charging: harbor freight Hercules 20v 2.5ah lithium battery using benchtop psu cc/cv

[@jasonbrown467]

IMPORTANT FYI: I am pretty sure that i eventually realized that the battery packs do not have an internal bms. A bms would keep each cell of the pack balanced via top down balancing. If you use the oem charger your cells will get and or stay balanced. if you use the method i showed above there will be no balancing involved. you dont have to balance your cells every charge, but they should be balanced occasionally. this topic is beyond the scope of this video and comment, another poster and I was talking and thought it would be a good idea to mention this stuff, and li-ion cell balancing is already well covered here on youtube and can be further looked into if you like.

[@robbygammel124]

they do have a bms in the battery pack, i replaced my old 18 volt ni-cad chicago elect battery pack with a warrior lithium 18 volt (swapped out internal pack to chicago battery case) even the warrior has a bms!.

[@robbygammel124]

kzbin.info/www/bejne/gmPSpqaForCKaK8

[@jasonbrown467]

@@robbygammel124 god damn it, apparently im pumping out that misinformation like a politician

[@liquidrockaquatics3900]

You should check out the 4/8/12 amp hour batteries with the 21700 Samsung cells inside them. They will blow your mind. I am completely swapping my cordless tools over where I can. I can’t wait to see what they come out with. The 8 amp hour battery on the circular saw/ blower/ right angle drill/ angle grinder all not only get massive run time, but are balanced nicely

[@morenothing4u]

You should never leave these charging unsupervised. The safeties across all these tool brands are not implemented the same way as you found out with the low voltage cut off.

[@rj3075]

Should have bought some IMPACT sockets to use on an IMPACT wrench.

[@jasonbrown467]

i dont really remember what i did at the time, but i know i do have impact sockets now

[@rj3075]

@@jasonbrown467 No problem just messing with you. How did charging your batteries like that go long term?

[@jasonbrown467]

@@rj3075 shit, now that you mention it, i think i may found that the charger acts as the bms. honestly i dont remember. so cc/cv is fine in a pinch for new batteries, but if they are old or abused this method of charging will likely make a bad situation worse. i really dont remember, now you got me thinking i should take the video down, but then again most people dont have the stuff laying around to do this. as long as you use the oem charger occasionally to balance the cells i think this method would be ok, but only if you understand whats going on

[@rj3075]

@@jasonbrown467 I think you should just make a pinned comment or something explaining the long term issues. The video is educational on how to charge with a power supply if you’re in a pinch which I think is valuable.

[@jasonbrown467]

@@rj3075 good thinking!

[@sklee1644]

Thanks for sharing. What brand and model is your bench power supply? Do you recommend to get one?

[@JoshReynoldsWhoaSci-fi]

Thanks for posting! I've been looking at the Herc batteries for some potential projects. I appreciate you doing the undervoltage protection in your last video, very informative! Based on that info, I'm going to incorporate an external undervoltage protector into my plans. You mentioned that some batteries have undervoltage protection built in, which ones would that be? I read somewhere that dewalt has it in the tool. Do any brands have it on the battery?

[@jasonbrown467]

to answer your question about low voltage protection, honestly i dont know and/or i dont remember

[@JoshReynoldsWhoaSci-fi]

@@jasonbrown467 Hey, since commenting, I did a little research. In case anyone else is interested, Ryobi seems to be the only manufacturer that has under voltage protection in the battery pack. I’m testing out an inexpensive board with a variable low volt cutoff. So far, it seems to work as intended.

[@jasonbrown467]

@@JoshReynoldsWhoaSci-fi that sounds right. a case of new ryobi batteries made their way to my possession to harvest cells and i remember seeing all sorts of bms shananegens

[@voidisyinyangvoidisyinyang885]

@@JoshReynoldsWhoaSci-fi That must be why my 5 amp stopped working! Just got a new Hercules 2.5 amp. I must have over drained the 5 amp battery!! Dang - didn't know that could happen. thanks

[@JoshReynoldsWhoaSci-fi]

@@voidisyinyangvoidisyinyang885 Hmm, what tool were you using with the Herc battery? If you were using a Herc tool, it should have had the low voltage cutoff. The danger combo that I'm aware of is a Ryobi tool with a non Ryobi battery that doesn't contain an low voltage cut off. With Ryobi, the cut off exists in the battery whereas most other brands (with some exceptions) have the battery cut off in the tool which should include Hercules.

[@Dowan_Gim]

Thanks for the video.

[@leetomlee7265]

I just got the same bench power supply. The battery i need to charge is not the same as the manufacturer states on the batter: 21v, 2.0AH, 36WH. So When i mulitply 21 time 2, it is not 36WH. Do I follow the 36WH? When I powered it up to 20.44, WH is over 36. The battery is kind of hot. Is this normal for the heat? After about 5 minutes, I checked the batery, the volt was coming down. Does that mean the battery is no use because it can't hold the volt.

[@voidisyinyangvoidisyinyang885]

i used the herc vacuum and must overdrained!!

[@kylewomble1993]

Short your leads to adjust current on power supply

[@jasonbrown467]

these cheap psu's dont like that when that happens