Repair Makita BL1830 Battery By Making One Good From Two Bad

In this video I'll take two bad Makita BL1830 lithium batteries and will make one good operating battery. Plus I’ll show you two ways, how to solve protection circuit problem, when it was triggered and regular Makita charger isn’t charging battery any more.

Due to factors beyond the control of WellDoneTips, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. WellDoneTips assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. WellDoneTips recommends safe practices when working with the tools or equipment seen or implied in this video. Due to factors beyond the control of WellDoneTips, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not WellDoneTips.

[jeroendullers]

This battery reconditioning program exceeded my presumptions. It worked on any drill battery, several AA and AAA batteries batery.repair and any camera battery. The steps are simple and the act itself is exciting to do. No matter what type of battery you`ve got, it is sure to function again!

[patcruz]

You are one of the few who have shown how to test each cell, soldered the batteries back in place and shown when the circuit protection board need replacement as well. Many thanks for a very well explained video and the links for parts.

[malibu]

This is a great video on this repair.I've done about 10 of these battery's now in the last year and a half. Alot of them seem to fail again. Ether the replaced cells go out or they create the next weakest set and those will go out. I put them all in balanced when I do them. Its to bad the replacement (board chip pcb) doesn't balance all the cells on each charge. If one set drops a little lower it boosts the others up. Eventually when it gets to low it will cause the replacement board to fault (flashing lights). But on the bright side you can change the bad low week cells again or separately charge them and it will start working again. It Doesn't lock you out. I think the best way to charge the mixed matched used cells would be to use a balance charger to keep them equally charged. Sometimes the battery's show its fully charged on Makita charger but is still weak when being used with a tool.I have taken it apart again and one set of cells is weaker. The Boards i have been using were from different supplier look the same but the temp sensor is longer. Sorry for the long post.

[leonlester]

One of the best and knowledgeable videos on 18650 li-ion battery repairs

[Silveradost]

Thank you for the valuable information. Good thing I checked before recycling two of mine that just went bad after 6 years. I think these are the same cells I use in a vape. Now I have two paths I could take :-) Great video, well done and thank you again for your time and efforts.

[gabrielgarsea]

FYI to remove Makita Bl1830 battery screws use a Torx T10 security bit (it has a hole in torx bit center).

[idksomethingunique]

Just did this mod to a water damaged battery, works perfectly!

[ruudmobile]

Excellent advice... really good source for fixing my dead bosch cells... thanks a lot!!!

[simonm]

There is a Chinese company called LLC electronics, they offer a set to make a Makita LXT battery, you get a case, the cell holder, prefabricated nickel strips and a PCB with balancing. With this there's no need to use a 3rd party charger for balancing, it is done by the Makita charger automatically.

[mackobun]

Great video. Thanks for taking the time to walk us through.

[larmar]

I've charged each pair of cells after replacement, and the makita charger accepted the battery with old circuit again ! :)

[scottbaker]

If your Mikita balance board doesn't like the charger it could be over voltage (Mikita only charges the cells to 4.0v) or it could have tripped the failed try counter.
There are several versions of the Mikita battery balance board on eBay, you installed the old circuit board that only removes the battery from the load when the #1 cell gets lower than 3.2v, on a new pack that previously had cell balancing. I took apart 8 packs and made 5 working packs.
I've got some new design balance boards on order for my older (junk pile) pack that now has a failed board and some mismatched laptop cells.

[rodwalpole]

Thank you if only l'd have the gear and time, good vid mate, and nice work, Cheers.

[jed]

Good video all round. I do wonder if you could have checked the internal resistance of the two "good" replacement cells. One of the cells in the final test had higher than average internal resistance (and thus had lower voltage) and it may be that one of the batteries you installed. Testing the donor batteries before they get soldered in is doing due diligence. I learned a lot from your instructions and I thank you for time and effort, much appreciated.

[sophiesoloway]

I have a working Makita battery which the yellow tab on the circuit protect board has broken off. Would I be able to buy a new circuit board and just swap the whole piece out?

[rhiantaylor]

Given that the Makita balance board will not let you replace cells and the replacement chinese boards do not monitor individual cells so cannot balance the battery, I feel the only viable way forward is to connect to individual cells with one of the connectors used in the R/C world and then use something like an Imax B6 to re-charge and maintain balance on the battery.

[PolakeXD]

You have to watch out because there are similar Makita batteries which have charging cycles logger. I heard that there is a easy way to bypass the counter or reset them but I forgot how to do it...that's why I run my Makita battery pack with an Amazon BMS and XT60 connector in the drill and battery

[silverssonyoutube]

If you replaced all the batteries without putting a new board on do you think it would have worked?

[Home_made_ch]

Did you realised that cirquit boards have different contacts. Looks like one battery is with star, second without. Middle connector at one have two contacts, and second battery Middle connector only one contact. My impact driver does not work with battery with two contacts. Work only if battery fitted not fully. So battery will start charging after this, but tool may stay without battery if it need two contacts instead of one

[shin-ishikiri-no]

Does anyone know what the two small holes (with metal inside) on the Makita power source terminal are? I understand the two metal contacts (+, -) but I don't understand the two tiny metal contacts. My 5.0amp 18v battery doesn't have any visible contact ports that match. Maybe that weird little white box/white wire on the left at 4:40 has something to do with it? Is there any wireless connectivity going on? I ask this because the power source terminals from Japan and the U.S. have a very slight difference. If those extra metal pin holes are inactive, it seems like the US battery should work with a Japanese terminal.