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Makita Battery cell 20700

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All the different solutions have their pros and cons. Hitachi’s will limit them into only having 2 banks of cells. Just as Flexvolt can only work with 3. So I see Hitachi hitting a performance ceiling more quickly than either X2 or Flexvolt. Well, unless they also start doing some “X2” variant a la Makita. Which they can, I guess. Both Dewalt and Ryobi actually have their own rebrandings of X2. Hitachi doing X2 would then be able to say they have 72V. So actually that may not be that bad.

 

Makita by appearances seems to like to keep their line appearing uncluttered, whether or not that’s beneficial or not. Maybe it’s to maximize compatibility or simplify the system intuitively for customers, but I don’t anticipate we’ll ever see them release a 3Ah compact until they decide their just done with the current 2-bank 3Ah, for example.

 

I mention this because I get the impression they don’t want to do both 3-bank 18650 batteries and 2-bank 20/21700s at the same time. I can see advantages to either direction, and wouldn’t personally care if they released both. But a lot of buyers would probably get confused when one format invariably doesn’t work with this or that tool they already have. The tabs that prevent users from using compact batteries on most Makita tools already get grumbles from people.

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If Makita uses bigger cells, then X2 tools are going to be seriously heavy and huge. Flexvolt are big with 15 cells, but Makita are possibly going to have 20 x 21700 cells on a single tool! 
 
I think Hitachi/Hikoki with Multivolt have a better approach. It's like a middle ground between Flexvolt and X2. A single 18650 Multivolt battery will do 36V and be exactly the same size as one of their original 6ah 18V batteries. To improve runtime (and likely power), they also have a bigger 21700 cell 8ah/4ah version that is 1440Wh. It's bigger, but not as big as Flexvolt or 2 x Makita batteries.
 
We haven't seen any reviews yet, but in theory Multivolt is looking like a winner. I kind of wish it was Makita that came up with the idea instead (or be the first ones to copy Flexvolt if you prefer I put it that way).
No reviews on MultiVolt because it isn't released yet. Official release is next Tuesday.

Also, Hitachi had to pay up some for using voltage switching as DeWalt holds the patent.

There has also been a MultiVolt X2 battery dust extractor spotted in Japan.
.
And Makita is so damn secretive.

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6 minutes ago, The.Handyman said:

it isn't released yet. Official release is next Tuesday

 

That might be for the US only. Online stores in Australia are listing it as 'In Stock', but I guess it may not be actually true. One store does have a YouTube channel and have 2 videos up (the 36V rotary hammer and 36V impact wrench). I placed an order for the small battery yesterday so it should be here in 2 days time if it's actually available. I'll try to post a mini review when it arrives.

 

9 minutes ago, The.Handyman said:

Hitachi had to pay up some for using voltage switching as DeWalt holds the patent.

 

I wondered about that. It was a great idea from Dewalt.

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I wondered about that. It was a great idea from Dewalt.
Yes, sorry, I am referring to the North American release. I can't keep up with worldwide releases.

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6 minutes ago, The.Handyman said:

I can't keep up with worldwide releases.

 

Same here. It was hard enough to find our local release date. All we got was "October".

 

I'm looking forward to the US release. I'll consider that the "Official" release date (US have a huge market and the most YouTube channels/reviewers). It's a damn shame about the "Metabo HPT" name though. 

 

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Hitachis multivolt advantage is plain and simple, the ac adapter. It makes things like a sawzall and skilsaw much more useful. 

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9 hours ago, D W said:

If Makita uses bigger cells, then X2 tools are going to be seriously heavy and huge. Flexvolt are big with 15 cells, but Makita are possibly going to have 20 x 21700 cells on a single tool! 😨

 

I think Hitachi/Hikoki with Multivolt have a better approach. It's like a middle ground between Flexvolt and X2. A single 18650 Multivolt battery will do 36V and be exactly the same size as one of their original 6ah 18V batteries. To improve runtime (and likely power), they also have a bigger 21700 cell 8ah/4ah version that is 1440Wh. It's bigger, but not as big as Flexvolt or 2 x Makita batteries.

 

We haven't seen any reviews yet, but in theory Multivolt is looking like a winner. I kind of wish it was Makita that came up with the idea instead (or be the first ones to copy Flexvolt if you prefer I put it that way).

 

That's exactly why Makita are reluctant to push bigger batteries based on current technology and why the 9ah rumours are unfounded.

 

Every one I've spoken to (of course I can't verify it but it makes a lot of sense) who works with or for Makita suggest it's not of great importance to them. I've said this earlier on in the thread.

 

Who wants to lug heavy tools around all day just because they're Cordless? 

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Yes but, would 2 21700 cell 4 amp batteries weigh more and out perform 2 5 amp 18700 cell batteries?  The question is can Makita make longer run time batteries without the weight and bulk of the Dewalt and Milwaukee batteries. 

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7 hours ago, glass said:

Yes but, would 2 21700 cell 4 amp batteries weigh more and out perform 2 5 amp 18700 cell batteries?  The question is can Makita make longer run time batteries without the weight and bulk of the Dewalt and Milwaukee batteries. 

 

Possible but longevity would be greatly reduced.

 

https://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

 

Any potential increse in runtime is minimised by the cost and reduced life span of the battery.

 

Factor in the higher temprature generated after drawing greater current from fewer cells and you have a further decrease of life span.

 

While the salesman would like to offer it as an option to customers, Makita has already (and is still trying to distance itself from) been through battery issues early on when they entered the li-ion market. It would be foolish to leave anything to chance and a battery that doesn't last as long as the user would like would only help to perpetuate a bad reputation.

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Within reason, larger cells will be able to belt out more current per-cell without negatively affecting longevity. That’s another part of the attraction of larger cells.

 

Makita’s X2 tools aren’t really where they need bigger capacity batteries (yet) though. From where I sit it’s more about the larger-consumption 18 volt tools. A pair of Makita’s 6Ah batteries in X2 is still running perfectly even with Milwaukee’s and Dewalt’s newest 12Ah batteries. But those 12Ah batteries can be used on any of their tools, while Makita’s non-X2 are limited to 6Ah. Not really an issue for most of them, in fact they look (and are) stupid on things like impact drivers, compact drills, and other small tools. Plenty of other tools though extra Ah is a good idea, as is a design that can output more current than 2 banks of 18650 cells.

 

Personally I think Makita should aim to retain an apparent edge by aiming between the grooves, where their X2 tools will have a decided advantage in Ah while not giving up too much on higher-drain non-X2 tools. 8-9Ah units should be a priority somewhere in the not-too-distant future.

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One brand should go out on a limb with this idea:

 

Removable and sealed 3 or 5 cell cartridges or pods that you load into slide packs like we know them today (like loading individual batteries into a flashlight for example, but cartridges into slide packs which would essentially just be containers for the cartridges). The slide packs would come in a few sizes such as 1, 2, 4, and 8 cartridge packs. You could then "build" the sized battery you need. A 3 cell per cartridge approach would allow "12V", "24V", "48V", and a 5 cell per cartridge approach would allow "18V", "36V", "72V" etc. Both have advantages.

 

So a tool would be rated by the minimum number of cartridges or pods that are needed for it to run (with voltage not really being the thing that is referred to).

 

With a 3 cell per cartridge approach:

 

A "12V max" tool would be rated 1+ (1 cartridge minimum). If you use a slide pack that holds 2 cartridges, then the tool would increase the run-time by using them in parallel. Hypothetically it could also use a 4 or 8 cartridge pack for extra long run-time.

 

A "24V max" tool would be rated 2+ (2 cartridges minimum) and use the 2 cartridges in series. If you use a 4 cartridge pack, then it would use two pairs of in series cartridges in parallel.

 

A "48V max" would be rated 4+...and so on.

 

 

This approach could allow a 12V rotary tool to exist on the same platform as a 48V mower.

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8 hours ago, ToolBane said:

Within reason, larger cells will be able to belt out more current per-cell without negatively affecting longevity. Thats another part of the attraction of larger cells.

 

That's simply not true. Lithium is lithium, packing more of it into a cell doesn't make it perform any better or worse. It's longevity would be better compared to a smaller celled battery but that's not to say it would perform any better based on what's there. More cells offer better longevity at lower voltage.

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50 minutes ago, SchenzhenSpecial said:

 

That's simply not true. Lithium is lithium, packing more of it into a cell doesn't make it perform any better or worse. It's longevity would be better compared to a smaller celled battery but that's not to say it would perform any better based on what's there. More cells offer better longevity at lower voltage.

Don't really think you are correct ?

 

The 21700 cells have a higher continuous amp output then 18650 cells. That's what's toolsbane is saying.

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13 minutes ago, SchenzhenSpecial said:

That's simply not true.

 

It’s entirely true, by the same means that two cells in parallel will output twice the current as a single cell, which is why power tools so often have better performance output with 2-bank batteries versus 1-bank “compact” batteries.

 

All other things being equal a cell that is larger will have lower internal resistance since the current is flowing across a larger cross-sectional surface area, and since there’s also more mass, the battery will dissipate more energy lost as heat before increasing temperature by any given amount.

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30 minutes ago, kornomaniac said:

Don't really think you are correct ?

 

The 21700 cells have a higher continuous amp output then 18650 cells. That's what's toolsbane is saying.

 

Then that's what he should have said. Not what he actually said, which implied lithium would perform differently because there's more of it. The performance of the battery isn't the same as the performance of the heavy metal the cell is made of.

 

28 minutes ago, ToolBane said:

It’s entirely true, by the same means that two cells in parallel will output twice the current as a single cell, which is why power tools so often have better performance output with 2-bank batteries versus 1-bank “compact” batteries.

 

 

You're talking about performance over increased capacity. On what you're saying 100 cells would perform better than 1 cell. Yes. That's true, that's not what you said, or at least not how it was was worded.

 

9 hours ago, ToolBane said:

Within reason, larger cells will be able to belt out more current per-cell without negatively affecting longevity. That’s another part of the attraction of larger cells.

 

This isn't true.

 

A larger capacity cell will be able to belt out more current per-cell no different to a 2gallon bottle holding more water than a 1gallon bottle.

 

That is not to say the lithium within the cell will deteriorate at a slower rate.

 

I've linked you to a study which looks at the rate of deterioration compared to amount of recharge cycles, already.

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Your story isn't correct either.

 

Charge cycles isn't the only thing that deteriorates battery cells.

 

Heat is the most important factor. Thzts also on battery University  to quote your source. 21700 cells can output more current for less heat buildup.

 

Less heat = longer lifespan.

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48 minutes ago, kornomaniac said:

Your story isn't correct either.

 

Charge cycles isn't the only thing that deteriorates battery cells.

 

Heat is the most important factor. Thzts also on battery University  to quote your source. 21700 cells can output more current for less heat buildup.

 

Less heat = longer lifespan.

 

 

I've already said this. 

 

17 hours ago, SchenzhenSpecial said:

 

Factor in the higher temprature generated after drawing greater current from fewer cells and you have a further decrease of life span.

 

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6 hours ago, SchenzhenSpecial said:

Not what he actually said, which implied lithium would perform differently because there's more of it. The performance of the battery isn't the same as the performance of the heavy metal the cell is made of.

 

Not what I said at all. The lithium’s behavior not changing (although it CAN be changed, but for the purposes of this discussion we’re assuming it isn’t changing to a significant degree) has nothing to do with why there will be a higher current output available if the cell is bigger. The electrical resistance of any given component in the circuit path is dependent on a number of factors, but one of them is cross-sectional area of the resisting material.

 

I don’t know if you’ve ever seen the water-through-tube analogy used to help describe how lower resistance allows more current flow, but that’s one concept that will be operating here. You make the tube bigger, more water will flow under any given amount of pressure. The same way simply adding a second tube will flow more water. What most directly governs that? Well you’ve increased the cross-sectional area of the “conductor”. The water hasn’t changed. The pipe material hasn’t changed. The resistance drops because the cross-sectional area of the conductor has been increased. It operates the same whether we’re putting two cells in parallel or just making a bigger cell. The material property of the lithium or anything else hasn’t changed in either case. I’m not going to go dig through your “Battery University” website for you to find where they’ll likely explain it but if they go into the topic at any college-level detail at all (hell even just slightly beyond freshman highschool physics) they’ll eventually cover this. That is if they are reasonably scientifically responsible. Just because they call themselves “Battery University” doesn’t guarantee they actually have University-level information on-hand.

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43 minutes ago, ToolBane said:

Not what I said at all. 

 

18 hours ago, ToolBane said:

Within reason, larger cells will be able to belt out more current per-cell without negatively affecting longevity. That’s another part of the attraction of larger cells. 

 

Your words.

 

51 minutes ago, ToolBane said:

nothing to do with why there will be a higher current output available if the cell is bigger. The electrical resistance of any given component in the circuit path is dependent on a number of factors, but one of them is cross-sectional area of the resisting material. 

 

I'm well aware of this.

 

8 hours ago, SchenzhenSpecial said:

A larger capacity cell will be able to belt out more current per-cell no different to a 2gallon bottle holding more water than a 1gallon bottle.

 

At this point I'm struggling to see what it is you're arguing about.

 

If you have 8 cells putting out 2amps at 20v, they're going to perform better for longer than 4 cells putting out 2 amps at 20v. Why are you going in circles talking about cell capacity?

 

23 hours ago, SchenzhenSpecial said:

Any potential increse in runtime is minimised by the cost and reduced life span of the battery.

 

A new Bosch 'slim' 4ah is currently selling in the UK for around £70. For the same money I can have the 18650 lined

6ah. Is the 4ah slim going to outperfom the 6ah? On current, yes - should the tool need it. Run time? Probably not. Cost for its lifespan, very unlikely.

 

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7 hours ago, SchenzhenSpecial said:

Your words.

 

Correct, and nowhere do my words imply that the properties of lithium change based on cell size.

 

8 hours ago, SchenzhenSpecial said:

I'm well aware of this.

 

Except you continue to not properly apply the pertinent concepts, sooo...?

 

8 hours ago, SchenzhenSpecial said:

At this point I'm struggling to see what it is you're arguing about.

 

Why are you going in circles talking about cell capacity?

 

I think it’s plain as day obvious when I say larger cells and larger cross-sectional areas I am referring to physical sizes and not Ah capacities.

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