ISDT Redefines the LiPo Battery Checker: BG-8S and BC-8S Review

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The BC-8s and BG-8S are two new LiPo Battery Checkers from ISDT. The BC-8S comes in around $15. Is it better than the dead-simple $9 checker I've been using for years? The BG-8S is way more sophisticated and even includes features like Qualcomm QuickCharge 3.0 USB charging and an SBUS signal analyzer!!!
Purchase the BC-8S here:
* Banggood - goo.gl/jzXWrZ
* Amazon - amzn.to/2zTyV8O
* GetFPV - goo.gl/dCx2UU
Purchase the ISDT BG-8S at:
* Banggood - bit.ly/2HQzmn5
* GetFPV - bit.ly/2Py7nx5
* RaceDayQuads - bit.ly/2yh8qep
* ReadyMadeRC - bit.ly/2NH5Wel
The $9 simple checker that I have used for years is this one:
* Banggood - goo.gl/zmSfnN
MANDATORY DISCLAIMER: I am a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for me to earn fees by linking to Amazon.com and affiliated sites.
Most or all links above are affiliate links, and I will receive compensation if you use them.

[@blainebenson7863]

Internal resistance would be nice to check. It is a quick way to make sure a cell isn't damaged and the pack still has plenty of life left.

[@venomoussvt]

was looking for info on the BG-8S and as soon as I saw you had a video i knew which i wanted to watch! based on your description and demo I ordered it last night while watching the video. Thanks

[@rl2109]

Thanks for posting this review, and thanks for taking your time to create it! You keep me informed and updated on the market; I would not have known of this product except for you!!! Well, I might have happened to see this MONTHS from now, but you put such info right in front of me! I (along with countless other viewers) am forever in your debt!

[@CrazyQuadBrothersP3]

Awesome stuff Joshua! ISDT makes real quality chargers etc. Your video’s are some of the only I watch start to finish. Thank you for what you do for the FPV community. Your the best buddy!👍🏻 Your everyone’s neighbor they wish they had. Keep up the good work.

[@kheshavdheereess5243]

Man, I never get bored watching your videos...You're like the IT guy who explains everything in simple words.

[@kiddrone8336]

I got the $30 one a week ago at a race, I fricken LOVE it! I didn't know about the battery GO technology, but that would be awesome to see in the future!

[@Norminal1]

Looks awesome. I ordered 2 before the video finished. Just to charge my phone is great but all the other features makes it a no brainer. Thanks Josh.

[@goballistik1]

Josh man! ..again thank you for the invaluable information. It's always a pleasure taking in one if your vids before getting my fly day going. Hoping your weekends will he as great as mine. Until next time... See you in the sky! STONEWULFF FPV

[@MrJarrod]

Purchase the BC-8S through your link and love it. I only have cheap lipo balance chargers. I have always suspected that they don't really balance the lipos that well . And I was right. Now I can balance my batteries before and after I charge and discharge . Great investment, Hope my purchase helps support the channel JB.

[@daveday5507]

You're not alone. My BC-8S came out exactly the same as yours and cenk_d. This is a form of quality control that I have not met before. At least they're consistent.

[@slitherixxx]

good review the thing had my head scratching for a long time

[@visioneerone]

I've been using BC-8s checkers along with FD-100 dischargers to test for packs with weak cells. The voltage histogram feature on the checker makes this possible.

[@KrzychOlsztyn]

I'm using one from months. It's Awesome!

[@jackdaniels7913]

I just got mine and can't believe I managed with a simple one for so long if you are using a cheep checker shell out the funds and realise what you've been living without! It's a true mist have!

[@bernfranfrancis3012]

The BG-8S appears to be the new Spektrum XBC100 battery checker which does as you suggested, monitor battery cycles and usage. Good insight.

[@policeswat64]

That bg 8s is very cool. thanks Josh

[@cenabitednbfpv587]

Mine just came in! Love it thanks @Joshua Bardwell

[@youeladamas7840]

nice Teach the smart batts do have nice safety and storage features. give the mini checker to a friend that likes to fix stuff it just needs a piece of foam inside for screen and glue its cover back or put in a clear shrink wrap. the big one is a keep though for sure

[@lgrip1lgrip178]

tried this unit on a seriously unbalanced battery, 31 hours later, brought the balance into check and then balanced charged the battery, alls good, Thanks for the review on this product,,,,

[@1989cranston]

31 hours later.. wtf lol

[@peterwoo2489]

For the functionalities it has, I think it should be marketed as an RC Tool not just a battery checker. Great job, ISDT!

[@deadmoo83]

Receiver checker plus antenuators would make a good setup for head -to-head receiver comparisons.

[@joeymarkgraf]

I bought a BC-8S a few weeks ago and it arrived w/the front & display off exactly as you described. I returned mine to the seller. This may be how they're coming from the factory.

[@josephmorelli3191]

Very nice review. I recently received my ISDT BG-8S. Honestly, I didn’t have any idea how to use it. To me it was a black plastic box in a white cardboard box...no manual. When it was delivered, I opened the box, couldn’t figure out how to get it to work, got frustrated, felt stupid and put it aside. While I was watching the video I learned how to use the thing. Only by coincidence I had bought the LiPo checker you reviewed & for once I was pleased I seemed to have chosen a quality product. Question, how “balanced” do we want our LiPoi’s to be? Right now I have small 2S, 30C, 300 mAh battery that I use to power a winch for one of my vehicles plugged into the unit. Earlier I had put it on my charger for “STORAGE”. When that was done I plugger it into the BG-8s. I scrolled through to balance. It’s reading 3.902 & 3.908. Please don’t laugh, but is it worth the time to get it to absolutely perfectly balanced?

[@MallyFPV]

The BG-8S is an essential in my flight pack now, so useful if you need to charge your gopro, hd cam or phone in the field and don't want to worry about not having your USB power pack charged up, just use your regular lipos :D

[@pukki34]

yo, I had this a few years ago on my FRsky FLVss and using taranis telemetry logging. Its kinda cool to see how much your batteries sag under load.

[@houstonfirefox]

Got my BG-8S in from Amazon. Although it was shrink wrapped, it had fingerprints on the screen and appeared used. Was very disappointed that it didn't come with the 9 pin connector for the 8s configuration. Returning it.

[@The_Unobtainium]

it would be nice if it has some sort of output capability to drive a relay when the battery pack is low, full and if come of the cells is under/over voltage and battery pack current sensor. This would be so nice as you can easily make a simple charger controller and it could also act as a BMS!

[@Nenzis]

I use the AOKoda CellMeter 8 with discharge module. Besides cell checking, a lamp array can be attached for discharging lipos. I would have loved to see that functionality. Maybe discharging will be possible on the new ISDT chargers you were talking about?

[@HansHenderson]

Missed a feature, I think unique? the BC-8S has an overvoltage / high-voltage alarm HVA feature. For when charging from an adjustable PSU or DCDC converter rather than a proper charger. Kind of a BMS substitute. . .

[@kirkglundal4289]

What's nice about the BG-8S is I can use the QC3.0 USB to power my TS-80 soldering iron in the field if need be.

[@Marginal391]

Thank you 🙏 ✔️

[@kinzokushirogane1594]

It is obviously for someone who wants something more convenient but it costs more. You get what you pay for pretty much. I don't have the need nor money so I usually just stick with my 3€ battery checker which is very small and not a big deal if I lose it, but in the future, the 30$ one may seem more attractive. Great video

[@bluescreamfpv6833]

Got the ToolkitRC M6. Can do close to everything you showed and more. It's also a charger with a 150w output which is okay with a parallel charging board. It's also just around 20 bucks 🤷🏼‍♂️

[@VilleF1N]

RunCam Split 2 review tomorrow? Also is the part 2 of Matek F405 install coming soon?

[@rawpicsfpv3516]

Will i still need this, when i already have the JB Parallel Chargingboard?;)

[@IndAudio]

Can you make video of wire connections and can we use this with balancer?

[@BobAlberding]

Batt Go sounds similar to the revolectrix bump charger feature where it stores the cycle history. The bump charge goes one step further and stores how you want to charge that lipo and it scans then you press one button to begin charging

[@JoshuaBardwell]

The difference (I think) is that BattGo stores the data on the battery itself. So if you have multiple chargers, the data is always correct.

[@lgrip1lgrip178]

this unit is nice from old school meters, meter accuracy seems to be more on target, and balancing can be useful specially when my charger is in use, price equals convenience as far as I am concerned,,,,

[@taniksambo1969]

Can this work like a bms if left on the back pack?

[@65chacal]

Hi Joshua, can you make a quick video on how to update the firmware of this Battery checker? thank you in advance.

[@cyranoidy]

thanks Joshh!!! please we are willing to see more of the battgo .. and we want to have that charsoon battgo, and the new infinity batteries in a new review of batteries ... we start to need an update for our old infinity 1500 quality price champions, lets see if we got anew fella out there deserving the quality price of the year badge!!! thanks for the vid

[@LangerFeen]

Is there an updated version of this video ?

[@roccocafa7872]

hi, i have an old old old charger without integrated lipo balancer, he only has positive and negative that go to the battery and stop. this is still an excellent charger that I use for nimh or nicd cells but it has the function of lipo charging, if you want to recharge a 4s battery pack, can i use this idst to charge it? balance after charge or during charge? OR NOT!

[@SimRacer101]

Hmm, the Cell Meter and generics a lot of us use already have a single row of pins just like that. That receiver tester could be cool though.

[@jordanbass3210]

i was thinking the same thing my $2 buzzer checker has a single row of pins to connect to

[@deadmoo83]

I think the difference is their connector actually grips the balance connector. You need to hold the $2 checker in place manually.

[@LACCALIFORNIA]

Quick charge yes!!.. especially with your carry on lipos. !! : )

[@K1LLAC1TY]

Hey do you know if the mini omnibus f3 stacks for micros give out full telemetry? I did the firmware update on the new r-xsr i inverted and uninverted the smart port wire to the board and still wont get vbat on my leader 120. I believe its an omnibus f3 mini fc.

[@hunterzent3460]

What about the temperature ability? I can’t find a plug with a temp sensor already attached.

[@1337flite]

Apparently there are BattGo batteries listed on Bangood. NO idea how good they are but there was a post on RCGroups

[@gearstil]

what is the minimum value for low voltage alarm? Is there a way to cancel the alarm?

[@umbratherios5614]

mine drifts... a lot. during the balance, whenever the screen goes off and I click a button to "wake it up" again, the voltages are all reading wrong. if I reset it by taking off the battery and then plugging it in again, it goes back to normal. I find this very fishy. No, it's not the cells balancing out, because the voltages are all drifting about by 0.03v over and under the voltage when I turn it on. when it's turned on the first time it is dead stable... but after a short while it goes nuts.

[@65chacal]

Hi JB, can you help to upgrade the firmware on ISDT BG-8S and ISDT Q6 Plus ? thank you

[@kaynetta1]

It says it will check a 1S battery i have not figured out how to do that or mine doesn't work properly. I connected the 1S to the first 2 pens with negative on the first pen and positive on the second nothing happened.

[@mxmilkiib]

Typo in video description; "Purchase the BC-8S here:" is repeated

[@alexu5329]

Which battery configuration are you using for test?

[@jackdaniels7913]

At $30 it seems like a lot but in the long run it's so worth it if your in the lipo hobby in any way... I just picked mine up in early 2019 and man you just don't know what you were missing tell you spend the little extra for a top quality product like this and the hours x10s... just hands down worth the price in the long run ... hands down 🍻 cheers 🍻

[@jackdaniels7913]

That's true but unless you have a better one in mind I'd recommend it! The full color screen and XT60 plug are nice for using the USB charge feature and the size is smaller then I thought... but hay to each there own i just dropped $200 plus on a isdt t8 with 24v power supply and to say it ok is an understatement isdt is quickly becoming my favorite manufacturer next to armattan the price is higher then I'd like but it's worth the $$$ i hope you make an informed decision and if you do go isdt i hope your as satisfied as i am with them! 🥃cheers🍻

[@balee7774]

So now there is a spektrum clone of this that looks intersting. I learned of it first, and then this IDST by accident. If I am not wrong, this ISDT still has a receiver tester function that the spektrum does not. Very Curious. Great Video!

[@trif55]

all Samsung's since at last the S4 has done that, that was prior to the 9v QC spec, it did 5v2a when locked and 5v1a ish when unlocked

[@scottintexas]

How does this compare to the toolkitRC MC8? Which is better?

[@wadestewart3042]

Hi Joshua I just looked for the BG-8s on Banggood & right there with it are BattGo smart Batteries. P.s. I will be getting one of these not for the BattGo tech but I like even numbers🤦🏼‍♂️

[@darwill7834]

Does this test the internal resistance?? Cheers

[@tjburke79]

The futaba battery checker that I have been using for yeeears has a single row of pins

[@ng-iq4kx]

Progressive Rc has a I R checker. Cost $149. Isn't batGo same as what dji and spectrum do with the batteries?

[@hing983]

hi can a isdt 8s lipo charger use for 6s configuration

[@tannerbeard2840]

The $6 cell meter also has a balance function

[@richardnanis]

Thanks for the good review. With one point you are telling i am not sure: at 4:24 you explain the balancing and say "it draws current from the high cells and pushes it into the low cells". Are you sure it works like this? I would guess it just burns the energy of the high cells into load resistors and its not charging up the lower cells with the energy of the high cells. If so, it would be really a good device and worth the money. Please can you double check on this point and make that clear?

[@CORZER0]

Would you double check that for us yourself and report back? That would be great. Looking forward to what you discovered, because I really don't want to have to look it up myself. Thanks a bunch.

[@dunncalum]

@@CORZER0 that would be an active balancer, not a bms that pulls from higher cells for lower cells to use less power than resistors to dump power

[@SHARK1202X]

Is it bad if a battery is .05 off? Isn’t there some room for error? Or is everything exact?

[@captainfuture9055]

What is the black thing stuck on you battery cable?

[@tonibarros757]

My favorite, till this video, was the frsky one.....Precise and quite....No buzzer screwing with ur head, and a nice oled screen. And Tiny, btw.

[@jean-guyouellet9658]

So, none of these measure IR.! Anybody know a tester with an IR integrate. Actually that's what i'm looking instead of plugging the battery on the charger all the time.

[@yali123]

Can you please clarify what powers it? Does it have an internal battery and needs to be charged, or does it use the tested battery voltage, which in this case drains it?

[@JoshuaBardwell]

It uses the tested battery voltage to power itself.

[@DoserFuFPV]

hi Joshua, does it read cell internal resistance? thanks your time! ;)

[@JoshuaBardwell]

+Doser_Fu FPV no

[@frangalasso8301]

Do they cell the battgo xt60 separate so could convert them on your own?

[@JakubKraus0]

The battgo chip is in the battery, not the XT60 (even though it was in the advertisement material). So even if you bought that XT60, it wouldn't do anything

[@callmehank88]

How long does the BG-8S take to balance a cell or two that are maybe out by 15-20mV for example?

[@JoshuaBardwell]

I haven't tested this... to tell you the truth, I just balance when I charge.

[@tizio5103]

Epilogue: It's been three years and there still aren't any BattGo batteries.

[@Utube2Itube]

Spektrum Smart Batteries are probably using that standardisation

[@eksine]

I have Battgo batteries that I use in the Battcave when I pretend I'm Battman

[@Utube2Itube]

@@eksine The Battgo batteries will make your Battmobile go crazy fast 💨

[@Utube2Itube]

@@_mr_andersson Exactly, that’s what I thought. Seems to be a very cool technology. I like the automatic discharge function and the information about total number of cycles. I wish this was used by all manufacturers these days.

[@carlosreyes6448]

I bought one but didn't come with a wire harness

[@ehunter2010ed]

I don't think I heard you say that either of these check lipo resistance they should have added that feature at least for the 30 dollar one. I know lipo resistance is pretty much the most important info to get from your lipo for me anyway. Also that batgo seems cool but shit I either smash my packs all up or run them to hard and end up with crazy high cell resistants or usually both.

[@davidsagal]

Hi Teacher. Could I use BG-8S or Q6 Plus to charge my GoPro 5 session?

[@JoshuaBardwell]

Yep, for sure.

[@ksrnate]

The Last thing I'll ever want do in my life is plug a lipo into a pc and see every charge and discharge cycle it's had. But I like the isdt checker very nice 👍🏻

[@zymurgyjwt]

All I want is a battery checker that will discharge/balance to a set point. It would be nice to throw a battery on and have it balance down to 3.75 a cell. That way all my packs are the same when I get home and want to parallel charge.

[@JoshuaBardwell]

+zymurgyjwt stay tuned to this channel...

[@coppercopter947]

I think it does discharge/balance from another review I saw. Can Joshua confirm this?

[@mrSErgezen]

Just get this one: www.banggood.com/nl/AOKoda-CellMeter-8-150W-Discharge-Module-Set-with-Lipo-Battery-Balancer-p-1196376.html?p=6417065352572014042K Its cheaper and does what you want to do. I do own this one myself btw. Make sure to create something to protect the lights they get hot..

[@bobravenscraft5376]

Like I stated I'll stay with imax only thing to balance capacity 15$ bro

[@bobravenscraft5376]

Check the $ you'll stay with imax I build batteries this is when you have more money than sens

[@FPVSkittles]

Joshua - on the BG-8S do you know if there is a way to check the voltage on a tiny whoop sized battery? It says it will do 1s but idk how to make it read out the voltage. I have connected a separate battery to the XT-60 to give it at least 5V but when I connect the tiny whoop 1s battery via a JST like shown in the pictures of the product I get no voltage shown in cell #1. Any ideas?

[@JoshuaBardwell]

I'm not sure how that would work, honestly.

[@joelromero1795]

As far as i can tell the xt-60 and the balance plugs dont run on a closed circuit. I just tried this on a sacrificial whoop battery :) plug in a normal battery, in my case i used the 12v power supply for my ISDT charger, plug the xt-60 in to the BG-8S and plug in your tiny whoop battery (1s) into the balance port, i used a servo adapter to PH 2.0 IT WORKS! the 1s battery survived and i got an accurate read out from the cell checker.

[@FPVSkittles]

Joel Romero I am making a connector with a extra balance lead - I hope it works as well! You used the top two pins correct? Thanks for the info!

[@joelromero1795]

Yeah the top two closest to the xt-60. start with ground then power. Glad i could help!

[@JamesLewis]

My screen also came off... before I even received it... had to glue it back.

[@Crisposhot]

I use the bc-s8 on regular basis and also balance the cells by default. I think you had bad luck with yours as mine is in good shape and not falling apart. Wouldn't recommend to install on a quad either. As always, great video and useful information.

[@JoshuaBardwell]

+Manuel ortiz several others are also reporting that theird came with the front off.

[@Crisposhot]

Joshua Bardwell oh that's a shame. Guess its a matter of time form mine come off

[@AustinChopra]

there is some battle batteries out there if you go onto bang good and search for "Charsoon BattGo 14.8V 1500mah 80C 4S Smart Lipo Battery XT60i Plug For ISDT Linker BG-8S T8 Charger" you should find it

[@yakiyee]

hey josh i'm planing to buy your parallel board and i'm using the ISDT SC-620 How would you recommend to put 2 of your boards together in parallel and still be able to charge 12 batteries at once Thanks in advance

[@JoshuaBardwell]

+yakiyee just daisy chain them with an XT60 and a 4s balance cable.

[@yakiyee]

ok thanks

[@ssaxin81]

Joshua how about testing the basic accuracy of this checker, measurment with 4.5 digit dmm would be nice.

[@JoshuaBardwell]

+Eddi Maevski I'd need a calibrated meter to do this, right?

[@ssaxin81]

Yes, I usually borrow from my full time job overnight...

[@jaakko200987654321]

does the usb charger function work with only the JST XH connector plugged in?

[@JoshuaBardwell]

No

[@jaakko200987654321]

@@JoshuaBardwell ok, thanks for the fast reply :)

[@joedanero5360]

I don't get owning a separate cell checker. I have an ISDT SC-608 balance charger and its small enough to carry to the field and use to check cells or charge packs from a car battery.

[@ASJC27]

A battery checker is much more convenient and fast. With the sc-608 you have to plug in a separate battery to power it up than plug the test lipo and scroll to see either the individual cells or the total voltage. With a checker you just plug in the balance port and with the better ones you immediately see everything you want. I use the aok one that also doubles as a fast discharger. I also take an sc-608 with me but would never use it as a tester. It's just a hassle. A separate tester is also very useful to match batteries if you parallel charge.

[@joedanero5360]

Unlike the ad pictures of the sc-608, the voltage and separate cell voltages are all displayed together on power up. No scrolling. Plugging in a separate battery or using the same battery that I'm checking is not a hassle for me. I don't parallel charge.

[@neomayad]

This vid is a few years old. is this still the best bang for your buck or is there something better out?

[@armani007E55]

Dunno I was going to ask you the same question? :)

[@neomayad]

@@armani007E55 i got one and I absolutely love it. Worth every penny

[@armani007E55]

@@neomayad I'm sold! Tks brother!

[@abizi1879]

i need some advice... 2307 or 2207 motors on the evan or 5152. also, 2522 or 2700 kv on either of the motors?

[@JoshuaBardwell]

If you get 2307/2700kv, I hope you have a big budget for batteries.

[@briancase9909]

Are you starting to fly around with 5s batteries now? :-)

[@JoshuaBardwell]

+Brian Case no. That's just a field charging pack.

[@elninonitro]

Does it support an external discharge load? That would be the clincher for me.

[@JoshuaBardwell]

No.

[@knolagon3094]

does this isdt charger come with a warranty? i bought one on reccomendation and it will no longer turn on no matter what size of battery or charger i pplug into it.

[@JoshuaBardwell]

I would try posting on the rcgroups thread for the product. Or reach out to the company you bought it from.

[@Toogo4]

On all the ISDT the percentage shows different (higher) with all the others out there. It show way too high, I killed some lipo's by only looking at the percentage.

[@davidsagal]

And what charger do you suggest me for home or even better for home and field? Maybe Q6 or T8? Thanks Mr

[@JoshuaBardwell]

I think Q6 is the best value for money. T8 is a great choice. Maybe overkill for field charging. And if you don't intend to parallel charge large amounts of packs, T8 is probably overkill.

[@davidsagal]

Joshua Bardwell 👍 So...If I choose T8, for home, how many time would it take to charge a 4s 1300mAh Lipo with a Laptop power adapter of 18.5v input 65W and 3.2Amp?

[@tygrouxfpv9758]

Hi Joshua, Can I use isdt FD100 with bg-8s in same time for balance cells? Thx

[@JoshuaBardwell]

I think the BG-8S works so slowly that it is not likely to throw the FD100 off. So it's probably okay. But personally I would do the FD100 followed by the BG-8S. Actually, personally, I don't see why you would care if the cells are balanced if the pack is at storage. Balancing really only matters when you are charging the pack, not when you are putting it in storage. As long as all the cells are close to 3.8 volts, I don't think it matters if one is a little higher or lower than the others.

[@tygrouxfpv9758]

Thx for your answer.

[@K1LLAC1TY]

any idea why my isdt 300watt charger on you jb parallel board not balacing properly?

[@JoshuaBardwell]

Plug in a battery directly. Does it balance right? If so, the charger is fine. If not, the charger is defective. Check with a multimeter (NO BATTERIES PLUGGED IN TO THE BOARD) that the balance pins on the board have continuity to each other. In other words, all of pin 1 on all of the balance plugs have continuity. All of pin 2. Etc. If a trace on the board had burned, the packs plugged in past the burned point would not balance that cell.

[@K1LLAC1TY]

Joshua Bardwell thanks

[@TroyNahrwold]

Can this "save" a bad battery? I've had batteries that sit (not at storage change - shoot me) and I pulled them out of the drawer to one dead cell. My charger wouldn't even try to charge the battery. Could the auto-balance function possibly save/fix that battery?

[@JoshuaBardwell]

+Troy Nahrwold the way to fix it is to charge just that one cell at low rate via the balance plug. You need to rig up a 1S adapter to stick into the pins on the balance plug. Once the cell is matched with the others you can charge as normal. But this is a bad idea. The damaged cell will make the battery perform bad. It will get hot and may not be safe to charge.

[@TroyNahrwold]

Joshua Bardwell thanks for the info. Good to know both that it can be fixed, and that is probably not very safe.

[@rogue-tr]

I've had this happen to me briefly on two separate batteries. If you set your charger to "charge only" where it ignores the balance lead, you only need to charge briefly at a low rate for even only 10 seconds and then switch back to balance. The charger will balance once it detects voltage. Both batteries recovered and have gone at least another ten cycles. They don't perform overly well but they never really did :) ... hard to tell any lasting effect. In the past I have just drained them, shorted them and tossed them thinking it was a write off. I'm sure there are worse scenarios than mine but I reclaimed two batteries and worst case I have them there for the TS100 if I deem them too saggy

[@ForPropertyInvestors]

How can I connect this to 4s3..2v 300amp hr lithium battery pack and could I keep an eye on and balance them with it. What’s the name of an actual lead that connects to the battery terminals and to the device?

[@JoshuaBardwell]

The name of the lead is a balance lead. If you search for "4s balance plug" you will find it. That's not the official name of the plug but it will get the results you want. Using this to balance is extremely slow. Especially for a 300 Ah pack. You really should use a charger to balance the pack.

[@ForPropertyInvestors]

Joshua Bardwell Thanks. It will be constantly connected to a TS-45 solar charge controller programmed for lithium. So this will be regular charging in days of sun! Is this all the batteries need to stay balanced. Why do ppl sell BMS and Active Balancers if this all it takes?

[@leonduquenne6224]

You say it can fast charge, but my phone doesn't have that. Can it also charge it?

[@JoshuaBardwell]

Yeah no problem. It does standard charging too.

[@WoodRite1]

Can you check 1S batteries on the BG-8S and if so how?

[@JoshuaBardwell]

If you were to build a wire adapter to adapt the 1S plug to a balance plug, I think you could do it. But I've never tried it myself. Here is what I use: amzn.to/2TTAIEK