Building battery from MAKITA Konion PACK

Batteries, Chargers, and Battery Management Systems.
want to build   10 W

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Re: Building battery from MAKITA Konion PACK

Post by want to build » Aug 19 2018 4:56pm

want to build wrote:
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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markz   100 GW

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Re: Building battery from MAKITA Konion PACK

Post by markz » Aug 19 2018 5:40pm

Better to have charged them to 3.70 volts and let them sit because its not good to have them full voltage for a long time like that.

markz   100 GW

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Re: Building battery from MAKITA Konion PACK

Post by markz » Aug 19 2018 5:45pm

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..
1P is no good because the discharge amperage is only 8-10A (I am guessing as to what the specs say, but do confirm bc I cant remember) so when you do that, and you get 20-30A you hurt your babies.
2P means you can do 16-20A
3P means you can do 24-30A
4P is 32-40A.

Now you go with a 30A 18650 then its 1P = 30A, 2P 60A, 3P 90A, 4P 120A discharge.

You could have a small 1P or 2P and 13S pack which would net you 48V(nominal) and 30A or 60A but with them Makita's its only 10A and 20A.

want to build   10 W

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Re: Building battery from MAKITA Konion PACK

Post by want to build » Dec 15 2018 7:45pm

HI i purchased opus bt c 3100 and got all my cell out of the makita packs . It did keep the 2,5v and more. Now , before choosing which cells to put in parallele with which , it seems i need to know their capacity.

I have a need for clarity about what mode i need to use and what current because it seems to allow 200 500 and 1000 ma both for charge and dischage.

there is a refresh mode ?? that i read on a blog i dont know if it is a reliable synthesis see bottom

some places i read just charge the cells . Somewhere else charge it discharge it and charge it so i feel confuse and need you knowledge advice and a bit of help on which is the best setting . (i want to build a quality long lasting battery.. :)

thanks

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The unit has 5 selectable modes including Charge, Discharge, Test, Quick test, and Refresh.

Charge Mode: The rechargeable battery is charged up to its maximum capacity. Accumulated charging capacity is displayed at mAH display mode.
The charger will charge 4 cells at once charging each at 1 amp. But if you are charging only 2 batteries you should put them in the outer slots (slots 1 and 4) to increase the charging rate to 2 amps a piece. This is especially good for charging 2 26650’s at the same time

Discharge Mode: Discharge mode is used to reduce memory effect, The rechargeable battery is discharged to a preset battery voltage (0.9v for Ni-Cd & Ni-Mh, 2.8v for Li-ion batteries). Once discharge is finished, total accumulated discharging capacity is displayed at mAH display mode.

Refresh Mode: The rechargeable battery is charged and discharged repeatedly to optimize to its maximum capacity. Old rechargeable batteries or rechargeable batteries that have not been used for a long period of time can be restored to their rated capacity

want to build   10 W

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Re: Building battery from MAKITA Konion PACK

Post by want to build » Dec 20 2018 10:33pm

hi ,
anyone has used this charger ? Me and my questions would like to be sure i m using the right modes and current
here is a owner manual on line. (english is not my first language by the way)

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Matador   10 kW

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Re: Building battery from MAKITA Konion PACK

Post by Matador » Dec 20 2018 10:47pm

Dude, just use 1000 mA (C/2)... It's much faster to test each cells. 500 mA (C/4) will take twice as long and 200 mA (C/10) will take 5 times as long.
In any case, the capacity you'll get on your eBike will be slightly different from that you test, whatever the setting, because you'll very likely drain these cells above 2 to 3C anyways... But these cells are 10C capable (they will heat up however at that rate...) ao no worries.

On think to keep in mind though, for sake of comparing what is comparable, whatever rate of charge/discharge you use to test capacity, use the same rate between all cells, so you compare apples with apples.

Matador

want to build   10 W

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Re: Building battery from MAKITA Konion PACK

Post by want to build » Dec 20 2018 11:33pm

Yes i understand that i have to test all cell again.

I m new to 18650 so i dont know concretly witch mode do i have to set my opus3100 to in order to know it s capacity.
maybe that is not what i have to do but that is what i have understood that needs to be done to match equal parallel total capacity group.

so do i need to charge and discharge?

The unit has 5 selectable modes including Charge, Discharge, Test, Quick test, and Refresh.
Concretely , one i have inserted 4 cells in the charger,and plug the charger, what mode do i put it in?

I read the charger in refresh mode goes down to 2,8 v wich might be detrimental? Do i even need to use the discharge refresh mode(it runs 6 times)

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Matador   10 kW

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Re: Building battery from MAKITA Konion PACK

Post by Matador » Dec 21 2018 6:09pm

Both. Charge, then discharge. What you want is discharge capacity. Charge capacity is not reliable because all the cells from different packs are not necessarly in the same state of charge (some cells may be 52% charges, some 23%, some 97%). So some will need less charge time to become full. But once full, discharge to minimum voltage will give you capacity.

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Matador   10 kW

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Re: Building battery from MAKITA Konion PACK

Post by Matador » Dec 21 2018 6:15pm

2.8V is not dramatic, so as long as they do not ever reach below 2.5V, you're good.

Learn about your VTC4 cells. CHECK THE DATASHEET which has all the specifications:
Specification_US18650VTC4.pdf
(875.07 KiB) Downloaded 11 times
On that datasheet, you will see that the manufacturer (Sony), specify it's okay to discharge as low as 2.5V (resting voltage).

See page 5, line 2.5...

Matador

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