Help: Turnigy vs Multistar?

[Raichuboy18]

I plan on building my first RC LiPO battery pack this year for my ebike and was planning on getting this Turnigy battery pack (http://www.hobbyking.com/hobbyking/store/__18631__Turnigy_5000mAh_4S1P_14_8v_20C_Hardcase_Pack_US_Warehouse_.html). I saw this Multistar pack on sale though (http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=66486) and wasn't sure if I should abandon the other pack for this one.
Here is my plan: ebay 48v kit, 48v 12s battery, 26" wheel, 25A BMS (because I am paranoid and want to deal with less stuff when charging), and my weight is 170. I am hoping to do 30 mph pretty reliably. Does the Multistar seem like a good fit? I plan on upgrading my motor later, to the leaf motor 1500w.

 

[brumbrum]

According to test data of the 16ah multistar as seen on this forum you will be able to draw a constant 4C discharge from this particular brick which equates to 64amp constant draw so you would be able to get approx 2800w of constant power with your 12s setup if you wanted to. Plus the 3 bricks should be a lot easier to build with too.

Edited due to getting my math completely wrong!

 

[Raichuboy18]

According to test data of the 16ah multistar as seen on this forum you will be able to draw a constant 4C discharge from this particular brick which equates to 64amp constant draw so you would be able to get approx 2800w of constant power with your 12s setup if you wanted to. Plus the 3 bricks should be a lot easier to build with too.

Edited due to getting my math completely wrong!

How does it compare to the Turnigy one though? Are they equally stable/long lasting?

 

[brumbrum]

In a non scientific way, the amount of money you will save with the multistars (if building same size pack with either cells) will surely outweigh any benefit of the hardpack cell cycle life being any better than the multistars. I imagine they will have similar cycle life anyway, but that is purely a guess. And btw they are both made by Turnigy but i guess the hardcase cells just have lower internal resistance so they can have a higher discharge rate which you would not need for your application.

 

[motomech]

I plan on building my first RC LiPO battery pack this year for my ebike and was planning on getting this Turnigy battery pack (http://www.hobbyking.com/hobbyking/store/__18631__Turnigy_5000mAh_4S1P_14_8v_20C_Hardcase_Pack_US_Warehouse_.html). I saw this Multistar pack on sale though (http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=66486) and wasn't sure if I should abandon the other pack for this one.
Here is my plan: ebay 48v kit, 48v 12s battery, 26" wheel, 25A BMS (because I am paranoid and want to deal with less stuff when charging), and my weight is 170. I am hoping to do 30 mph pretty reliably. Does the Multistar seem like a good fit? I plan on upgrading my motor later, to the leaf motor 1500w.

Turnigy 20C has been my default Lipo for several years, but have recently switched over to Multistar.
I have had no problems w/ bad cells w/ the Turnigy, but I haven't been impressed w/ it's service life. After a year or so, it just doesn't have "oopmh" it had when new.
So far, my Multistars have been great, the cells stay in perfect balance if I stay within the 80% Depth of Dis-charge rule. Time will tell how long they last.
As for the "hardcases", they are good for installations where the bricks are vulnerable to impacts, but their plastic shells take up space. Besides, to get 15 Ah capacity, you would need 9 configured 3S/3P, way too complicated!
If you have space to fit them (they are large), 3 of the Multistars configured 3S/1P would make a decent and simple 12S pack of 16 Ah. I would replace the XT60 connectors w/ 4 mm bullets for easy serial connection and you will have to build new balance leads to end up w/ 2) 6S taps.
Forget the BMS, it's not needed and is just another thing to go bad. Your controller should have a LVC @ 41 Volts, perfect for 12S and that, plus a Voltmeter, is all you need for the dis-charging cycle.
To charge, you should use a bulk charger and two Battery Medics for ck'ing and balancing the cells. There are Mean Wells that fit any budget, but I use the fantastic HLG series;

 

[Raichuboy18]

Forget the BMS, it's not needed and is just another thing to go bad. Your controller should have a LVC @ 41 Volts, perfect for 12S and that, plus a Voltmeter, is all you need for the dis-charging cycle.
To charge, you should use a bulk charger and two Battery Medics for ck'ing and balancing the cells. There are Mean Wells that fit any budget, but I use the fantastic HLG series;

Thanks for the info! Would adding a BMS increase or decrease the complexity of charging? That is the main reason why I want it. It seems like I will have to deal with less wiring when charging if I have one. I will forget about it for now because if I don't have to spend the money, I won't, but I would like to make things simpler for myself later on.

 

[motomech]

You keep things simple by keeping the pack simple.
1P, or 2P @ the most. That way you can bulk charge w/ a Mean Well and ck and balance the cells w/ 2) Battery Medics, or 4) @ the most.
With today's large capacity bricks, there is no need to configure packs 3P or more to get the system capacity you want.

 

[Raichuboy18]

You keep things simple by keeping the pack simple.
1P, or 2P @ the most. That way you can bulk charge w/ a Mean Well and ck and balance the cells w/ 2) Battery Medics, or 4) @ the most.
With today's large capacity bricks, there is no need to configure packs 3P or more to get the system capacity you want.

Could you link me where to get the meanwell and bulk charger? I'm hoping to spend around 120$ on the charging system. Is that reasonable?

 

[motomech]

Where are you at???
You need to fill out your profile.

 

[Raichuboy18]

Where are you at???
You need to fill out your profile.

Fixed?

 

[motomech]

There are any number of suppliers for Mean Wells, just Google Mean Well power supply.
More important is which HLG to get.
The 320H I have is the most powerful and will charge my 20Ah pack in a little over an hour
Even Multistar w/ it's low C rate will accept that fast charge, so there is no reason mot to get the 320H except price.
Make sure you order the one with the suffix A!

Battery Medics;
The blue ones in my pic are the best, but no longer avail.
The black ones are avail. @ HK (West warehouse);
http://www.hobbyking.com/hobbyking/store/__41170__HobbyKing_8482_Battery_Medic_System_2S_6S_US_Warehouse_.html
They can be prone to over-heating and I add a 12V mini-fan (Ebay) and this one has a switch as well;


*(As w/ all HK products, wait a couple of minutes for a discount pop-up)

If you use 3) 4S bricks to make 12S, you will have 3) 4S taps.
The easiest solution is to use 3) Battery Medics.
Splice the fan leads across the JST 4S extensions for full 4S Voltage.
http://www.ebay.com/itm/3Pcs-Silicone-Wire-2S-3S-4S-JST-XH-Balance-Extension-20CM-Adapter-Cable-RC-Lipo-/391534906545?hash=item5b294c8cb1:g:6xAAAOSwU-pXs5qk
Lastly, 4 mm bullet connectors can be had on Ebay;
http://www.ebay.com/itm/5-Pack-5-Turnigy-HXT-4MM-Bullet-Connector-Plug-Housing-Sets-for-Lipo-ESC-/391377935648?hash=item5b1ff15d20:gIQAAOSwbqpTr3~x

 

[motomech]

And Luna Cycles has a nice low-cost Voltmeter to monitor your pack while riding.
http://lunacycle.com/batteries/gauge/luna-voltage-meter/
Their head lights are great too!

 

[Ianhill]

I use the exact setup u mention , 12s 16ah multistars, I got 3 4s2p bricks as they are cheaper than the 6s2p, I discharge them at 60amp and get a small voltage drop on full load so they perform very well for the price and around 50 cycles in I have no noticble capacity loss yet but I look after them make sure never to discharge below 3.70v per cell around 14.8ah discharge and they will look after you then.
I get around 15 miles of 3kw at full charge dropping to 2.6kw nearing empty going up steep hills mudpaths wheelspinning about and it barely warms the pack up for the price there is no better low discharge pack I believe that why im going to use 16s20ah multistars on my next project as they work well at low discharge, very compact and cheap as chips.

 

[Raichuboy18]

There are any number of suppliers for Mean Wells, just Google Mean Well power supply.
More important is which HLG to get.
The 320H I have is the most powerful and will charge my 20Ah pack in a little over an hour
Even Multistar w/ it's low C rate will accept that fast charge, so there is no reason mot to get the 320H except price.
Make sure you order the one with the suffix A!

How do you wire the HLG to charge? I don't know anything about them since I wasn't intending to build my own charger, but now that you said it charges your 20Ah packs in around an hour I am super interested! I was looking at this: https://endless-sphere.com/forums/viewtopic.php?f=3&t=62174 but I want to get a second opinion. Also, would a simple XT90 to Bullet connector work, or would it be best to replace the XT90 entirely?

 

[Raichuboy18]

I use the exact setup u mention , 12s 16ah multistars, I got 3 4s2p bricks as they are cheaper than the 6s2p, I discharge them at 60amp and get a small voltage drop on full load so they perform very well for the price and around 50 cycles in I have no noticble capacity loss yet but I look after them make sure never to discharge below 3.70v per cell around 14.8ah discharge and they will look after you then.
I get around 15 miles of 3kw at full charge dropping to 2.6kw nearing empty going up steep hills mudpaths wheelspinning about and it barely warms the pack up for the price there is no better low discharge pack I believe that why im going to use 16s20ah multistars on my next project as they work well at low discharge, very compact and cheap as chips.

Awesome! I plan on using this bike quite a bit to get to and from campus so I will be collecting a ton of data on it's voltage and capacity over time. Hoping they will last me at least a year!

 

[Ianhill]

Those meanwells are designed to drive LEDs so typically they only output around 10amps max the best PSU for bulk charging and still good value has to be this hp 48v 2000w PSU $30 and can push out 40amps and can be used in series
http://m.ebay.com/itm/381754117189

 

[Raichuboy18]

Those meanwells are designed to drive LEDs so typically they only output around 10amps max the best PSU for bulk charging and still good value has to be this hp 48v 2000w PSU $30 and can push out 40amps and can be used in series
http://m.ebay.com/itm/381754117189

How would I set up these chargers? I don't know anything about it so I don't really know how to judge for myself. Please link me something that will teach me what I need to know. This does look pretty awesome though, especially for the price

 

[motomech]

No whining please.
Click on my name, go to my posts, search w/keywords "mean well HLG-320H-054A" and read.

 

[motomech]

The 320H I have is the most powerful and will charge my 20Ah pack in a little over an hour

Is it a 12V pack?

Ok, I'm busted
I never discharge the full pack, usually to 50 or 60% and that's what I had in mind. my bad.
But these power supplies are way faster than a balance charger of equal rating because they don't start and stop to read the cell values. Just 7 plus Amps from the moment it's plugged into the battery til the moment it's unplugged.

 

[Ianhill]

No u can't put a battery espicially lipo direct to the PSU supply its resistance is to small it will demand very high current, you still have to use a DC to DC CC.CV charging board to regulate what the battery's can take then a means of checking the voltage and current going in so a shunt gauge of some sort and a way of balancing the cells I use a 300w 10s rc charger myself but for a large pack 20s+ etc I can see the appeal of this method mentioned but I would only suggest it to those with sime electrical knowledge.

 

[Raichuboy18]

No u can't put a battery espicially lipo direct to the PSU supply its resistance is to small it will demand very high current, you still have to use a DC to DC CC.CV charging board to regulate what the battery's can take then a means of checking the voltage and current going in so a shunt gauge of some sort and a way of balancing the cells I use a 300w 10s rc charger myself but for a large pack 20s+ etc I can see the appeal of this method mentioned but I would only suggest it to those with sime electrical knowledge.

Ok, so what I am getting from this is don't build a charger yet. Go for something that is pre-made until I have done more research on building these things (Probably a good idea xD). Any pre-made RC chargers/dischargers that you would recommend? I was thinking of the SKYRC RS16 before this.

 

[Ianhill]

Never used one myself they look well made though, I can vouch for the icharger1010b+ its very capable upto 10s and 10amp per cell but it needs a seperate PSU to run it so I use HP server PSUs there's is lots of information on how to get them to turn on safely and they are robust very easy to find on eBay and cheap.

 

[Raichuboy18]

Never used one myself they look well made though, I can vouch for the icharger1010b+ its very capable upto 10s and 10amp per cell but it needs a seperate PSU to run it so I use HP server PSUs there's is lots of information on how to get them to turn on safely and they are robust very easy to find on eBay and cheap.

Alright, thanks so much! I will Just run with the SkyRC since it's plug & play, and allows me to have a read out on my computer.

 

[Ianhill]

The icharger has a USB and computer disc to setup discharge graphs etc but the sky rc looks just as good if not better for a 6s setup, I can't really recommend a charger as I had mine around 3 years and not checked the market to see what's available but I did like the icharger 4010duo but thats a 20s beast.

 

[motomech]

No u can't put a battery espicially lipo direct to the PSU supply its resistance is to small it will demand very high current, you still have to use a DC to DC CC.CV charging board to regulate what the battery's can take then a means of checking the voltage and current going in so a shunt gauge of some sort and a way of balancing the cells I use a 300w 10s rc charger myself but for a large pack 20s+ etc I can see the appeal of this method mentioned but I would only suggest it to those with sime electrical knowledge.

What a bunch of nonsense!
Breaking(disconnecting) a 12S pack every time to charge is the absolute worse thing to be doing. It not only makes it harder to keep the cells in balance, it opens up the door to accidents.
That's why so many of us have moved away from the unreliable Toy chargers and gone to bulk charging.