Comparing 18650 cells for DIY battery - Q&A#5

[@JohnDoe-pv2iu]

This is a good explanation of how to consider cells. When I build a battery pack from recovered cells, I always have 'culls' that test better or worse than the majority. I use these to build 12 volt starting batteries for lawn mowers and such. I usually stack a bunch in parallel (6 or so) and do 4s. That gives me plenty of cranking power and it is only used Very briefly. I am probably stressing some of the cells but it is so briefly that they don't have time to get hot. One of these batteries has been cranking my zero turn for years and it was made from cells that were 'outcasts' from my regular projects. Take Care and be safe, John

[@pjr2481]

I am very interested in your book, I’m new to e-biking. I suffer a severe back injury and had to have rods inserted into my back and portions of my l1andl2 vertebrae removed. I’ve gained weight and want to get into some sort of better physical activity and I’m in college so an e-bike serves me for both transportation and physical activity. The downside is being a student and partially disabled money is tough to come by which is why I am looking to learn how to keep things cheap by providing my own labor in all building processes. You’re video was the most straightforward and easy to understand I’ve seen so far. I thank you and look forward to seeing more.

[@melvinbelcher7606]

A battery book would de nice. I always have questions but I am watching all your videos

[@Team33Team33]

At last someone who has explained this comprehensibly.

[@janliljeberg3769]

Thanks for most instructive programs, they are so useful to me in understanding who I should think now when I'm on my second ebike, more suited to my needs.

[@vehicle53]

What do you think about the LG HE4? My current battery is cutting out on steep hills. I'll try and lower the controller max amps first but I'm thinking about replacing the cells.

[@snappyjunexzy]

Does 2 packs of 60V paralleled batteries adds up power compared to non paralleled(1pack 60V)?

[@roach6791]

Hi Mikey, I have been playing with mini FPV drones lately and am definitely more interested in alternative modes of transportation. My mom's boyfriend saw my interest and approached me about building a ebike for him using one of those Bafang ebike kits. Going with a 750W motor what size battery pack do you recommend I build? Keep in mind this will be my first time battery build. Thanks a lot and great videos by the way.

[@daccacheabdo]

So much info in a short video. I love it 👍👍. You got a new subscriber

[@neutralmtv3644]

Micah how to match up bms for the battery you build can you make a video?

[@longbowandwarbowcraftingbo2859]

hello micah i recently purchased youre book on how to build lithium batteries and i must say it's very easy to understand and is well put together. i have recently dismantled an old 36v ebike battery and tested all 50 cells. i shorted some in the process and the voltage levels vary greatly???some are 4.2v- 4.3- - 4.07v -3.55v? which ones should be ok?

[@jerrehmanneh4499]

Hi mikey. If you buy a ebike conversion kit. Should you open to battery to see if its good quality or just take the manufacturer's word for it.

[@mrdudeccs]

Great Video, This is exactly what I needed 5 months ago. I did get your book and that answered any battery questions I had. I may have to get your other book, because my controller is kicking my butt. I cant get the motor to turn, I think it is the controller.

[@timekeeperg2112]

Hey Micah ... I will be buying your battery building book but before i do , my intention is to use 21700 cells with a 5000mah either lg or samsung from a canadian retailer. They retail for approx 8.50 each. I cannot buy from the usa because of senseless brokerage fees as well as other rip off fees crossing our shared border. I want to know if u have a better source for the cells and do you recommend the new 21700!!! Ty for your help!

[@russelllujan4778]

Hi Micah, My son rides a Razor MX 650 electric dirt bike which has 36v system consisting of three12v 12ah AGM batteries inside. The batteries are very heavy and needles to say, had a very short life span. Is there a lithium battery that can replace these AGM batteries directly and can you recommend a lithium battery charger?

[@ottograff3986]

I want to build a long range battery pace for my single hub 450 watt skateboard witch batteries and what configuration do you think would be best? Thank you.

[@emmanouelchatzinikolaou1687]

I am new in this subject . You are a grate teacher. Thank you. I am wondering if I can use again the bms module I take out of the lap top battery I recycle. Thank you again.

[@likeher9]

Hi Micah I've learned so much from yourself over the last year or so starting has I did 18 months ago knowing 0 about Ebikes! Thank you for that. With all that in mind, I've just - with help from others put together a 52v 28ah 1000watt rear hub home build. My speed controller is a 48v 45amp Sine wave, My cells are LG MJ1. Question 1. Is there a weak link in this build? My thinking is the motor? Question 2. With that in mind, should I jump to a 1,500watt rear hub motor instead? Please could you spell out the pros and cons in this thought process. Will the 1,500 watt motor give My present setup any more performance? Thank you in advance for your help Micah.

[@ZetLAW]

Hey mike I was wondering, two things regarding batteries. 1. Why you only need to balance the batteries in the series and not those in the parallel ? 2. When building a pack do you fully charge/discharge the cell before putting them all together ?

[@rexczi6299]

1. In parallel the cells have the same voltage, therefore its no reason to balance them. They charge and discharge themselves, so they all will be (for example) 4,18v if they are fully charged. 2. No? Why would you? If you want to check the capacity, go ahead and discharge them. It doesnt matter if your cells are empty or full when you connect them I aint no expert, tell me if im wrong please

[@czarzenana5125]

1. It is best to balance all batteries. In practice: do not mix batteries. Use new batteries of the same brand and type and if possible from the same batch. 2. When building a pack make sure all paralleled batteries measure the same voltage before you connect them, otherwise one battery will load the other with a current that might be too high and blow it. You could use a power-resistor to equal out differences between batteries. You can also use a 3V or 6V light-bulb instead of a resistor (do not use a LED).

[@ironryan2009]

Thanks, fantastic content as always. I would love those books to learn more. I’m looking to replace my 2 year old battery which is a 52V 15AH Hailong with Samsung 30Q cells. I want the same amount of power, acceleration maybe a bit more range like 17AH if possible, but with a smart BMS so I can keep my eye on the cell voltages. I’m running a Bafang BBSHD motor which is capable of 1700W Can you recommend cells, BMS and provide and advise for making such a battery in 2021? Thanks!

[@LeoHeiland]

Hi Micha, Question, How important is it to use protected 18650 cells? Do most commercial packs include individual cells with protection?

[@1973canim]

Hi, First of all great channel. Now i need some advice. I want to make 2 6s 18 to 20mah batteries for a jet surfboard. Well, this is a tryout. Budget is also an issue. What cells do you recomend? Thanx

[@Peacenet22]

Hi brother Micah,love your videos so much. A small doubt from my side, what is the difference between capacity of the battery and the max current from the battery. how they are connected each other. I just want to learn it from you.

[@jordantan9487]

Hi Micah, thank you so much for producing all these fantastically informative videos. If i built 2 indentical 10.4 Ah battery packs, can i connect the discharge cables of these batteries in parallel to get a 20.8Ah pack and yet keep the charge cables separate so that i can use 2 separate chargers to charge the pack so that charging time would be halved compared to charging a 20.8 Ah pack through one charging port. Thank and God bless

[@praveenkumarva6320]

How best I could design battery pack for 52v for 180A controller, Caz iam confused in selecting BMS, whether I should split voltage or max current for creating multiple packs.. Please help me with this

[@Hundert1]

What's a good mR reading for brand new Samsung 3000mAh Q30 18650 15A button top unprotected batteries ? My Zanflare C4 charger tester gives the internal resistance on my supposedly brand new Q30s as 2.80mR, 1.90mR, 2.14mR, and 3.02mR respectively. Thanks much

[@julikb]

is it good to have 2 bateries x10 Ah instead 1 of 20 Ah ...and when you ride small distance taking onli one of bateries (light weight) and the other is at home and maybe charging .when you need tak the other in the bag or connect both on bike?

[@RollingThunder85]

How much difference is their between these cells and the lipo packs for rc cars is there a more cost effective diy battery for rc hobbies?

[@lbenegas]

Is there any webpage with centralized specs for the majority of cells out there?

[@samkumar486]

Thank you and I really needed your help... hope I will finish my project...

[@TheJR914]

Nice explanation of the cells. Where can you purchase the individual cells in the USA. Typically 18650 LiFepo4? Nice presentation keep up the work.😀 John

[@dalehall7139]

Another great video Micah. My question has to do with the biggest enemy: HEAT! On my 10 mile commute, I've noticed my battery is starting to get a lot hotter than it used to. Had this pack for 8 months now, and the weather is getting warmer. Also there are a couple of pretty steep hills in my commute. Could you explain why the heat has suddenly started to get noticeably worse, or better yet explain why this happens? Thank you and have a great day!!

[@EbikeSchool]

Hi Dale, do you have an ebike shop in your area or some professional that could check your battery? The heat is caused by resistance in the battery. There is always some resistance, which is normal. If connections become loose though, the resistance inside your battery could increase, resulting in more heat. That would be the worse case scenario though. It's also possible that as the weather heats up, your battery just doesn't dissipate heat as easily as it did during the winter in the cool air. Regarding the hills, your battery will always be under its maximum load on uphills, resulting in more energy lost as heat, so it is normal for more heat to exit the battery on hills. But if it is a sudden increase, I'd recommend getting it checked out just to ensure the battery is fine on the inside.

[@dalehall7139]

EbikeSchool.com Well I'm kinda on my own here as far as E-bikes are concerned. I built this conversion in September of last year, and since then have put 800 miles on it commuting. I them lived in a small town in Georgia that had 0 E-bikes. I moved from there to another small town in Tennessee with the same problem, no E-bikes. I have studied battery tech as much as possible, and try to stay in tune with what's happening with my bike as it is my only form of transportation. Short of taking it apart I have no real way of checking it out. Thanks for your speedy reply and keep up the good work, really look forward to your videos as they are a great resource for me.

[@seanschwab9715]

@@dalehall7139 i hear you, the reason i cant go to an ebike store or shop is because not many out here but there are some but i dont have the money to pay someone to do it, i grew up in Kennasaw GA, and now i live in seattle, plenty of hills. I have mechanical knowledge of how things work, this electrical stuff is kinda new to me. Closest thing ive tinkered with as a kid was rc cars. Im actually working out in my head how to make the air as your riding get to the parts to cool them. Corrugated plastic is cheap and durable enough for that. Problem scooping air towards the equipment that needs cooling, wind resistance. But i do think it possible to put a couple computer processor fans onto a solid battery box and suck or push air towards the battery. How much juice it would use to keep it cool may or may not save any energy. Probly the energy that can be saved would be powering the fans but a start of a good idea. But now how to cool the motor, its gonna be a hub motor. I know they get hot too, even being as exposed as they are.

[@binitbalakrishnan6239]

Hello Mikey, Your Videos have been extremely informative. Although,I wanted to ask,what battery configuration of 18650Panasonic pf would be able to cope with my 40A esc, with system voltage 24V?

[@EbikeSchool]

An absolute minimum of 4p, but much better to go around 6p, or even higher, if possible. 24V requires 7s. So a 7s6p would be good.

[@philliplawson9724]

HI, I have a old battery pack with 3.6v bms and wanted to know can I use it with 3.7v upgraded batteries?

[@LuisRamirez-zy2vx]

Hello so I was wondering if a 48v 36ah would be a good long range battery ? Don't really got many hills but some parts are pretty steep so idk if that would affect it's range ability

[@biomangarance4878]

Thank you very much. You're a great teacher.:-)

[@oscarcorrales1803]

Can I mix and match the diff Mah outputs? I have standard Pink, Green, Grey, and Red batteries all from laptops I’ve found here and there. I need to make two 12v packs or one 24v pack for a scooter that I bought my son. Any links on best way to do those would be greatly appreciated, would love your battier book as well! The scooter I have is an Astroid GT, thanks for any help

[@LEXICOGRAFFER]

Micah-It looks like I'm facing creating a whole new battery for a Curry IZIP Metro, bought used and looking like long dormant....I've removed and opened the battery case to find two rows of 20 cells plus BMS.....I bought your book today on Amazon and will take my time with this. But hoping you could translate what was printed on the cells (which, BTW, measured .7 volt each in random testing): They say "Samsung ICR 18650-22P SDI 1C13. Hoping you can tell me something about what the 40 of these equal and anything that comes to mind, about their quality or character, just to give a jumpstart before your book arrives. Much appreciated!

[@MontanaPreston]

I just wanted to say thank you and I really appreciate what you are doing. I am enjoying learning this stuff!!

[@SootyHunt]

Thanks for this vid…. I’m on a crash course in building An ebike…. Now I’m learning how to build my own battery pack. Fairly simple but I have no idea on how to work out how many cells I need etc…. This is a brilliant video to explain it. Now I can go back to my site…. Do some maths and order my cells…. Amazing, thanks !!! So just to confirm, the better the cell (mah and amps) the less cells you actually need to build your battery…. The cheaper the cell, the more you need to build too…. Is that right ? Anyone 😂 Thank you, excellent vid !!!

[@andreit.8912]

Hey Mike . If i’ll make a 13s4p with Samsung 30Q , can i power a 1000w motor wit 1500peak, or it will overheat? From your video this should go to a max of 60amps , right ?

[@pipito588]

hi,which battery is best for my 48v 750w bafang motor,(samsung,panasonic or china battery)thanks

[@thomaseidst3170]

Hi from norway :) can you mix the cells in a battery pack? If you have 68 of the one type cell can you then mix with the lower cell in the battery pack?

[@AustinOConnellVideos]

this channel is so helpful. thank you!

[@tbrindan]

My question is if the controller is rated at 26A. What should be the BMS rating for PF cells be. Should it be 26A or 40A? or BMS rating doesnt matter? Neways thanks and yeah cool video cheers!!!

[@tbrindan]

Got the answer for this in another one of your video. Cool stuff. Cheers again !!!

[@EbikeSchool]

The BMS should be rated for at least the number of amps that the controller will pull, but preferably more. So a 26A BMS would work in this case, but a 40A BMS would be better, since it would be extra strong and not be pushed to its limit like a 26A BMS would be.

[@how27udo]

What about if your controller is more powerful than your batteries. Can a BMS system help or rather, can you limit your controller settings to reduce the current/load?

[@truth.speaker]

3:23 "because no cell is ever better than another cell". Haven't tried the 1 dollar specials eh? ;-)

[@tedhancock68]

Well the * next to that statement would be if you don't get lied to. For example I bought Samsung modem batteries that have only 2200mah capacity and 0.5A continuous discharge. Crappy batteries right? But at 0.45 USD each, they are a great choice for the inexpensive low drain applications I sometimes build. The key is that nobody told me they were 9000mah and charged me 4 USD each for cells that are actually 600mah.

[@truth.speaker]

@@tedhancock68 k

[@George-Madalin]

Hello.i order a electric bike wheel (1000w 48v) and at description says that i need to use a battery no less then 17Ah.i have to use a 13series and 4parallel?

[@justinfoster6135]

Hey mikey I'm new to your channel and have learned a lot and I have a question if I wire two 18650 batteries in series would I have to double the charging voltage and current

[@gullivergimeno1520]

Hi, I would to buy ebike is there any restrictions on the speed or wattage required by law to be legal?

[@dfswhip]

another informative video, great work, could a front hub generator be connected to controller/bms and trickle charge your battery, for long rides/touring, would it be worth it?.

[@mamadkhalid]

Good video, thank you.I have one question please for my e bike: I use charger lead acid with same voltage and amperage, no risque for Battery ? Easy motion bike

[@EbikeSchool]

Do you mean a lead acid charger for your lithium battery? Generally that's not a good method. A proper BMS can help protect the battery from a mismatched charger, but it's generally not a risk you'd want to take. There are a number of inexpensive lithium battery chargers out there: evfittinggreentime.aliexpress.com/store/group/Lithium-Lipo-LiFePO4-Charger/313864_210769759.html?spm=2114.12010608.0.0.E6AJ6e&aff_platform=link-c-tool&cpt=1494931216088&sk=BeeyrRz&aff_trace_key=d7f4cbc466eb416c89d7b8ed4ee1c249-1494931216088-08222-BeeyrRz

[@mamadkhalid]

Voltage 36v 2a same foto : goo.gl/images/nKpkNx

[@EbikeSchool]

Generally a 10s 36V lithium battery needs a 42.0V charger, as each cell gets charged to 4.2V and there are 10 cells in series, giving 42.0V total from the charger.

[@matthewmaniace817]

I have a question I just can’t figure out the math lol I build a 20s10p 72v battery using NCR18650bd cells trying to figure out the amp hours also discharge amperage is there any way I could get some help I also built a20s8p with same cells I actually built this for a KTM conversion to electric with QS165 with FarDriver ND72680 controller I would really appreciate any type of help thank you

[@jbranalsaied6093]

Hi how can I 36v 2Ah Battery from old Loptop’s Battery? Thank you for your very important information

[@alireza071]

Hi want to build 72v battry pack with 100a continuous discharge can u advice what cell is best to use pls

[@FutureWiredTec]

Hey guys, A question... :) I have a 500w ebike motor rated for 36V and a 500w controller. My battery (currently) is 10AH 36V which started to shut down on high load scenarios and was "fixed" by warranty (my bet is that 500w was torturing the battery for continuous current higher than designed). although the battery was "fixed" (seems really like they disabled the bms, since there are serious voltage drops still) I'm looking for a battery to unlock the full potential of the 500w motor. So I'm thinking to buy these cells connectors ( and 18650 cells) and really make just my own battery but I'm not sure at what current rating(with a bms), 15AH is enough for 500w ebike, what should i target? And my current battery as far as i understand can deliver upto 360 watts of power, is that correct? (36V * 10Ah = 360W )?

[@thediscoman2001]

i have a question if you extend to say 5 sets of cells or 6 sets of cells with the same configuration surel that should be enough, i have 65 sanyo 18650 batteris and have a 1000watt motor how many batteries in series would i need to use with this the motor requires a 48 volt battery, i did not know this at the time as i had a 38 volt batterie aND IT WOULD NOT WORK ON THIS MOTOR

[@johnson12379]

I wonder which is better between the two, a 20ah 48volts of Sony or of Panasonic

[@kunalpawar278]

Hello, First of all thanks for the video, well explained. My question is on cell chemistry in the battery pack ? Like how much percentage of cobalt, Nickel, Manganese or cadmium is used in cell chemistry. And which is the best electrochemistry according to you in terms of best pack output? Is cobalt is going to use less or obsolete in near future. Thanks,Kunal

[@adelgc]

Hi yours videos are very amazing , so, i didn't understand why you prefer aliexpress as source of BMS since the majority of end of charge control is 2.5V .for some batteries are good but the samsung 26f 2600mah have :2.75v cut of voltage...and for other batteries . other thing , why connect a fine positive cable from bms to battery pack and thick cable from battery to engine (do you think that difference of thickness of positive wire are normal ?) . can you explain this note by a new video . thanks.

[@czarzenana5125]

Cable-thickness required is (only) depending on the current running through that cable. The motor can draw high currents, so you need thick cable. The BMS has 2 main leads to the battery pack that must be as thick as those running to the engine. The other leads are just measuring leads which draw little current. If they measure a problematic situation the main leads are disconnected by the BMS. I agree 2.5V is too low for many batteries and why should you go down to 2.5V? Between 2.8V and 2.5V the battery does add very little capacity, so it's better to be on the safe side.

[@abderrahimtagangout8487]

Hi, many thanks for your videos. i have a question, i build my own pack, 11,2Ah, 36V connected to 350w Hub motor, the motor can be powered from 36V to 48V. i use a cheap controller from china 20$, and he can handle till 350w My Battery-Power go down after driving 16km. my Question, do i have a wrong dimonsioned Battery-Pack? i use INR18650 29E Many thanks

[@davemisunas6385]

Would like to see a video explaining how to trouble shoot a battery pack... find bad cell or ?

[@harishsanu2457]

Hi... Can you please give clear explanation about call pack combination like 1S2P and so on

[@pavlossoultoukis4448]

nice video keep up the good wark you healped me allot to finish my e bike.

[@sailing7seas]

OK, gotta make sure I'm not screwing up. I'm ordering a Bafang BBo2 750 watt 48v mid drive Planning on building a 5p 14s battery using 18650B 3.7 3500ah samsung

[@singh2695]

Hi I have 48v 1500w 45a controller for this system how many amps I need and which cells I can use thanks

[@al682417]

is there a more current version of this- has battery tech changed much since this vid was made?

[@kaylor87]

Okay, I am losing my mind right now... About a year or so ago, I was working on an 18650 project, and somewhere, somehow I found this really nice comparison website someone had created. I can't remember at all what it was called, but it was a really great tool where you could sort and filter a ton of different lithium battery options by type, capacity, cost, brand, size, weight, etc..., tons of different specs to sort with, and it would tell you who is selling them for the best price. It was a live tracker of some sort, and a tool people would use to find the best prices on bulk batteries. Does this ring any bells to anyone? Might someone know of the website I'm talking about?? Thanks in advance!

[@catherinecedolin3683]

Looking at modern ebikes with the battery on the frame how easy are they to change the battery's in side for higher capacity ones. The reason for asking is I mountain bike and want a mid motor modern bike but they mostly come with 500 watt hours and when the bike is out of warranty ie buying a used e bike I was thinking of upping this by changing the batteries to higher capacity ones but same amount of batteries thanks danny

[@cruiser97eric1]

Yes, since all 18650 cells are the same size, you could replace the 18650 cells in the factory pack with ones having a higher ah rating. For example, if the factory cells are 2000mah, you could go to 3000mah ones to get 50% more capacity in the same space.

[@alanjagroop1282]

Can you convert 18650 battery into C BATTERIES. LIKE A CONVERTER. SIMILAR TO WRAPING CARDBOARD OR WATEVER MATERIAL AROUND THE DOUBLE AA'S TO MAKE THE BATTERY LARGER TO FIT IN THE SLOT. COULD THAT BE DONE WITH RECHARGABLE 18650 BATTERIES

[@cruzazulonlineful]

HI Micah,I have a FalconEV 1000wat 48volt kit for an electric bike. Also I have 52 Samsung 26F that I want to make 13S4P as per your calculations I have 20 amp output, but my controller is a 45Amp controller. What can I do to limit the demand of the controller? Can I limit the throttle somehow? Thanks!

[@EbikeSchool]

Search ebike controller shunt modification. If your shunt has two bars, you can snip one to cut the current in half. If it has three bars, you can snip one to reduce the current by 1/3. You can also use a cycle analyst to control the current, but it's a bit more expensive.

[@cruzazulonlineful]

Thanks!!!

[@dalejohnson2123]

How do I send a private message to receive your book on building a battery pack for an e bike?

[@SilverClouds2]

Question? Can I use Super Capicator like Maxwell along with 36v ebike battery for added power. I need bike to make round trip of 50 miles.

[@hardergamer]

No, look how many amps the capacitors hold then cross compear then to battery cells and you will see they hold only a very small amount of current.

[@rudinoer6934]

Thanks Micah for another good info. I have learnt a lot from watching your videos.

[@kd7alt]

I'm looking at building a battery pack for my tent trailer. I purchased a 100 amp bms for 4 call pack and a power booster to be able to charge from standard automotive power from 12 volt to 13.8 volts when engine is running. I want to stick around 75 amps to not over tax the bms at max. The idea is to get away from lead acid batteries which cost a lot and are heavy, and also don't last but 2 years on average in a RV. let me know your thoughts.

[@benji376]

kd7alt i did the exact same thing! Thought i was the only one...

[@benji376]

Wait, no. What I did was to purchase multiple 12v (3s 100A battery bms'es) so that i can connect all of them in parallel to charge them at 12v. When I'm using it in my bike, i put on a homemade adapter that puts all the batteries in series so that i get the (in my case 62volts)

[@a-aron2276]

kd7alt hey hows it going. if you're using it for the trailer tent first thing you need is that step up converter to 16.8v as thats the full charge voltage, the other problem is that lithium batteries need a two stage charge. the constant current and constant voltage stages. so to be honest I'd recommend just buying a fast charger with a 3phase plug adapter (i can't think of the name but they have that blue lid) or the other easy way out is if you want the car to do the charge attach an inverter to get 110v/220v and plug in that charger then into the inverter. I've no idea if that helps but i hope so.

[@lbenegas]

Does the color of the cell indicate anything? Or it is just estethics?

[@JohnSmith-js7gn]

Hey, Great Video, My battery pack on my scooter is 14"x 4" and 36V 10.4 Ah , So what should I do on my case , would you please explain that. Thank you ..

[@czarzenana5125]

A 18650 battery is 18mm in diameter and 65mm long, hence the name 18650. For 36V you should put 10 in series and use as many series in parallel as you can fit. Do not forget you also need room for the BMS and cables. If my math is alright you should be able to fit up to ten series of 10 batteries (assuming your battery-pack is cylindrical). That 100 batteries would give you up to 35 Ah. You could also use less series. 6 series would need 60 batteries and give up to 21 Ah depending on the batteries used.

[@JorgeFlores-ck8bp]

MMm I got some questions, like how do I know what is the right controller for my bike ??? Lets assume than I want hi speed like 120 km per hour and I also want to be able to keep that speed for 1 hour is that possible ? Does my weight affects the equation ? How do I know what motor to buy??? If you can send me the book that would be great!

[@GauravSharma-tq7ry]

Sir please help i have facing a problem .. i made a LFP 12.8v 30Ah battery pack .. and after 3month found one series of battery (5cells of 6ah) all dead .. what kind of problem is this.. how can I resolve this please tell me

[@nadeemuk6194]

Hi brother please my laptop has ICR 18650 22f DMEGC INR18650-26E 18650 can I use them in my laptop please reply me as soon as possible thanks.

[@eskilr]

hi can you make a video where you show how to find the capacity of a cell? i mean with discharging IT an stuff

[@EbikeSchool]

That's a good suggestion. I'll try to work that one in. I've got a few other requests I'm already working on for the next few videos.

[@anacarolinasanches8896]

Hi Micah, Thanks for all the tips! you are great! I found some 18650 Ultrafire batteries with 9800mAh. Do you know those kind of batteries? Do you think it Is any possible to have so much amps in each cell? I found very hard to believe in it, since the best batteries are between 2.5 and 3 Ah, but I thought if this is true it would be amazing, isn't?

[@EbikeSchool]

Haha, yea those 9800 mAh are nowhere near realistic. The highest 18650s are 3500 mAh and you can bet they are much more expensive than the 9800 mAh ones...

[@anacarolinasanches8896]

thank you so much :))

[@EbikeSchool]

vruzend.com/product/set-of-2-lg-mj1-18650-battery-cells/

[@czarzenana5125]

People in Europe can go to eu.nkon.nl

[@dhanasekarr8215]

Please explain types of lithium ion battery, which one is more efficient for ebikes

[@extremerodsdrag4683]

Dear where can buy the Samsung or LG cells like 165pcs ????????

[@thepianokid27]

Hi Mikey, I have seen lithium ion battery packs being sold online, same spec 48V packs, with the only difference being one is for motors 750W or lesser, while the other is 1200W or lesser. How do u determine whether a battery pack is suitable to power a certain motor of a certain wattage rating? Thanks for answering!

[@bFlattheOriginal]

It depends on the amps your controller can pull. Amp-hours (ah) is just the capacity of the cells (think of them as the size of your "gas" tank), but what counts is matching the amps the controller can pull to the continuous amps the battery can provide. If the 1200w motor needs 30 amps, and one of those battery packs can only deliver 20 amps, it's not the right one for the more powerful motor.

[@thepianokid27]

I see. So am I right to say that the controller basically determines how much power your ride will get regardless of the battery? Like in your above example, if the 1200W motor needs 30 amps, but the battery is capable of delivering 40 amps, the controller would just draw 30a correct? But what if the battery is a 60V and is capable of delivering 20 amps, would that battery then be capable of delivering the 1200W the motor requires, assuming the controller is able to draw that amount of amps?

[@bFlattheOriginal]

Q1: correct. Q2: Watch Micah's other videos on Two-Motor 2WD, Overvolting for More Speed, and How to Properly Choose an Ebike Battery. Heck, watch them all!

[@thepianokid27]

Ok i will :) Thanks again! Appreciate the battery build vids you churn out!

[@czarzenana5125]

1. Correct 2. If you increase the voltage, the motor will draw a higher current and you will need a BMS that can handle that higher voltage and current. Increasing the voltage is limited by the build-quality of the motor. Higher currents can burn the coils of the motor. It is better to chose a suitable motor.

[@ATARI-DAVE-73]

Hi, so what I'm getting from this is if I'm planing on making a 52v 1500w 35ah 30 amp pack or something around that size, should go the 5 amp cells over the 10 amp cells. I was looking at lg mj1. Would 10 amps be to much or does the bms sort this out ? It's to run a bafang 1000w mid.........

[@czarzenana5125]

The INR18650-MJ1 nowadays is rated 10A. The older version was rated 6.7A if I am not mistaken. The higher the amperage of the battery, the better your choice. Higher amp cells are normally more expensive though, so you should not overdo it with cost in mind. 35 Ah would mean you put 10 series of batteries in parallel. 52V means you put 14 batteries in series. So you would need 140 batteries to accomplish that. Each battery would draw 30/10= 3 Amps. For safety reasons I would double that to be the minimal current of the battery (so at least 6A batteries). Easy to understand: the more batteries are paralleled the less current each battery will draw.

[@nassalavi6146]

Hi dude. First of all thanks for all of your videos. You have put together 5 part videos explaining in details, how to build a battery pack, But looks like I am electronically challenged (I think me being autistic has something to do with it)because I can’t get my head around which cell to use and how to connect the battery together to achieve a light weight 52v 17.5ah battery for a TSDZ2 48v 250w motor. I am going to change the program to Flexible OpenSource firmware. More I research more confuse I get🤯. any chance you can help me with which battery cells and a drawing of how to Connect theme? Practically I am very good!! Thanks man!!!

[@ppsprawit1953]

Thanks​ for​ open​ my​ thinking.

[@saishraddhatours]

I am planning for 200km range with 500W hub motor bike. Bike gross weight is 25kg n my weight is 70kg Need Max Speed of 50kmph Please suggest suitable cell for battery pack

[@666skyshadow]

Could you run say a 2.9A max current battery with a 4.2A max current battery in series for 7.2A total max current?

[@cruiser97eric1]

No. If you draw 7.2A from that configuration both batteries will be operating above their maximum rating. If you draw 4.2A one battery will be above its maximum rating and the other one will not. If you draw 2.9A both batteries will be within their maximum rating.

[@666skyshadow]

cruiser97eric1 I means in parallel. Sorry.

[@cruiser97eric1]

What happens in parallel depends on how the two cells share the current among themselves. Let say initially the current is split evenly in half, 7.2A / 2 = 3.6A each cell. Then one cell is above its maximum rating and the other one isn't.

[@666skyshadow]

cruiser97eric1 since current is a measure of resistance, wouldn't the higher rated battery take the extra load once the lower rated one hits top resistance? Kind of the same principal of charging in parallel..?

[@cruiser97eric1]

The current sharing will depend on the internal resistance and on the nominal voltage for each cell. Some types of cell like to spend most of their discharging time around 3.7V and others around 3.6V. The internal resistance changes as the cells discharge and as they age. It is hard to predict which cell will have the lower internal resistance at any given time. Say for example the cell with the higher max discharge current has a lower capacity than the other one (because it is a power cell instead of an energy one). At the beginning it might have lower internal resistance and provide most of the current, but as it discharges faster, at some point the other cell might end up providing most of the current. To keep things simple and have predictable results it is best to use cells from the same manufacturer, with the same part number and same age when connecting them in parallel.

[@emaayan]

umm didn't we say that pf should actually be regarded as 5a? , you didn't mention that the closer you get for max discharge you decrease the battery capacity? , also what's the relation between c ratings and max continuous discharge rating? one last question (it propped up on esfb) is it possible to tell cell grade (a,b,c) from the cell itself? maybe from qr barcode? and something a little different, i've started to hear about 20700 cells, is that a new standard emerging?

[@EbikeSchool]

Basically all cell manufacturers rate their cells at their absolute limit - meaning the cells perform much better when used below their rated limits. C rating is just a way to measure current, where 1 C equals the capacity of the cell. So for a 3 AH cell rated for 3C max discharge, it can support a 9A max discharge. Discovering the grades of cells is largely a mystery to me. Most cells don't have it listed on them, and the grading scheme is proprietary so many manufacturers keep it secret how they make their cuts. I've never tried scanning the QR code actually, but that'd be interesting. 20700 and 21700 cells have been around for a few years but were very rare. Tesla has embraced the 21700 form factor so we'll be seeing that become much more popular in the coming years.

[@risuhu8590]

I WANT 12 V 3A FROM ZINC CHLORIDE D SIZE CELL I DONT KNOW CAPACITY OF CELL AS MANUFACTERE DOES NOT PROVIDED . IN SHORT 8 - 9 CELL CAN THIS PACK OF D CELL PROVIDE 3A CONTINOUS? I WILL USE IT IN ACTIVE SPEAKER 12 INCH POWERED BY TPA3112 BOARD 12 V --24 V

[@rdkuless]

How about the 18650 vs the Sanyo NCR18650GA cells with 3500mah per cell.

[@czarzenana5125]

The Sanyo NCR18650GA are rated 3350 mAh and 10A. You can use them, but where I live they are quite expensive compared to others. If I had to buy the batteries, I would also consider the cost per mAh. If weight is your main concern, you should use batteries with the highest capacity. What about the INR18650-MJ1 of LG? They are 3500 mAh and 10A. Today the 2900-3000 mAh batteries are more cost effective though, but that might change over time.

[@abjamali7929]

Hello sir Can you please tell what is the meaning of inr18650 25e what is tbe meaning of prefix inr and suffix 25e..?

[@saygnileri1571]

Great one thanks very much. I am wondering why different lithium cells have different mAh? Why don't they have a standart? For instance, they can be either 2600, 3000mAh, 3400mAh, 3500mAh, 4000 or even 8800mAh. (On aliexpress, very confused) Based on this, ı am searching the most cost effective lithium cells from aliexpress but they are way expensive than buying a built battery pack. I have to make big math to optimize the most effective purchase on buying 18650 cells. Can you make a categorization for different cells based on different power needs,? Please

[@davestennes305]

It mostly has to do with the composition of the anode and cathode. The composition creates resistance and capacity differences - they look to be inversely proportional, ie. when resistance is higher (higher amps), capacity (ah) decreases and visa versa - this has some good info batteryuniversity.com/learn/archive/the_high_power_lithium_ion. I would only consider brand name batteries for safety and reliability reasons.

[@saygnileri1571]

Dave Stennes thank you very much for your answer :)

[@ismailozcelik1662]

how many years does the system go cycle?

[@0ssaa]

hello. I have e-bike Greyborg, 72V 42Ah battery with 300pcs Panasonic 18650 PF cells, with 6kw cromotor. Question is, what to do with battery trought winter days? How to store it? Luckily, this winter was good and i ride my bike in winter days to discarge and charge battery. But what with people who cant use battery for some longer time? PS: you can check video about my bike on my small chanell

[@greg23842384]

0ssaa just discharge them to 3.5volts per cell for long storage

[@banitoful]

I am starting to be scooter batteries but I have no idea how to calculate the amperage of each cell for example I have a 72v 8p 20s battery I have lgebmh11865 batteries but I don't know how to know how much amperage it would have for all those batteries how to know each amperage of each cell and multiply by all to find the amperage

[@kameleont.6509]

how would you calculate using a mixture of different cells to achieve the same goal and would it affect your battery pack a great deal or would using more cells be best?

[@LeeMooEez]

Never ever mix them..this is well known taboo

[@davidk5677]

I got a question for you and I'm not sure if I can ask it here or email you but it's about stabilizing the voltage on a battery pack. P.s I picked up your book and it's very helpful for me the beginner in learning how to setup everything up and how things work 🖒🖒