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Mikita lithium battery repair

Mikita 18v lithium battery repair? Im surprised there is not a section on tool repair. I have a Mikita 18v lithium battery that has a known flaw. The chip in the battery pack if drained dead or sits to long will brick the battery permanently making it unusable. This is a known problem with a class action case. Problem is there is a lot of these batteries going to the landfill that are perfectly fine and just need the chip reset/bypassed.

Update

The charger model number is DC18RA, the battery model number is BL1830, my battery is an 18v 3.0 ah Li-ion

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krshome, I would like to recreate this condition. What model battery do you have and what model charger are you using? I think this would be a great guide to create and may be keep some of those batteries out of our landfills (and money in your pocket).

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I waiting on a security bit set to get it open. Really want to see if there is a fusible link somewhere, if not Ill send you the battery. I still need the charger though. Give me a week or two to get to it. I'll sent you the model numbers as soon as i bring the battery in outa my truck.

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Hey there,

We'd love to tackle exactly these kinds of issues, but we just don't know every flaw for every device out there, nor can we document every repair project with our team of six tech writers. Something about them needing rest on weekends, or some b.s. to that effect.

So we have two paths you can venture down in order to help:

1. You can create a guide for this yourself, and show folks exactly how silly-easy it is to fix the Makita batteries. Start by going here: https://www.ifixit.com/Device/Tool

2. You can donate a device for this cause, and have out technical writing students create a set of guides for it. See our Device Donations page for more info on how to get that stuff over to us.

Thanks, and happy fixing!

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The fact is that the fusible is open now, you could bypass it but a hazard waiting to open. Does anyone know the value of that fusible link so we can just replace it. Then pcm will operate as normal once the first two dead cells have been replaced with heavier duty cells. But not too heavy that you unbalance the battery

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dazza, got a model number for the battery? May be we can reverse engineer that beast

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Yeh BL-1830. Charger is DC18SD. Ive since investigated further, fusible link fine. 2 dead cells. Need to reset processor. If an aftermarket charger works. That would sort it. But risky depending on how it is rigged. I have 8 dead ones & im a tradey. Past experience in electronics & want to try & sort them especially at a hundred bucks a pop. Would love to hear some more ideas.

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Here is the data sheet of the fusible link:

http://tomsyty.pl/datasheets/s/sc_protec...

Before going to all that trouble, first check if the batteries are ok. You can measure them on 6 points (3 measurements). See this picture (not mine): http://3.bp.blogspot.com/-APU6zZech28/UV...

If one pack measures 0, you should replace them before replacing the PCB.

Batteries can be bought here: http://www.ebay.com/itm/221450603563

New PCB here: http://www.ebay.com/itm/Makita-18V-BL183...

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Thanks bud. Ill have alook at it. Ive swapped the first 2 cells.

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Unfortunately data sheet wouldn't download. What format is it in

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I haven't found out how to replace the chip yet, but I have charged my dead battery using light wire allagator clips and small steel washers hooked up to a charged battery in parallel.

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Hi everyone. I have had exactly the same problem with my bl1830 battery. I spot welded in (don't solder Li ion cells as it's much too risky) a new Sony Li ion 18650V cell as one had vented. All other cells tested fine. Battery was recognised by charger and charged OK. I used it and then tried to charge it and charger didn't accept it. I then charged it via my regulated power supply by bypassing the bms to 18.8 volts. I then put it back on to Makita charger and it was fine. I have purchased a new bms from China which doesn't have a suicide chip on it. The new bms boards you see on eBay don't have a individual cell balancing feature. They seem to work OK by giving protection to the whole pack. Testing these batteries reveals that they self balance reasonably without too much deviation. Seems that using these retrofit bms chips and replacing duff cells is the way to go to get more life from the battery. I'm lucky as I get a free source of high quality Li ion cells from faulty e bike batteries. Just be extra careful with Li ion and read up on safety precautions before tinkering!

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It is technically possible to replace chip firmware on the Makita bms if you can read it and reflash it. Or replace entire chip if you can hot-air solder. Seems like a lot of work thou compared to putting in a new bms board. Would be interesting to see if someone has actually done the chip read/write thing.

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Hi does anyone have a circuit diagram for the battery 1830 and charger dc18ra? I have one but cant read the component values.

jcpreston22@gmail.com

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krshome will be eternally grateful.
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