Depends on the current draw of the ESC to the motor. If you’re going up hills, your ESC is going to be drawing a lot of current. I think 60A is the default Max current from the VESC. The ‘C’ rate is the battery’s discharge potential, where 1C = complete discharge of the battery in 1 hour (2C would be complete discharge in .5 hours). To calculate the discharge rate in amp hours, multiply the C rate by the capacity of the battery (eg. 20C battery 2 5000mah = 100A discharge rate).
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@Jinra and @lox897 Thanks for the help
Is there an easy way to charge all lipo’s at once by plugging in 1 cable into a charger? Much like a consumer grade board.
And voltage meters can be used to find out battery capacity remaining?
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be cautious about “20c” is key statements - it’s really C * Capacity of batteries - i would shoot for 100A discharge (normal not peak) to ensure you have overhead and don’t damage your batteries.
While lipos aren’t super expensive they aren’t cheap either. You shorten the life of the battery with heavy draw/demand. So utilizing less of the discharge capability will give you longer battery life. That’s why i shoot for a minimum of 100A continuous (not peak) discharge batteries (5000mAh * 20C = 100A). More is better but spending on 65C batteries is just throwing away money… IMO.
Similarly charging is a big part of pack life. Lower charging will get you more re-charge cycles (life), and not charging all the way to 4.2v will also help increase cycles/life. That said - i want maximum range, and usually still charge to 4.2, but do try to slow charge when i can afford the time.
Charging multiple’s @outsider - get a paraboard. There are cheap knockoffs, but the original paraboard is what you are looking for solution-wise. It allows you to connect 4-6 batteries (depending on which board and total amps combined charging) at the same time and balance charging them.
http://www.buddyrc.com/power-system/paraboard-parallel-charge-board/paraboard-v3.html
Just pick the connectors you need, or bare wire to solder your own (wish they would get xt90’s!). It’s also helpful to get some balance lead extensions to make it easier to plug in 4 batteries at once.
If you get a decent charger (i like iCharger but $$ - iMax B6AC v2 is my budget recommended), it can show you mAh charged and some other battery testing (like Internal Resistance - great info to see if pack is spent/shot/deadjim).
HTH - GL!
“consumer grade board” - you are asking about BMS. A single barrel plug and done like on your laptop.
A Battery Management System allows you to charge and discharge all the batteries to max and min safely. It likely (verify depending which you get) has a low voltage cuttoff, and will definitely have a balance/charge limit as well. Complexity wise i’ve avoided, but do like the idea for simplicity.
There are a TON of them out there and i don’t know enough to educate anyone, but hopefully someone will chime in or it can help you refine your search to good or suggested BMS’s.
GL!
hey sl33py, slightly off topic question. How come some lipos like this one have a 3s configuration but have 4 balance leads? When I was looking up some BMS’s they showed configurations for 1 lead per positive terminal in a series (example)
every battery will have one more wire than number of cells on the balance plug. 3s - 4 wires, 4s - 5 wires, etc.
(EDIT - it’s one power and the 3 grounds on a 3s)… let me go double check. I know they are in series, so you will see 4.2, 8.4, 12.6, etc.
uno momento
I had it backwards - one power wire, plus one ground x each cell.
here’s a good overview:
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So if I were to make my own battery like the example pic shown, I wouldn’t solder on that extra lead?
Buy 3 4S zippy 5000mah lipos. $30 each.
Bulk charging with power supply. Meanwell or other brands. Doesn’t monitor each cell and u have to do that on the side. I like this method way more than typical chargers
Can some one confirm the following:
You can combine any # of LiPo packs with different cell counts as long as the mAh and “C” rating is the same
ex-2s 5000mAh 20C in series with 3s 5000mAh 20C = 5s 5000mAh 20C
You can combine any # of LiPo packs with different capacity as long as cell count and “C” rating is the same
ex- 2s 4000mAh 20C in parallel with 2s 5000mAh 20C = 2s 9000mAh 20C
@LucidLunacy - correct. In Series, you are simply increasing voltage (2s - 7.4-8.4v (nominal to fully charged) + 3s - 11.1- 12.6v) so you will have 5s (19-21v).
Pairing brands might be wise and a battery monitor on each would be good to watch for the first cell reaching your cutoff/low-voltage. So you don’t overdraw and damage.
GL!
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Right on man, Thanks for confirming!
I’m using (9) 90c cells in series with (3) 35c. I’m watching the voltages and they stay balanced enough to keep everything within 4.2 and 3.6 and no not get warm or puffy. Why don’t I want to do this?
Long question. I am having a full blown BRAIN FART deciding what battery configuration to order for this… www.trampaboards.com/emtb-holypro-deck-with-vertigo-trucks-8-inch-superstar-wheels-ratchet-bindings-twin-motor-mount--motor--529e-p-12669.html I want a 12S 10A configuration on dual ollin boards. So is it better to run (2) 6s1p like these www.hobbyking.com/hobbyking/store/__8590__ZIPPY_Flightmax_5000mAh_6S1P_30C.html then put them in series with this series connector www.hobbyking.com/hobbyking/store/_10264__XT60_Harness_for_2_Packs_in_Series_1pc.html?strSearch=xt60 series then to ONE vesc and repeat for the other side? That would give me 12S2p 10A or …(4) 3S like these http://www.hobbyking.com/hobbyking/store/__14057__ZIPPY_Flightmax_2800mAh_3S1P_30C.html using the the xt60 harness x2 then a parallel connector like this one http://www.hobbyking.com/hobbyking/store/_64402__XT60_Harness_for_2_Packs_in_Parallel_1pc_AR_Warehouse.html?strSearch=parallel to get 12S 10.A plus?
Don’t understand u with he 10a
.im not sure I understand al, ur asking but I like the serial connection method give the host two options.
U can put ur batteries in series or parallel either way no problem ans determines the voltage. Everyone puts their escs in parallel and I think it’s the only way. Seperate batteries for each esc is doable
Esc is series?
I MEANT 10,000 mAh for distance… sorry…
I’m not sure what ur asking but if the motors are on either side there will either be long battery or motor wires. The esc will be better with the long motor wires. I’d do a series connection for the batteries to the two paralleled escs and one with reall long wires.
so let me see if this is clearer…battery pack 1 6S1P +SERIES CONNECTOR EQUALS 12S1P THEN A PARALLEL CONNECTOR EQUALS 12S2P TO VESC #1 6S1P
battery pack 2
6S1P +SERIES CONNECTOR EQUALS 12S1P THEN A PARALLEL CONNECTOR EQUALS 12S2P TO VESC #2 6S1P
A picture would do it all. Easiest is just make ur 12s battery, all in series, and have ur two escs coming off in a parallel circuit. And I have an xt90s plug at the beginning of the escs.
Words are confusing.
This is charging but then I plug it into the plug coming out of the two paralleled escs to go