Building battery from MAKITA Konion PACK

Batteries, Chargers, and Battery Management Systems.
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Doctorbass   100 GW

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Re: Building battery from MAKITA Konion PACK

Post by Doctorbass » Apr 28 2017 1:08pm

One more important detail:

VTC5 is LiMn ( Lithium Manganese)
VTC5A is NMC ( Nickel Manganese Cobalt)

Even with the VTC5 with awsome power and energy performance that beat alot of common cells, Their NMC version, the VTC5A are capable of more power and for twice more time before overheat.. however they cost more and are not used in the Makita.

Even with a drag race pack of only 2p and made of the VTC4 or VTC5A, it would be possible to get peak amp of 160A for 10sec!!

Doc
CURRENT PROJECT: 2WD duo MXUS/Max-E ebike 32kW
http://endless-sphere.com/forums/viewto ... =3&t=65764
-Fastest speed record 117 km/h on flat
-Fastest 1/4 mile@ 114km/h on flat and 16.316 sec
-Succeded to haul a 19200 pounds schoolbus!
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Mongoosehttp://www.evalbum.com/1947
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markz   100 GW

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Re: Building battery from MAKITA Konion PACK

Post by markz » May 03 2017 1:28pm

Thanks Doctorbass for the package :)

Is there a good lower volt limit to maintain healthy cells for longevity?
I tend to charge back up after using to lvc to a middle of the road voltage.
I ride everyday, if I store its to nominal, or leave it for a day or 2 or 3.

My pack is 18Ah and bulk charges at 16A in cc/cv (Meanwell HRP's) at 0.89C to 4.15V/cell.
My cont. LVC is set to 2.80V/cell but its actually works more like a 3.00V/cell cutoff
There is a setting to use 3.20V/cell.

I have the 3Ah Makita's 18650-V cells which are LiMn (I believe)

Overall I am very pleased, here is what mine look like with the case off. I am going with a 36Vnom setup so everything gives me 60Ah or 2160Wh which I tend to use up 22Wh/km, depending on conditions of course. I have never seen a 18650 before, only 26650's.
makita1.jpg
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makita2.jpg
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Re: Building battery from MAKITA Konion PACK

Post by Doctorbass » May 03 2017 2:16pm

markz wrote:Thanks Doctorbass for the package :)

Is there a good lower volt limit to maintain healthy cells for longevity?
I tend to charge back up after using to lvc to a middle of the road voltage.
I ride everyday, if I store its to nominal, or leave it for a day or 2 or 3.

My pack is 18Ah and bulk charges at 16A in cc/cv (Meanwell HRP's) at 0.89C to 4.15V/cell.
My cont. LVC is set to 2.80V/cell but its actually works more like a 3.00V/cell cutoff
There is a setting to use 3.20V/cell.

I have the 3Ah Makita's 18650-V cells which are LiMn (I believe)

Overall I am very pleased, here is what mine look like with the case off. I am going with a 36Vnom setup so everything gives me 60Ah or 2160Wh which I tend to use up 22Wh/km, depending on conditions of course. I have never seen a 18650 before, only 26650's.
makita1.jpg
makita2.jpg
Hi Mark,

for longevity it is recommanded to avoid complete discharge down to LVC.. and laso to chage at lower C rate when cell are at LVC until they reach about 5% SOC.

For exemple, the Volt battery pack withc use NMC cells are keeping pack with in 20-80% SOC so they never ho below 20% and never go above 80% ( 4.05v/cell)

3.4V lvc for the V cells is a good lvc number by experience. This will keep cells from going out of balance ( that usually happen at end of discharge)
You must know that rebalancing cells state is not good for cell longevity as it keep majority of clles at the top 100% SOC for extended period until the lower cell reatch them.

So Avoid using cells too close to 3.0v and it shoudl work fine for long... 3.4V is good lvc and you dont loose too much usable capacity per cycle.

Doc
CURRENT PROJECT: 2WD duo MXUS/Max-E ebike 32kW
http://endless-sphere.com/forums/viewto ... =3&t=65764
-Fastest speed record 117 km/h on flat
-Fastest 1/4 mile@ 114km/h on flat and 16.316 sec
-Succeded to haul a 19200 pounds schoolbus!
113kmh Gianthttp://www.evalbum.com/3406
Mongoosehttp://www.evalbum.com/1947
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I speak FRENCH and english

markz   100 GW

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Re: Building battery from MAKITA Konion PACK

Post by markz » May 06 2017 1:56pm

These 3Ah (2P) packs have the black holder keeping the cells tight. Not much movement trying to pry/push one side out with my fingers.

The packs DB did are 1.5Ah (1P)

I am still pondering and would like to halve my work load keeping them in 1S2P, when I charge them up and let them sit for a week before I move ahead.

If I cant get apart - Is it wise to leave them as is 5S2P charge up, sit 1 week, then connect up to whatever size I want?
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Doctorbass   100 GW

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Re: Building battery from MAKITA Konion PACK

Post by Doctorbass » May 06 2017 7:01pm

markz wrote:These 3Ah (2P) packs have the black holder keeping the cells tight. Not much movement trying to pry/push one side out with my fingers.

The packs DB did are 1.5Ah (1P)

I am still pondering and would like to halve my work load keeping them in 1S2P, when I charge them up and let them sit for a week before I move ahead.

If I cant get apart - Is it wise to leave them as is 5S2P charge up, sit 1 week, then connect up to whatever size I want?

You can use a dremel to cut the nickel. I have suggested that solutin many times. it work great but require good handling of that tool.

Doc
CURRENT PROJECT: 2WD duo MXUS/Max-E ebike 32kW
http://endless-sphere.com/forums/viewto ... =3&t=65764
-Fastest speed record 117 km/h on flat
-Fastest 1/4 mile@ 114km/h on flat and 16.316 sec
-Succeded to haul a 19200 pounds schoolbus!
113kmh Gianthttp://www.evalbum.com/3406
Mongoosehttp://www.evalbum.com/1947
YOUTUBE---https://m.youtube.com/user/Doctorbasss
http://twitter.com/DocbassMelancon
I speak FRENCH and english

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Re: Building battery from MAKITA Konion PACK

Post by markz » May 08 2017 5:56pm

The first one I opened was the oddball, must be an old old one. All the rest seem to be like the ones in the video.

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Re: Building battery from MAKITA Konion PACK

Post by steveo » May 09 2017 10:17am

Hey Everyone,

I have thought about using 18650 holders to build my battery, however i would prefer to per say "glue" the cells together to build my 2 battery modules due to space limitation. I'm thinking 16 to 20p and each module at 10s. The parallel groups will be in horizontal orientation, the pack will be wired for ease or capability of max current flow provided evenly for the cells.

Whatever i decide to glue them with, i want something that is strong like using hot glue, however if something goes wrong in the pack, i want to have the option to disassemble and rebuild, and i feel hot glue is simply to strong and to hard to disassemble if required, or maybe i'm wrong here. Any other ideas i could use? like silicone perhaps?

love to hear suggestions


-Steveo
Repair Thread
http://endless-sphere.com/forums/viewto ... =3&t=27170
Hub Monster bike ~ 24s7p A123 15.4ah/18kv Six Phase Motor/Dual Max-E Adapttos/32kw~42.91Hp/Est 140LBS
X6 Kmx Trike ~ 24s4p 20ah/X6 MHM 602/Infinion EB324 IRFB 4110/20Kw~26.82Hp/Est 120LBS ~SOLD~
Lightening rods bike ~ 18s2p 10ah/1500w Inrunner/Infinion EB312 IRFB4110/2KW~2.68hp/Est 60LBS
EV Outboard ~ 12s8p 40ah/5KW GM Inrunner/Infinion EB324 IRFB 4110/18Hp Evinrude Drive/Est 100lbs
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markz   100 GW

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Re: Building battery from MAKITA Konion PACK

Post by markz » May 09 2017 2:30pm

Hot glue is not that strong, and if the battery cans ever heat up it could loosen the grip the hot glue has.
When I was looking at Aucklands Grainger website, they seemed to have a wide variety of hot glue sticks available.
I used generic no name glue sticks from Crap-O-Rama.

A suggestion would be to use 18650 sleeves and perhaps a tube of glue used for construction from Home Depot.

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Re: Building battery from MAKITA Konion PACK

Post by litespeed » May 09 2017 10:35pm

On my next build I'm going to just hot glue the parallel cells together. Then use the 25 mm wide nickel like I have in the past to connect the multiple parallel groups in series. This way the pack would open up accordion style for easy access to the cells should one need to be replaced some day.

Replacing one now is not a good time at all.

Tom
I'm married so you know I'm no stranger to pain!

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Re: Building battery from MAKITA Konion PACK

Post by steveo » May 10 2017 9:54pm

Thanks for the suggestions!

I think i will be going with some 18650 sleeves or shrink wrap over the cells.. then using hot glue to hold everything. I doubt heat will be a issue with a 18p or 20p group of cells.. they will only ever see 20amp peak on a 20p group.. I don't want to use pl premium.. its awesome stuff.. but impossible to pull apart anything. we shall see!

-Steveo
Repair Thread
http://endless-sphere.com/forums/viewto ... =3&t=27170
Hub Monster bike ~ 24s7p A123 15.4ah/18kv Six Phase Motor/Dual Max-E Adapttos/32kw~42.91Hp/Est 140LBS
X6 Kmx Trike ~ 24s4p 20ah/X6 MHM 602/Infinion EB324 IRFB 4110/20Kw~26.82Hp/Est 120LBS ~SOLD~
Lightening rods bike ~ 18s2p 10ah/1500w Inrunner/Infinion EB312 IRFB4110/2KW~2.68hp/Est 60LBS
EV Outboard ~ 12s8p 40ah/5KW GM Inrunner/Infinion EB324 IRFB 4110/18Hp Evinrude Drive/Est 100lbs
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Matador   10 kW

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Re: Building battery from MAKITA Konion PACK

Post by Matador » Jun 25 2017 2:42pm

Well I finally finished my EXTENSIVE caracterisation of the VTC4 cells I bought from DoctorBass (Makita BL1840 10 cells packs).

I thought posting the results would help people decide by themselves if these cells are suited for their needs and what to expect.
So this post is to give you the results, which quite frankly, are difficult to beat considering the great low price.

So I bought 29 Makita BL1840 Pack from DoctorBass last February 2017.
That is 290 cells. From these, 4 cells were dead (voltage close to 0). The 286 cells lefts were as good as new (see my Excel file below). They were all retrieved at normal operating voltage (Lowest 3.46V ; Highest 4.02 V)... Most in the 3.70V region.

I have actually noticed that the BL1840 packs
(Packs of "18"-650 cells ; "4.0" Ah per pack) can have either one of two kinds of Sony Cells...
I retrieved 218 sony VTC4 cells (22 Makita packs) and 68 sony VT4 cells (7 Makita packs).
The VTC4 and VT4 cells seems different, as VTC4 have on average slightly lower DC internal resistance than the VT4 cells (all cells compared at same voltage of 3.65V/50% SOC). Capacity seems almost identical though.
So VTC4 and VT4 are completely different animals with different specs, although I can't seem to find a specsheet for the VT4 cells on the internet.

With all my data, I did a statistics summary :
BL1840 cells Statisticds.jpg
BL1840 cells Statisticds.jpg (72.8 KiB) Viewed 1409 times
As you can see I measured DCIR of 22 mOhms for the VTC4 versus 28 mOhms for the VT4.
For the capacity, average was 2190 mAh for VTC4 versus 2119 mAh for VT4.
I did buy them almost 6 months ago, but as of today, these cells are average 2.4 years old for VTC4 and 3.1 years old for VT4 (exact date to the exact day was obtained from date code on each cell).

So now, here are the detailed results. To extensively caracterise each one of the single cells, I did 4 things :

1) Determine the "Salvaged voltage" (anything below 2.5 Volts upon recovery and I would discard these cells).... Note that as soon as I got the packs, I dismantled them to remove the BMS (Battery Murderer Systems that drain down your cells beyond recoverable with long storage times).

2) Measure "Single cell Capacity" (I used 3 x Foxnovo 4S Digital Chargers to measure each cells, 12 cells at a time.... Discharge mAh determined on highest setting (mAh@0.5A discharge/cell.... while charging is done at 1.0A/cell).

3) Measure "DC Internal Resistance" (DCIR) . For that, I used my Imax B6 Mini, which now has the option to determine internal resistance of cells !!! Surprizingly accurate for a non-4-lead measuring device... I found the measures in the 20 mOhm range is around ±5 mOhm margin of error (temperature drifts from time to time).... There are some value drift with temperatures, but repeating measures at different periodes of times help you find the real value (ex : 26 mOhm, 21mOhm, 20 mOhm, 19 mOhm, 22 mOhm... Okay, 26 mOhm is the alien value to eliminate here) ... To compare, I did regression analysis with another method of determination of DCIR (V= -r I + EMF) and getting the slope of graph to get DCIR value, while testing cells at different known loads (Ammeter connected) and reading voltage drop simultanously (voltmeter connected too) for different loads (different 50W resistors used for loads). For exemple, with this method, I measured DCIR of 19.9 mOhm by regression analysis, while for the exact same cell the Imax B6 gives me a value of 22 mOhm. Accurate enough for my needs!!! No cells were of bad DCIR (except the 4 dead ones, reading in the 70 milliohm range when charged before experimenting, then tossed away). I compared with result I got with using different resistors and tracing graphs to get the slope (which gives the DCIR):viewtopic.php?f=14&t=87173&start=25#p1276187

4) I measured "Ability to Maintain Same Voltage Over Time" (see Excel file below). They did not move significantly over a the course of 3 week test at full 100% SOC : 4.2V. Then, for optimal storage , I discharged all cells to 50% SOC (I did a giant parallel solderless 130P1S and then another 166P1S parallel pack and used a load to discharge the whole thing while monitoring voltage with CellLog 8M to 3.650 V target voltage for storage.
For cells 1-130, Final discharge voltage was 3.651 V. For cells 131-290, Final discharge voltage was 3.657 V.
Three months later, the cells have not moved of a single millivolt. None of them moved (I rechecked every cell's voltage individually, every months). See my Excel file below for data.

So I must say, these cells, I consider of A+++ quality. Just be aware that a few Makita BL1840 pack (about 1 pack out of 4 packs) actually contain VT4 cell in place of VTC4 cells. And these cells I don't know well, but are around 6 milliohms more and about 70 mAh less than the VTC4 on average.

Still, amazing deal if you want my opinion. All in all, I'm glad I bought these cells, as the lower price compared to new cells allowed me to buy valuable tools with that money (Imax-B6 Mini, B168 active balance charger, HP DPS-1200 power supply, Ming He BSW900 boost converter, 3 Foxnovo Digital 4S chargers, A dremel (OMG the best tool ever.... All these tool I will be able to use in the future if I need to). Did a little mod to the foxnovo 4S charger : viewtopic.php?f=14&t=86556&p=1266049&hi ... o#p1266049

Also, all these cells comes already spotwelded to tabs... And we're talking COPPER TABS here !! (nickel-plated solid copper core), so yes... big amps ! Don't believe me it's copper ? Check pics here : viewtopic.php?f=14&t=84680&p=1275118&hi ... a#p1274883

Here is the Data I compiled on every single cell I got (extensive caracterisation) :
3box%20VTC4.jpg
Thanks again DoctorBass.... I'll be a client again next year when I come back from my training in NYC. Also, when I come back, I intend to build a "real" ebike.... I mean the "10 kW and up" Kind of eBike with massive front fork supension, DOT tires, Hydraulic breaks, Crazy tork arms (maybe the NYX frame), and a suitable battery (Sony cells of course), so I'll need your wisdom...

Cheers,

Matador
Last edited by Matador on Aug 22 2018 8:47pm, edited 12 times in total.

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Doctorbass   100 GW

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Re: Building battery from MAKITA Konion PACK

Post by Doctorbass » Jun 25 2017 4:50pm

Big thanks Matador for the extensive and excellent work.

The level of detail you use to work on these is outstanding and an exemple to follow.

I'm very glad that you also apprecaite tehse just like hundreds of buyers. But on your side you all tested the proof that these are very great cells!

Again, i'm very impressed :wink:

I wish this exemple will be also used by many members.

Doc
CURRENT PROJECT: 2WD duo MXUS/Max-E ebike 32kW
http://endless-sphere.com/forums/viewto ... =3&t=65764
-Fastest speed record 117 km/h on flat
-Fastest 1/4 mile@ 114km/h on flat and 16.316 sec
-Succeded to haul a 19200 pounds schoolbus!
113kmh Gianthttp://www.evalbum.com/3406
Mongoosehttp://www.evalbum.com/1947
YOUTUBE---https://m.youtube.com/user/Doctorbasss
http://twitter.com/DocbassMelancon
I speak FRENCH and english

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Re: Building battery from MAKITA Konion PACK

Post by want to build » Jun 23 2018 7:20pm

hi
Once the packs are opened an you want to build a battery,
if you have a lii 500, is it the nor test that is to be use or the charge mode?
tx

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Re: Building battery from MAKITA Konion PACK

Post by litespeed » Jun 24 2018 9:39am

want to build wrote:
Jun 23 2018 7:20pm
hi
Once the packs are opened an you want to build a battery,
if you have a lii 500, is it the nor test that is to be use or the charge mode?
tx
I’m not sure what your asking?

Tom
I'm married so you know I'm no stranger to pain!

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Re: Building battery from MAKITA Konion PACK

Post by want to build » Jun 24 2018 4:41pm

hi the lii500 offers 3 options, 1 charge 2 fast test 3 nor test.
the nor test is said to do this : charge discharge to 2.8v and then recharge.
i want to dobble check if it is the nor test that i need to use or is better to just pick option 1 which is just charge.

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Re: Building battery from MAKITA Konion PACK

Post by want to build » Aug 14 2018 8:58pm

hi everyone,

I almost have charged all my cell in nor mode with lee charger

How to see wich are the bad cell.

1right after openning, they were all above 3 volt so i kept them all.
2i charged them all to 4.19 volts
3i waited 2 weeks

now from what i have understood, i have to ? check the voltage ? or what test do i need to do?
What is the acceptable voltage at wich i put the cell to garbage bad apples (recycle) and keep the cell to build my battery

thx

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Re: Building battery from MAKITA Konion PACK

Post by litespeed » Aug 15 2018 4:14pm

Put them in groups......all cells that kept voltage at full charge 4.2 volts in one group. All cells that fell to 4.0 to 4.1v in another and so on.

Hopefully you end up with enough 4.2 cells to build your pack.

Tom
I'm married so you know I'm no stranger to pain!

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Re: Building battery from MAKITA Konion PACK

Post by litespeed » Aug 15 2018 4:15pm

Anything that dropped below 4 volts I’d pitch.

Tom
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Re: Building battery from MAKITA Konion PACK

Post by want to build » Aug 16 2018 6:38am

Hi

when you suggest to regroup the batteries into like 4 to 4.05 , 4.05 to 4.10 , 4.10 to 4.15, 4.15 to 4.19,

do you mean that all 4.00 to 4.05 should be put in a same paralle groupe or that the shoud be in spreaded in equal number in each paralelle groups ?

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Re: Building battery from MAKITA Konion PACK

Post by litespeed » Aug 16 2018 6:46am

I would make all “P” groups the same voltage which would be most important. Then you want your “S” groups to be the same as well or as close as you can. If not the higher resistance “P” groups (lower voltage) will drag the rest of the pack down and if you use those in the middle of the pack could over heat causing yet another issue.

So how many really good cells (4.10 or above?) did you get out?

Tom
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Re: Building battery from MAKITA Konion PACK

Post by want to build » Aug 16 2018 7:15am

I still have to wait a bit for some to let them macerate to see if they are god or bad apples.

would a 2week wait after charge be sufficient to separate the good from the bads?

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Re: Building battery from MAKITA Konion PACK

Post by litespeed » Aug 16 2018 8:29am

2 weeks is what I did.....some might have been a bit longer.

Tom
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Re: Building battery from MAKITA Konion PACK

Post by Matador » Aug 16 2018 8:52pm

Did a few months... See my results from my previous post (in the excel sheet).

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Re: Building battery from MAKITA Konion PACK

Post by want to build » Aug 16 2018 10:41pm

ok
just after charging them with lii 500 all of them showed 4.17 418 4.19 or 4.20

after 3 weeks i have 4 cells at 4.15
14 at 4.16
54 at 4.17
26 at 4.18
7 at 4.19

total 105on paper
110 cell over 4.15 total concretely
so i guess i have 5 cell using a number already used(concentration mistake) it happens :)

now are they all suitable to put in a battery usable ? here is the sheet i have to see how much they lowered.
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8.gif

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Re: Building battery from MAKITA Konion PACK

Post by want to build » Aug 16 2018 10:54pm

now i have a very important question:
i plan to buy a lunacycle blue charger advanced that is said to offer posibility to charge at 1 amp 2, 3, 4, or 5 amps for fast charge and also allow to charge 80 , 90 100 pourcent.

here is the thing. i will have 2 types of usage, one is in city(only for 2 or 3 hills max 15 min total.
and for bike travels (several miles per day)

for travel i will put the bike in my tent so there is no worry for stealing.

But in city, Since it is not convenient to carry a battery in my back pack, i would leave the battery in the bike hoping no one will steal it

i though of separating my battery in 2 sections 2p 14 s for city . this means that if it got stolen i wont hurt me as much as if the whole battery is stolen. is 2p14 s relatively safe with a bms to use or i'm completely dreaming? i would charge it at 1 amp . what is the minimum of cells in parallel . Could one use a 1p 13 s to ride (total of 2.1amp x 48v= 100amph) divided by 20 it would mean 5 miles possibility..

for longer ride, i would connect the rest of the cells for one big battery.

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