tomjasz
1 GW
Sometimes I really miss Usenet and the good old fashioned, PLONK.
HK Lipo Bricks - what do I choose and why?
- Thread starter macribs
- Start date
ElectricGod
10 MW
To those who actually gave battery advice...thanks so much!
To the rest of you...say what you want, believe what you want...frankly I don't care what you think of me. I was and am looking for opinions on decent LIPO solutions and got flamed for asking so impute whatever BS you want! you are acting like a bunch of little purile children! All I can say is go let mommy hug you better!
SO how about we talk about batteries!!! As everyone knows, lots of batteries are advertised as X amp/hours at Y C rating. Reality is often times significantly less than the advertised specs. I always assume low. That's just the EE in me coming out. There is no such thing as the ideal world. Everything has losses and variance from the ideal. I'm looking for what people think are reliable LIPO packs that have LOW failure rates. I refuse to buy from Hobby King. Their reseller ratings are so bad it's ridiculous and I have had my own recent bad experiences with them. Pretty much Hobby King sucks in just about every way possible except price...assuming you can actually get them to ship to you! Fortunately batteries can be purchased elsewhere too so I am open to options. I ask because I don't know everything and have no expectations that I will ever know 1% of everything about batteries...never mind everything else.
Regarding speed controllers and BMS options. I like the Adapto options. The are really well integrated and Adapto products are obviously developed for the EV experimenter and builder in mind. Sometimes I wish I had gone that route. I however chose a different route like many EV experimenters do. I chose to use a Kelly KBS 72221E motor controller. It had a lot of nice functions that I wanted like regen and motor detection among others. The way KBS handles reading hall sensors makes it work well for a wide variety of motors. Kelly is known for making good products and they design for the small and large EV alike.
Like most folks on here, I like building things so making my own battery packs and experimenting was going to happen no matter what. I went the onboard BMS route so that every charge was a balanced charge. THe BMS I bought wasn't so great and I am particular about how well my batteries balance charge so I don't recommend the boards I bought, but here they are (http://www.ebay.com/itm/44V-48V-50-4V-12S-30A-Lithium-ion-Li-ion-LiPo-Li-Polymer-Battery-BMS-PCB-System-/221274094989?hash=item3384f6bd8d:g:30UAAOxy-NVSEdSO). They work...mostly...but as many know charging LIPO's to 4.2 volts gives you fewer charge cycles than does charging to say 4.15 volts. These BMS boards charge to 4.2 volts or a little over. Next time I will go with BestTech BMS products (that is if I don't find another option I like more). Suggestions are welcome! I think a stand alone BMS that included an LCD, measured watts in and out, amps used, cell status, etc and perhaps some logging like Adapto has would be great, but I haven't found a real option like that despite many hours of searching both on and off of ES. I think a BMS that simply had a 3 color LED per charge channel would be great. Some kind of built in visual status is better than none. I randomly plug in a cell log as a result. Too bad they weren't designed a little better so you could leave them hooked up all the time. I would buy however many I needed to cover all my cells and integrate them into my battery packs.
To the rest of you...say what you want, believe what you want...frankly I don't care what you think of me. I was and am looking for opinions on decent LIPO solutions and got flamed for asking so impute whatever BS you want! you are acting like a bunch of little purile children! All I can say is go let mommy hug you better!
SO how about we talk about batteries!!! As everyone knows, lots of batteries are advertised as X amp/hours at Y C rating. Reality is often times significantly less than the advertised specs. I always assume low. That's just the EE in me coming out. There is no such thing as the ideal world. Everything has losses and variance from the ideal. I'm looking for what people think are reliable LIPO packs that have LOW failure rates. I refuse to buy from Hobby King. Their reseller ratings are so bad it's ridiculous and I have had my own recent bad experiences with them. Pretty much Hobby King sucks in just about every way possible except price...assuming you can actually get them to ship to you! Fortunately batteries can be purchased elsewhere too so I am open to options. I ask because I don't know everything and have no expectations that I will ever know 1% of everything about batteries...never mind everything else.
Regarding speed controllers and BMS options. I like the Adapto options. The are really well integrated and Adapto products are obviously developed for the EV experimenter and builder in mind. Sometimes I wish I had gone that route. I however chose a different route like many EV experimenters do. I chose to use a Kelly KBS 72221E motor controller. It had a lot of nice functions that I wanted like regen and motor detection among others. The way KBS handles reading hall sensors makes it work well for a wide variety of motors. Kelly is known for making good products and they design for the small and large EV alike.
Like most folks on here, I like building things so making my own battery packs and experimenting was going to happen no matter what. I went the onboard BMS route so that every charge was a balanced charge. THe BMS I bought wasn't so great and I am particular about how well my batteries balance charge so I don't recommend the boards I bought, but here they are (http://www.ebay.com/itm/44V-48V-50-4V-12S-30A-Lithium-ion-Li-ion-LiPo-Li-Polymer-Battery-BMS-PCB-System-/221274094989?hash=item3384f6bd8d:g:30UAAOxy-NVSEdSO). They work...mostly...but as many know charging LIPO's to 4.2 volts gives you fewer charge cycles than does charging to say 4.15 volts. These BMS boards charge to 4.2 volts or a little over. Next time I will go with BestTech BMS products (that is if I don't find another option I like more). Suggestions are welcome! I think a stand alone BMS that included an LCD, measured watts in and out, amps used, cell status, etc and perhaps some logging like Adapto has would be great, but I haven't found a real option like that despite many hours of searching both on and off of ES. I think a BMS that simply had a 3 color LED per charge channel would be great. Some kind of built in visual status is better than none. I randomly plug in a cell log as a result. Too bad they weren't designed a little better so you could leave them hooked up all the time. I would buy however many I needed to cover all my cells and integrate them into my battery packs.
Samd
10 MW
Don't dabble with a low voltage eBay bms. Get a bestechpower.
If you won't deal with hobby King it's your loss.
If you won't deal with hobby King it's your loss.
I have moved away from LiPo once the Samsung 25R and 30Q became available, but when I still owned LiPo...Bulk charge the pack with a Meanwell/Meanwell-clone for a fast charge each day...on the week-end when I can take the time to monitor the pack, I do a slow balance-charge once a week (or on slow months with less riding maybe twice or once a month?).
Rather than plugging one balance charger into each parallel string in succession, most buy one cheap RC balance charger for each paralleled string. This is one of the reasons 44V / 12S is popular, you buy one 120V-12V power supply, and use it to power two RC 6S chargers, with one each connected to the two 6S strings that make up the 44V pack. There are dozens of combinations, 3 X 6S = 18S, 4 X 5S = 20S.
Some of this has to do with the controller you're using. If it has 63V capacitors, then you can run as high as 14S (6S + 4S + 4S), but...if you have 100V capacitors (or upgrade to them), and also have the popular, efficient, and cool-running 75V 3077 FET, you could try 15S (3 X 5S).
A few years ago, there were very few choices for high-amp batteries, so many high performance systems went to higher voltages, with one of the design limiting factors being that there wasn't a great selection of motor sizes and Kv's available. This past year has been a milestone. There has been a proliferation of high-amp cells and the hub and non-hub motor choices. Leafbike 35H has 4 Kv's available, and the large QS has over eight Kv's (with some windings being halfway between the common windings). I am a big fan of 14S, using 18650's, and...a fairly compact 5P string of 25R's will provide 100A from a fairly small package. Recently, Luke has been posting a preference for considering lower voltages and raising the amps.
If safety is a concern, you can get a horrible high-amp burn from any voltage, but at 12S you won't get electrocuted. If you want to keep your life simple, get the large Amp-hour Multi-stars in some combination of 4S / 6S http://www.hobbyking.com/hobbyking/store/__1387__85__Batteries_Accessories-Multirotor_Lipoly.html
My experience with Turnigy and Zippy LiPo is that they are equal in performance, life cycle, and reliability (the experience of others might be different, YMMV). Luna Cycle has 18650-cell packs from the 25R, 30Q cells, reliable, safe, etc. [full disclosure: I write for electricbike.com, which is owned by the same guy as the Luna store, so don't trust anything I say], if you want the MJ1 cell to build your own pack, they can be found at Wake and Vape.
Rather than plugging one balance charger into each parallel string in succession, most buy one cheap RC balance charger for each paralleled string. This is one of the reasons 44V / 12S is popular, you buy one 120V-12V power supply, and use it to power two RC 6S chargers, with one each connected to the two 6S strings that make up the 44V pack. There are dozens of combinations, 3 X 6S = 18S, 4 X 5S = 20S.
Some of this has to do with the controller you're using. If it has 63V capacitors, then you can run as high as 14S (6S + 4S + 4S), but...if you have 100V capacitors (or upgrade to them), and also have the popular, efficient, and cool-running 75V 3077 FET, you could try 15S (3 X 5S).
A few years ago, there were very few choices for high-amp batteries, so many high performance systems went to higher voltages, with one of the design limiting factors being that there wasn't a great selection of motor sizes and Kv's available. This past year has been a milestone. There has been a proliferation of high-amp cells and the hub and non-hub motor choices. Leafbike 35H has 4 Kv's available, and the large QS has over eight Kv's (with some windings being halfway between the common windings). I am a big fan of 14S, using 18650's, and...a fairly compact 5P string of 25R's will provide 100A from a fairly small package. Recently, Luke has been posting a preference for considering lower voltages and raising the amps.
If safety is a concern, you can get a horrible high-amp burn from any voltage, but at 12S you won't get electrocuted. If you want to keep your life simple, get the large Amp-hour Multi-stars in some combination of 4S / 6S http://www.hobbyking.com/hobbyking/store/__1387__85__Batteries_Accessories-Multirotor_Lipoly.html
My experience with Turnigy and Zippy LiPo is that they are equal in performance, life cycle, and reliability (the experience of others might be different, YMMV). Luna Cycle has 18650-cell packs from the 25R, 30Q cells, reliable, safe, etc. [full disclosure: I write for electricbike.com, which is owned by the same guy as the Luna store, so don't trust anything I say], if you want the MJ1 cell to build your own pack, they can be found at Wake and Vape.
nutnspecial
10 MW
Some good points and comments I could quote but glad you rabble rousers calmed down 
I am using turnigy 5.8 and they are very reliable @ about 1/4 the c-rate. Seemed like the best c-rate and ah for the price at the time. Out of a combo of 6s and 4s, I do have 2 cells of 16 in the 4s that will need retired early. Although it's only the 4s which were bought later in the year and had lower balance consistency out of box, I'm chalking it up to newb mistakes such as pretty low pack overdischarge and also trying to draw 70a and charge @15a a single 5.8 string of 30c (so half c on draw and 3c charge). Since I've paralleled to 11.6ah. I think I will prob do the same next time as it works for my build pref. As others have noted, bulk charge most of the time, and very occasionally balance.
Electricgod, kinda a good name, maybe Luke's mad he didn't think of it? (jk )
What are you planning on doing with the 8ah cells when they come (config and pack layout)? Draw requirements? At least they'll be assumably fresh stock. If availability is holding you up could you cancel/switch to another? What would it be? Do a123 pouches work for what you want? Do you think 'sleeping tazmanian devil' is more appropriate simile for a lipo cell?
I am using turnigy 5.8 and they are very reliable @ about 1/4 the c-rate. Seemed like the best c-rate and ah for the price at the time. Out of a combo of 6s and 4s, I do have 2 cells of 16 in the 4s that will need retired early. Although it's only the 4s which were bought later in the year and had lower balance consistency out of box, I'm chalking it up to newb mistakes such as pretty low pack overdischarge and also trying to draw 70a and charge @15a a single 5.8 string of 30c (so half c on draw and 3c charge). Since I've paralleled to 11.6ah. I think I will prob do the same next time as it works for my build pref. As others have noted, bulk charge most of the time, and very occasionally balance.
Electricgod, kinda a good name, maybe Luke's mad he didn't think of it? (jk
)What are you planning on doing with the 8ah cells when they come (config and pack layout)? Draw requirements? At least they'll be assumably fresh stock. If availability is holding you up could you cancel/switch to another? What would it be? Do a123 pouches work for what you want? Do you think 'sleeping tazmanian devil' is more appropriate simile for a lipo cell?
ScooterMan101
1 MW
I would like to do the same, however the cost of a good pack is still up there , especially when there is tax on a $ 400 + pack , and $ 30-60 for shipping.
So I am still on the fence as far as a decision on either Lipo's or 18650 Pack,
For those who live out of state and do not have to pay nearly 10% in tax, a ready made 18650 pack looks like a closer price to a lipo set up.
>
>
I am also becoming a fan of the 14s ( 52volt ) pack, as I am thinking that the 48 volt controller that a person presently has on their bike/scooter, etc. can handle the slight increase in voltage, while using the existing controller.
However at the present time ..
There is a lack of 7 s packs at hobbyking, I really do not want to string too many packs together, Zippy makes a 7 s pack, but , it is only 5800mAh, so 4 is needed, and when you add the cost of them, then a 14s
packs made from 18650 looks like an easier way to get into 52 volts. I am not finding Turnigy or Multistar 7 s packs.
So that leaves a ready made 14s pack from a place like Luna, however the good shaped pack ( the Shark Pack Housing ) it looks to me to be only 4 p, when you said , and I also feel , that 5 s would be better. both for range and higher continuous amp draw.
>
>
Since you in a way work for Luna, Please tell the owners of Luna Cycle LLC. the importance of having a charger that will charge on more than 1 set voltage,
Look at the charger that I would like to buy from them , the Blue Case, $ 99 charger.
it
is only available in 48volt , or , 52 volt. Meaning a person would have to buy Two of them when using different packs and/or different bikes .
I have a couple of 48 volt packs presently, but want to go ( meaning Buy from someone ) a 52 volt pack in the future, add to that I want to be able to charge my scooter 36 volt system in the future as well, Meaning I will also need to buy a 36 volt pack as well .
A company that sells a $ 50- $ 100 charger with two amp output settings, and , with a different voltage dial to be able to charge the different packs will be the Winner !
( the $ 300 charger from Grin is over budget for me and others, it is big to big for me to carry around and probably too complicated for me to use )
, a simple dial or switch for different amps and volts is better for most people. Keep it simple with Switch for the different amp output, and use a Dial for different voltage outputs !
You write for electricbike.com, an article about the need for the charger I describe above, ( Multi Voltage / Amp charge rates, simple to use, small to take to the Office, etc. ) is needed.
Thank You
>
So I am still on the fence as far as a decision on either Lipo's or 18650 Pack,
For those who live out of state and do not have to pay nearly 10% in tax, a ready made 18650 pack looks like a closer price to a lipo set up.
>
>
I am also becoming a fan of the 14s ( 52volt ) pack, as I am thinking that the 48 volt controller that a person presently has on their bike/scooter, etc. can handle the slight increase in voltage, while using the existing controller.
However at the present time ..
There is a lack of 7 s packs at hobbyking, I really do not want to string too many packs together, Zippy makes a 7 s pack, but , it is only 5800mAh, so 4 is needed, and when you add the cost of them, then a 14s
packs made from 18650 looks like an easier way to get into 52 volts. I am not finding Turnigy or Multistar 7 s packs.
So that leaves a ready made 14s pack from a place like Luna, however the good shaped pack ( the Shark Pack Housing ) it looks to me to be only 4 p, when you said , and I also feel , that 5 s would be better. both for range and higher continuous amp draw.
>
>
Since you in a way work for Luna, Please tell the owners of Luna Cycle LLC. the importance of having a charger that will charge on more than 1 set voltage,
Look at the charger that I would like to buy from them , the Blue Case, $ 99 charger.
it
is only available in 48volt , or , 52 volt. Meaning a person would have to buy Two of them when using different packs and/or different bikes .
I have a couple of 48 volt packs presently, but want to go ( meaning Buy from someone ) a 52 volt pack in the future, add to that I want to be able to charge my scooter 36 volt system in the future as well, Meaning I will also need to buy a 36 volt pack as well .
A company that sells a $ 50- $ 100 charger with two amp output settings, and , with a different voltage dial to be able to charge the different packs will be the Winner !
( the $ 300 charger from Grin is over budget for me and others, it is big to big for me to carry around and probably too complicated for me to use )
, a simple dial or switch for different amps and volts is better for most people. Keep it simple with Switch for the different amp output, and use a Dial for different voltage outputs !
You write for electricbike.com, an article about the need for the charger I describe above, ( Multi Voltage / Amp charge rates, simple to use, small to take to the Office, etc. ) is needed.
Thank You
>
spinningmagnets said:
tomjasz
1 GW
I'm a broke stroke recovery guy and I can manage the Satiator. To develop a charger that does multiple voltage packs and has the setting you want is an expensive process. It's a Satiator! While some think development is a cake walk, please try and develop such a beast. It's not going to happen for $100 or even $200. If it were possible we already be able to buy them, from my view.
I found the Satiator has the added benefit of any percentage of charge. If Grin's dat is HALF correct the $300 charger will pay for itself in the life extension of one pack. The luna charger can charge at 80 and 90% too. There are now Luna 36, 48, 52, and 72V models. But if you're planning on having 3 or 4 voltages of packs the aviator suddenly is a greet deal. Especially when you factor in the life extension.
I bought 3 and sold two. The best buy in my eBike adventure. Yup it stung on my retirees pension, but when I review all the advantages, I'm happy i skipped a score of tavern trips in favor of a $300 charger. Less vodka and a truly remarkable charger. It's quite small and designed to mount on a bike too! Being completely water resistant.
As always, YMMV
I found the Satiator has the added benefit of any percentage of charge. If Grin's dat is HALF correct the $300 charger will pay for itself in the life extension of one pack. The luna charger can charge at 80 and 90% too. There are now Luna 36, 48, 52, and 72V models. But if you're planning on having 3 or 4 voltages of packs the aviator suddenly is a greet deal. Especially when you factor in the life extension.
I bought 3 and sold two. The best buy in my eBike adventure. Yup it stung on my retirees pension, but when I review all the advantages, I'm happy i skipped a score of tavern trips in favor of a $300 charger. Less vodka and a truly remarkable charger. It's quite small and designed to mount on a bike too! Being completely water resistant.
As always, YMMV
I work for Eric as a writer, but Eric does what he wants. The choice to have 2A and 5A charging, plus charge to 80%, 90%, 100 % were choices that were thoughtfully made. Eric insisted that his chargers would have only one voltage, and would be made from a reputable manufacturer, and would sell for $99.
I think those were good choices, but I had no input. Variable voltage costs a lot more, and not enough customers were willing to pay a higher price for a variable voltage unit, now that the very nice Satiator is available. So, Luna chargers are not likely to come out with variable voltage as a feature.
I think those were good choices, but I had no input. Variable voltage costs a lot more, and not enough customers were willing to pay a higher price for a variable voltage unit, now that the very nice Satiator is available. So, Luna chargers are not likely to come out with variable voltage as a feature.
ElectricGod
10 MW
nutspecial said:Some good points and comments I could quote but glad you rabble rousers calmed down
I am using turnigy 5.8 and they are very reliable @ about 1/4 the c-rate. Seemed like the best c-rate and ah for the price at the time. Out of a combo of 6s and 4s, I do have 2 cells of 16 in the 4s that will need retired early. Although it's only the 4s which were bought later in the year and had lower balance consistency out of box, I'm chalking it up to newb mistakes such as pretty low pack overdischarge and also trying to draw 70a and charge @15a a single 5.8 string of 30c (so half c on draw and 3c charge). Since I've paralleled to 11.6ah. I think I will prob do the same next time as it works for my build pref. As others have noted, bulk charge most of the time, and occasionally balance.
Electricgod, kinda a good name, maybe Luke's mad he didn't think of it? (jk
What are you planning on doing with the 8ah cells when they come (config and pack layout)? Draw requirements? At least they'll be assumably fresh stock. If availability is holding you up could you cancel/switch to another? What would it be? Do a123 pouches work for what you want? Do you think 'sleeping tazmanian devil' is more appropriate simile for a lipo cell?
Thanks for the input about turnigy packs. I try to read a lot so that I can learn from others mistakes and hopefully make fewer of them myself. I just finished building a new charger that outputs 50.4 volts (yawn! I know I know...I'll eventually get up to 72 volts later) so balancing randomly is a useful way to go and I wont need a BMS anymore. My old charger put our 56 volts. I couldn't not use a BMS on my packs. I may just not do BMS's anymore since it's not a critical component now. And my Kelly has a settable shut off voltage that I trust. My old chinese crap controller was not reliable in that regard.
ElectricGod...when I was thinking of a name for ES, I thought what would I think was clever and maybe a little pretentious...and to my surprise...it was available. The rest is history.
New batteries and configuration...
I want to go to 72 volts. I had 4 6S 8000mah packs on order with HK, but they screwed around for over a month and never shipped and never had any info about when they would have stock so I finally canceled the order. I'll buy elsewhere and probably never use HK again. With 8000mah at 1C by 4 wide that gives me about 24 amps. I can easily do 23-25 mph at 24 amps. Obviously I will run at higher than 1C quite often. So my thought was to maximize pack life and have good capacity, that I would run 4 packs in parallel. When I say "pack" I mean 4 individual strings of 20 cells or in the case of R/C packs, that would be 3 6S and 1 2S packs in series to get me to 20S. I have noticed that price per cell is lowest for the exact same cells in a 6S pack than for smaller packs. Also, most LIPO chargers now days do 6S so it's a good all around R/C pack size choice. My Kelly controller maxes out at 90 volts so that's essentially 21S. A little margin for error is always good so I'll go 20S or 84 volts. This is the battery bay in my scooter as it is configured today. I have a little expansion room, but I would prefer to NOT choke out the KBS if possible...even though it is mounted with heat sink compound to the metal box.
I built this platform over the back wheel. It will hold my 240 pounds so using it as an auxiliary battery box will not be a problem. Pretty much as long as there is money in the bank, I can add batteries for whatever capacity I can imagine. Space is not an issue on this project.
macribs
10 MW
- Joined
- Jul 22, 2014
- Messages
- 3,702
Me I would have chosen Electric Cod
A little strapped for cash these days. I might need to go the Lipo still. I was gonna do a 18650 pack myself but I got a chance to unload all them 18650's at a mark up and that saved Christmas
If I can find room for both 18650's again and a spot welder - or the new wonder metallic glue if that comes available I might still choose 18650. If not cheap 5Kmah 4s hard packs. Often they are on sale too I've noticed.
A little strapped for cash these days. I might need to go the Lipo still. I was gonna do a 18650 pack myself but I got a chance to unload all them 18650's at a mark up and that saved Christmas
If I can find room for both 18650's again and a spot welder - or the new wonder metallic glue if that comes available I might still choose 18650. If not cheap 5Kmah 4s hard packs. Often they are on sale too I've noticed.
nutnspecial
10 MW
That's cool macribs. . . would love to see your build sometime. Did I miss it?
e-god, hopefully abbrev are cool with you occasionally? I'm wondering how many cells are pictured there?
(Nice ride btw!)
Something like 14s 4p? And you want 20s 4p? Yes, if I can safely get 70a from my 20s 2p 5.8 30c you can def get 24a++ outa 20s4p 8.0 10c. Safely that would be 80a @ 1/4c. Lots of range. Very low draw on battery. Could handle a 30a bulkcharger. . . . What about increased speed from 20s voltage though? Room for 80cells?
If not buying hk where else is there? What about a123 prismatic pouch I hear about?
e-god, hopefully abbrev are cool with you occasionally? I'm wondering how many cells are pictured there?
(Nice ride btw!)
Something like 14s 4p? And you want 20s 4p? Yes, if I can safely get 70a from my 20s 2p 5.8 30c you can def get 24a++ outa 20s4p 8.0 10c. Safely that would be 80a @ 1/4c. Lots of range. Very low draw on battery. Could handle a 30a bulkcharger. . . . What about increased speed from 20s voltage though? Room for 80cells?
If not buying hk where else is there? What about a123 prismatic pouch I hear about?
macribs
10 MW
- Joined
- Jul 22, 2014
- Messages
- 3,702
No you didn't miss it, it is still very much in production :lol:
I am a year behind schedule on this build, real life and all you know. I was down to just missing the controller, then I got a chance to earn a few $ on the 18650 cells and it was just too good to pass up just before Christmas. Yeah I know. I blew the wad on stupid Christmas presents and great food. Lame but thats life. Hopefully I will be riding by spring, everything dialed in and working. If not there is always fall, winter or next summer.
I am a year behind schedule on this build, real life and all you know. I was down to just missing the controller, then I got a chance to earn a few $ on the 18650 cells and it was just too good to pass up just before Christmas. Yeah I know. I blew the wad on stupid Christmas presents and great food. Lame but thats life.
Hopefully I will be riding by spring, everything dialed in and working. If not there is always fall, winter or next summer.
ElectricGod
10 MW
nutspecial said:
LOL! yeah e-god works. haahaha...
Those are 12s packs of 8000mah 3C LIPOs. They are still working pretty well, but 3C is pathetic. I haven't ever used them over about 2C per pack. I have my Kelly limited to 60 amps because of the LIPOs. The rest of the system can do 200+ amps and the controller can do 260 amps max or 130 amps continuous. I want to use that capacity, but my batteries aren't up to it. When I stripped out the factory wiring on this thing, I decided I didn't want to ever rewire again so I built it like my best EV wet dream.
nutnspecial
10 MW
Well based on a huge speed increase going to 20s and the limited space to increase battery by 40%, I'm thinking 20s 3p might be an issue.
I'd not heard of 3c, although that would be a good place to run the multistar 10c packs. If you're happy with speed perhaps fresh packs of 12-14s 10c with 4th parallel will work, or 3p of their 16ah packs? I'd personally love to try the 50-70c stuff, but besides the expense it's an obvious risk they'd be that much more volatile/incendiary and be more sensitive to aging
PS/ Kudos macribs, there's nothing like methodical patience (i'm told ) and you've built an impressive knowledge base.
I'd not heard of 3c, although that would be a good place to run the multistar 10c packs. If you're happy with speed perhaps fresh packs of 12-14s 10c with 4th parallel will work, or 3p of their 16ah packs? I'd personally love to try the 50-70c stuff, but besides the expense it's an obvious risk they'd be that much more volatile/incendiary and be more sensitive to aging
PS/ Kudos macribs, there's nothing like methodical patience (i'm told
) and you've built an impressive knowledge base.
ElectricGod
10 MW
nutspecial said:Well based on a huge speed increase going to 20s and the limited space to increase battery by 40%, I'm thinking 20s 3p might be an issue.
I'd not heard of 3c, although that would be a good place to run the multistar 10c packs. If you're happy with speed perhaps fresh packs of 12-14s 10c with 4th parallel will work, or 3p of their 16ah packs? I'd personally love to try the 50-70c stuff, but besides the expense it's an obvious risk they'd be that much more volatile/incendiary and be more sensitive to aging
PS/ Kudos macribs, there's nothing like methodical patience (i'm told
Yes the battery compartment wont hold more cells in my current configuration. I am considering making a single pack rather than 4 individual packs. I'm unsure how much space I will save, but it might be enough. Worst case I'll use that platform on the back wheel.
athletic91
100 W
In case anyone needs a buddy code for turning 5s 5000 20c bricks
http://www.hobbyking.com/buddy.asp?code=6B3A79A5-B2DE-4E0B-B023-325282106569
http://www.hobbyking.com/buddy.asp?code=6B3A79A5-B2DE-4E0B-B023-325282106569
macribs
10 MW
- Joined
- Jul 22, 2014
- Messages
- 3,702
I am sure it has been up over and over, but I was trying to see the C rate on 18650 compared to Lipo.
Lipo has discharge rate given in C value. Most 18650 batteries in A. Ie LG HE 2 is 20 A continuous and 30 A peak according to some websites.
How do I compare the discharge between those? To make things even more complicated consensus seems to be that Hobbyking is overselling on the C rate. I've seen comments here that suggest anything from real C rate to be half, and all the way down to 1/10th of claimed C rate.
If it is hard to compare cell by cell, lets use a pack of 20s10p of 18650 compared to 20s30Ah lipo.
Lipo has discharge rate given in C value. Most 18650 batteries in A. Ie LG HE 2 is 20 A continuous and 30 A peak according to some websites.
How do I compare the discharge between those? To make things even more complicated consensus seems to be that Hobbyking is overselling on the C rate. I've seen comments here that suggest anything from real C rate to be half, and all the way down to 1/10th of claimed C rate.
If it is hard to compare cell by cell, lets use a pack of 20s10p of 18650 compared to 20s30Ah lipo.
Hillhater
100 TW
C rating is simply a ratio figure of the discharge current rating (Amps) , divided by the cell capacity (Ahr).
So, for your Lg HE example (a 3Ahr cell rated at 20 Amps max ?). It's C max rating would be 6.6. approx.
You might also want to consider voltage sag/ effective voltage, at those discharge levels.
So, for your Lg HE example (a 3Ahr cell rated at 20 Amps max ?). It's C max rating would be 6.6. approx.
You might also want to consider voltage sag/ effective voltage, at those discharge levels.
Allex
100 MW
Lipo - for those who still stuck in the early 2010s, who loves a rats nest, who loves to dedicate free time for balancing, who loves heavy, bulky and swallowing things
The only thing they are good for is R/C toys OR a special dragrace machine where you need extreme C rates in a small package.
The only thing they are good for is R/C toys OR a special dragrace machine where you need extreme C rates in a small package.
Ykick
1 GW
Allex said:Lipo - for those who still stuck in the early 2010s, who loves a rats nest, who loves to dedicate free time for balancing, who loves heavy, bulky and swallowing things
The only thing they are good for is R/C toys OR a special dragrace machine where you need extreme C rates in a small package.
Yeah, we're just dregs of society...
Allex said:Lipo - for those who still stuck in the early 2010s, who loves a rats nest, who loves to dedicate free time for balancing, who loves heavy, bulky and swallowing things
The only thing they are good for is R/C toys OR a special dragrace machine where you need extreme C rates in a small package.
Whats "in" for 2016 then for those that have no spot welders for 18650 cells?
whats good for me is lipo is modular. 10 miles ride slap on the 44v 10ah. 70 mile ride take 44v 40ah. Speed demon mood 56v 20ah.
ElectricGod
10 MW
Ykick said:Allex said:Lipo - for those who still stuck in the early 2010s, who loves a rats nest, who loves to dedicate free time for balancing, who loves heavy, bulky and swallowing things
The only thing they are good for is R/C toys OR a special dragrace machine where you need extreme C rates in a small package.
Yeah, we're just dregs of society...
OOH! Can I be a societal dregg too?! HAHAHA.
So...since LIPO's are so awful, I guess you are saying that 18650's are better? I guess I'm just stuck in the dark ages. ;P
Ohbse
10 kW
ElectricGod said:
That is the implication, yes
For anybody late to this party, you seriously should go 18650's for almost all requirements if you're building anything other than a toy. I don't mean that in a derogatory way, just that the time expense, complexity and risk that comes with Lipo packs are not something I would recommend on an EV that you rely on or use on a daily basis. I've built packs from lipo, used them on a daily basis for >1 year and literally worn out the connectors from reconfiguring the pack to charge, balance etc. There is thankfully now a better option
Spot welding is a problem largely solved with the advent of battery powered switched mosfet welders - I built my one before the JP welder was available for <$100 and have done many thousands of welds. The latest generation of high power cells are exceptionally energy dense while delivering a serious punch. Lifetime cost is lower than all lipo except possibly for the cheap hardcases on special, however you're going to invest substantially more time maintaining a sizable pack assembled from those.
All that being said, I'm looking to pull the pin on buying some Turnigy Nano-tech A-spec G2's to parallel up with a bunch of Samsung 30q's haha
Despite ElectricGod's highly aspirational username, he's not the highest authority on batteries
Ykick
1 GW
Ohbse - you may not mean what you’re saying in a derogatory way but that’s exactly how it comes across, IMO.
ElectricGod
10 MW
Ohbse said:ElectricGod said:
That is the implication, yes
For anybody late to this party, you seriously should go 18650's for almost all requirements if you're building anything other than a toy. I don't mean that in a derogatory way, just that the time expense, complexity and risk that comes with Lipo packs are not something I would recommend on an EV that you rely on or use on a daily basis. I've built packs from lipo, used them on a daily basis for >1 year and literally worn out the connectors from reconfiguring the pack to charge, balance etc. There is thankfully now a better option
Spot welding is a problem largely solved with the advent of battery powered switched mosfet welders - I built my one before theJP w elder was available for <$100 and have done many thousands of welds. The latest generation of high power cells are exceptionally energy dense while delivering a serious punch. Lifetime cost is lower than all lipo except possibly for the cheap hardcases on special, however you're going to invest substantially more time maintaining a sizable pack assembled from those.
All that being said, I'm looking to pull the pin on buying some Turnigy Nano-tech A-spec G2's to parallel up with a bunch of Samsung 30q's haha
Despite ElectricGod's highly aspirational username, he's not the highest authority on batteries
Glad I never said I was an expert on anything! I'm willing to try anything...at least once. What 18650's do you recommend and where did you buy them? One of the things I like about lipos is they are nice flat rectangular shapes so they pack together quite nicely with no dead space between them. Also, lipos are easy to work with since they solder together so nicely.
What about going with something like chevy volt battereis?
