully recharged ready for use .... even though that use might be a
>>> month or two hence??
>>
>> Forget everything you know about Nicads. Almost all modern battery tools
>>   use Lithium batteries. I believe the Ryobi ones (like many others)
>> have smart charge circuits in each battery, that takes care of
>> balancing, etc.
>>
>> Lithium prefers not to be flattened fully, and the optimum charge for
>> long-term storage is 60-70%, not empty or full. The self-discharge
>> rate is basially zero compared to anything previous.
>
> Ah!! So much the same as Ni-Cad, then. Thanks

No. One area NiCd differs is that it can withstand continuous low-level
overcharging. NiMH and Li batteries die from that kind of treatment.

CH

Clifford Heath wrote:
=================
>
A blind man said:
=================
>
> > Ah!! So much the same as Ni-Cad, then.
>
> No. One area NiCd differs is that it can withstand continuous low-level
> overcharging. NiMH and Li batteries die from that kind of treatment.
>

** However, trickle charging is OK.

Most NiMH cells suffer from high self discharge rates.
Only 1 month and they are almost useless.
( Eneloop ones are far better)

Trickle charging at about the 30 to 50 hour rate is OK.

....... Phil

Gary R. Schmidt wrote on 13/2/22 11:00 pm:
> On 13/02/2022 21:27, Daniel65 wrote:
>> Clifford Heath wrote on 12/02/2022 11:00 pm:
>>> On 12/2/22 10:13 pm, Daniel65 wrote:
>>>> When I moved house about five years ago, I stupidly left my motor
>>>> mower in the shed!! Stupid Me! So, over the last five years, I've
>>>> been getting a 'Jim's Gardening' guy in to mow and clean up the
>>>> garden every three or four months, at $75-$100 a go!
>>>>
>>>> A while ago, I learned that one of my sisters had brought a Ryobi
>>>> Battery Mower, so this week, I've borrowed it and mowed my lawns. It
>>>> did a good enough job for me. The Battery takes about two hours to
>>>> recharge.
>>>>
>>>> Back in a previous life, I was an Electronic Technician, and, at the
>>>> time of Ni-Cad batteries being introduced, the recharge story was
>>>> that Ni-Cads should be fully discharged occasionally, otherwise they
>>>> developed a 'memory' such that if they were regularly
>>>> used/discharged to a particular amount, whenever they got to that
>>>> level, they would stop working.
>>>>
>>>> They then had to be 'manually' flattened by continually being turned
>>>> on .... and turned on .... and turned on ... Until they were 'flat',
>>>> so that they could then take a full charge and be 'right-as-rain'!!
>>>>
>>>> With that in mind, and remembering that it supposedly only takes two
>>>> hours to fully recharge the Mower Battery, would it be better, after
>>>> use, to leave the battery 'Flat' or 'flatish' or should the battery
>>>> be fully recharged ready for use .... even though that use might be
>>>> a month or two hence??
>>>
>>> Forget everything you know about Nicads. Almost all modern battery tools
>>>   use Lithium batteries. I believe the Ryobi ones (like many others)
>>> have smart charge circuits in each battery, that takes care of
>>> balancing, etc.
>>>
>>> Lithium prefers not to be flattened fully, and the optimum charge for
>>> long-term storage is 60-70%, not empty or full. The self-discharge
>>> rate is basially zero compared to anything previous.
>>
>> Ah!! So much the same as Ni-Cad, then. Thanks
>
> No, if you treat them like Ni-Cads you will destroy them, even the new
> smart ones with charge/discharge limiting circuitry built in to them.
>
> Charge it up, use it, and if it gets low charge it again, other wise
> leave it on the shelf until you need to use it.

Sorry, should have mentioned it is Lithium-ion.

If I were to "leave it on the shelf" for a month or so (How often do
people mow their lawns?? Often in Spring, not so often rest of yer??),
would the Lithium-ion battery still be holding a charge??
>
> If you know you are going to use it a lot tomorrow, charge it up today
> if it's not full.

Yes, that's always an option as it only takes a couple of hours on the
charger to be fully charged.

I was just wondering .... for the long-term good on the Battery.

Thanks to all for their responses. ;-)
--
Daniel

On 14/02/2022 09:37, Clifford Heath wrote:
> On 13/2/22 9:27 pm, Daniel65 wrote:
>> Clifford Heath wrote on 12/02/2022 11:00 pm:
>>> On 12/2/22 10:13 pm, Daniel65 wrote:
>>>> When I moved house about five years ago, I stupidly left my motor
>>>> mower in the shed!! Stupid Me! So, over the last five years, I've
>>>> been getting a 'Jim's Gardening' guy in to mow and clean up the
>>>> garden every three or four months, at $75-$100 a go!
>>>>
>>>> A while ago, I learned that one of my sisters had brought a Ryobi
>>>> Battery Mower, so this week, I've borrowed it and mowed my lawns. It
>>>> did a good enough job for me. The Battery takes about two hours to
>>>> recharge.
>>>>
>>>> Back in a previous life, I was an Electronic Technician, and, at the
>>>> time of Ni-Cad batteries being introduced, the recharge story was
>>>> that Ni-Cads should be fully discharged occasionally, otherwise they
>>>> developed a 'memory' such that if they were regularly
>>>> used/discharged to a particular amount, whenever they got to that
>>>> level, they would stop working.
>>>>
>>>> They then had to be 'manually' flattened by continually being turned
>>>> on .... and turned on .... and turned on ... Until they were 'flat',
>>>> so that they could then take a full charge and be 'right-as-rain'!!
>>>>
>>>> With that in mind, and remembering that it supposedly only takes two
>>>> hours to fully recharge the Mower Battery, would it be better, after
>>>> use, to leave the battery 'Flat' or 'flatish' or should the battery
>>>> be fully recharged ready for use .... even though that use might be
>>>> a month or two hence??
>>>
>>> Forget everything you know about Nicads. Almost all modern battery tools
>>>   use Lithium batteries. I believe the Ryobi ones (like many others)
>>> have smart charge circuits in each battery, that takes care of
>>> balancing, etc.
>>>
>>> Lithium prefers not to be flattened fully, and the optimum charge for
>>> long-term storage is 60-70%, not empty or full. The self-discharge
>>> rate is basially zero compared to anything previous.
>>
>> Ah!! So much the same as Ni-Cad, then. Thanks
>
> No. One area NiCd differs is that it can withstand continuous low-level
> overcharging. NiMH and Li batteries die from that kind of treatment.

Also, if a NiCd ever gets totally flat, you can just charge it and use
it, sometimes even many years later (if it doesn't develop shorted
cells, or if you succeed in blasting away the shorts with a high current
pulse, which I have sometimes). If a lithium battery ever gets totally
flat (or even below about 2.3V per cell I think), the electronics in the
pack may prevent you from ever charging it again, (perhaps for safety
reasons). If storing a lithium battery for a long time, it is best to
charge it to maybe 60% so that it won't get too flat by self-discharge,
and then store it in a cool place. Charging it to 100% before storing it
is not a good idea as that causes faster degradation.

This is interesting, though I can't vouch for its correctness:
https://www.youtube.com/watch?v=sRwoYJyjZNo

On 14/02/2022 19:37, Daniel65 wrote:
[SNIP]
>
> Sorry, should have mentioned it is Lithium-ion.
>
Yes, we realise that.

> If I were to "leave it on the shelf" for a month or so (How often do
> people mow their lawns?? Often in Spring, not so often rest of yer??),
> would the Lithium-ion battery still be holding a charge??
>>

My jump-starter is LiFePO4 - Lithium Iron Phosphate (supposedly the
latest and the greatest :-) ) - it says check every six months and /if/
it's dropped below 70% top it up.

The Bunnings Ozito PXC batteries say they lose 5-10% a month, but they
don't appear to specify a trigger point for re-charging. I haven't
noticed any of mine going low enough to worry about, I just charge them
after use and toss them back in the bag when they've cooled down, they
get used once a month or so.

> Yes, that's always an option as it only takes a couple of hours on the
> charger to be fully charged.
>
> I was just wondering .... for the long-term good on the Battery.
>
Don't leave them on charge, don't let them get and stay low, store them
where the temperature is fairly stable, that's about it.

Cheers,
Gary B-)

Daniel65 <daniel47@eternal-september.org> wrote
> Gary R. Schmidt wrote on 13/2/22 11:00 pm:
>> On 13/02/2022 21:27, Daniel65 wrote:
>>> Clifford Heath wrote on 12/02/2022 11:00 pm:
>>>> On 12/2/22 10:13 pm, Daniel65 wrote:

>>>>> When I moved house about five years ago, I stupidly left my motor
>>>>> mower in the shed!! Stupid Me! So, over the last five years, I've
>>>>> been getting a 'Jim's Gardening' guy in to mow and clean up the
>>>>> garden every three or four months, at $75-$100 a go!
>>>>>
>>>>> A while ago, I learned that one of my sisters had brought a Ryobi
>>>>> Battery Mower, so this week, I've borrowed it and mowed my lawns. It
>>>>> did a good enough job for me. The Battery takes about two hours to
>>>>> recharge.
>>>>>
>>>>> Back in a previous life, I was an Electronic Technician, and, at the
>>>>> time of Ni-Cad batteries being introduced, the recharge story was
>>>>> that Ni-Cads should be fully discharged occasionally, otherwise they
>>>>> developed a 'memory' such that if they were regularly
>>>>> used/discharged to a particular amount, whenever they got to that
>>>>> level, they would stop working.
>>>>>
>>>>> They then had to be 'manually' flattened by continually being turned
>>>>> on .... and turned on .... and turned on ... Until they were 'flat',
>>>>> so that they could then take a full charge and be 'right-as-rain'!!
>>>>>
>>>>> With that in mind, and remembering that it supposedly only takes two
>>>>> hours to fully recharge the Mower Battery, would it be better, after
>>>>> use, to leave the battery 'Flat' or 'flatish' or should the battery
>>>>> be fully recharged ready for use .... even though that use might be
>>>>> a month or two hence??
>>>>
>>>> Forget everything you know about Nicads. Almost all modern battery
>>>> tools
>>>> use Lithium batteries. I believe the Ryobi ones (like many others)
>>>> have smart charge circuits in each battery, that takes care of
>>>> balancing, etc.
>>>>
>>>> Lithium prefers not to be flattened fully, and the optimum charge for
>>>> long-term storage is 60-70%, not empty or full. The self-discharge
>>>> rate is basially zero compared to anything previous.
>>>
>>> Ah!! So much the same as Ni-Cad, then. Thanks
>> No, if you treat them like Ni-Cads you will destroy them, even the new
>> smart ones with charge/discharge limiting circuitry built in to them.
>> Charge it up, use it, and if it gets low charge it again, other wise
>> leave it on the shelf until you need to use it.
>
> Sorry, should have mentioned it is Lithium-ion.
>
> If I were to "leave it on the shelf" for a month or so (How often do
> people mow their lawns?? Often in Spring, not so often rest of yer??),

Right thru spring, summer and autumn. Not much in the winter.

> would the Lithium-ion battery still be holding a charge??

Varys with the tech. No problem charging it before use with mowing tho.

>> If you know you are going to use it a lot tomorrow, charge it up today
>> if it's not full.
>
> Yes, that's always an option as it only takes a couple of hours on the
> charger to be fully charged.
>
> I was just wondering .... for the long-term good on the Battery.

Gary R. Schmidt wrote on 15/2/22 1:10 am:
> On 14/02/2022 19:37, Daniel65 wrote:
> [SNIP]
>>
>> Sorry, should have mentioned it is Lithium-ion.
>>
> Yes, we realise that.
>
>> If I were to "leave it on the shelf" for a month or so (How often do
>> people mow their lawns?? Often in Spring, not so often rest of yer??),
>> would the Lithium-ion battery still be holding a charge??
>>>
>
> My jump-starter is LiFePO4 - Lithium Iron Phosphate (supposedly the
> latest and the greatest :-) ) - it says check every six months and /if/
> it's dropped below 70% top it up.
>
> The Bunnings Ozito PXC batteries say they lose 5-10% a month, but they
> don't appear to specify a trigger point for re-charging.  I haven't
> noticed any of mine going low enough to worry about, I just charge them
> after use and toss them back in the bag when they've cooled down, they
> get used once a month or so.
>
>> Yes, that's always an option as it only takes a couple of hours on the
>> charger to be fully charged.
>>
>> I was just wondering .... for the long-term good on the Battery.
>>
> Don't leave them on charge, don't let them get and stay low, store them
> where the temperature is fairly stable, that's about it.
>
>     Cheers,
>         Gary    B-)

Thank you. ;-)
--
Daniel

On 12/02/2022 7:13 pm, Daniel65 wrote:
> When I moved house about five years ago, I stupidly left my motor mower
> in the shed!! Stupid Me! So, over the last five years, I've been getting
> a 'Jim's Gardening' guy in to mow and clean up the garden every three or
> four months, at $75-$100 a go!
>
> A while ago, I learned that one of my sisters had brought a Ryobi
> Battery Mower, so this week, I've borrowed it and mowed my lawns. It did
> a good enough job for me. The Battery takes about two hours to recharge.
>
> Back in a previous life, I was an Electronic Technician, and, at the
> time of Ni-Cad batteries being introduced, the recharge story was that
> Ni-Cads should be fully discharged occasionally, otherwise they
> developed a 'memory' such that if they were regularly used/discharged to
> a particular amount, whenever they got to that level, they would stop
> working.
>
> They then had to be 'manually' flattened by continually being turned on
> .... and turned on .... and turned on ... Until they were 'flat', so
> that they could then take a full charge and be 'right-as-rain'!!
>
> With that in mind, and remembering that it supposedly only takes two
> hours to fully recharge the Mower Battery, would it be better, after
> use, to leave the battery 'Flat' or 'flatish' or should the battery be
> fully recharged ready for use .... even though that use might be a month
> or two hence??
>
> TIA

Charge and leave them that way they will be ready for use when you need
them. Forget NiCads, not relevant here.