Two 10s2p with a switch for using independent, help

I have this double hub esk8 with a 10s2p battery. A couple days ago I broke my deck and since I have another 10s2p pack im looking for using both so I can get more range. The two packs arent the same so im too scared to use them on paralell. Thats why I want to conect one or two switches to charge to one or the other pack and to switch between the batteries output to the esc.

Thing is I’m not sure how to do it cause the first pack has the pair of cables from the charger plug to the bms and then another pair from the bms to a xt60 plug to the esc, meanwhile the other pack has only the xt60 plug I’ll upload some images

So my idea is using a switch from the charger plug to choose wich battery to charge and another switch to choose from wich battery power the esc, is my theory correct?

Also I asume I will need to sodder a couple cables from the pack that only has two cables to the switch I’m installing after the charging port, is that right? and if correct, where in the bms (in the picture) should i sodder the cables to the charging circuit?

this is the idea on drawing lol:

if my theory is correct, is this type of switch correct?: spdt-on-off-on jpg

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If you are using two different battery for a board, you should make sure they both can give out the same power the esc was programmed to consumed. If not, you’re gonna have a bad time.

My recommendation would be to not do it until you know what battery you have and it’s discharge rate.

Now if you did have the two and are afraid to go parallel, you can do a reserve connection, but that will require you to create another wire connector that connects that battery to the esc and with an antispark switch or a loop key. So basically, it’ll be two switches. The main and the reserve.

Don’t ever mix two different batteries.


i just edited the main post with picture and more info, could you check my theory please?:slight_smile: and yes i dont trust to going parallel, and at least i did proove each battery and both seem to work fine with the board

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Now about that switch, that switch must have the amp rating that can handle the amps it needs to go through. This is where I will lack the knowledge for since I usually make two switches (like the power on/off type) on my board for reserve power battery. The charging doesn’t matter if they’re both 10s2p since that will be dealt with via the bms. So you can charge both bms with one charger (unsure about this one. I heard you can charge both pack with one bms, which would likely work) . Or you could be like me and just buy two chargers and make two holes for the charging.


Someone else with more knowledge about it should help you with this.

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so for the switch from the packs to the esc i wanna be sure it supports at least the same amount of amps as the esc, am i right? english is not my native language.

and if so, how can i check how much amp does that switch need to handle? i asume is checking the serial of the esc or something but if i cant get that info from the printing how can i know? i have a multimeter lol…and if you have a picture or link for the one you mean, that ill be great

Think of it as not burning your switch. Normally, switches like those has something called amp rating and what they’re rated for. This is where you need to know what battery you’re using. But you can get a switch with a high amp rating. It saves a bit of trouble trying to figure things out.

It’s exactly the one you sent, but unfortunately, you need a switch that’s rated for continous amps. Most are rated for 12v max. Larger ones won’t fit your board. That’s why you don’t see many people using switches lately. Well, save for lights and stuff.

My suggestion would be to just do a loop key and charge the battery separately. But that’s me. You can try an antispark switch.

Like so:

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It’ll look like this.

The charging wires can also have something to change charging channels, but I don’t normally do this.

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thank you so much for the detailed info!!

long shot question (maybe): specs

thats all the info i have from my board, is there a way to estimate how many amps the switch should handle?

If you mean my antispark switch, it can handle it fine. If you meant your switch, it has to handle 36v, which is on the battery. Most switch are not rated for that sadly. If there is one, the switch will say in the store how many amps its rated for as shown here:

This is how you’ll know if it works. The example here is different. Note: make sure it’s a DC switch. It will say vdc.

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What I meant is that your switch can handle 100amps, how can I know how many amps I’ll be supplying so I can choose maybe a cheaper one or one I can find here in my city

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This is where you need the info of your battery. I won’t know at all. What you shared didn’t tell me the amp of the battery, which is current. This is where it usually gets complicated. I had a 10s2p that I still don’t know the amps to this day.

Just a small info: some boards have Chinese batteries. They are custom made and aren’t easy to find. You need to test discharge yourself by ripping off one from the pack.

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this one is 4.4 and the other one is either 4.4 or 1.8

so i need a swithc for both bateries for at least 8.8 a or one switch for each battery for at least 4.4 A?

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A few notes here: what is given is the capacity of the battery. This isn’t the discharge rate of the battery.

Discharge rate would be what I’m referring to, which unfortunately, Chinese batteries do not label on the pack.

So here’s a good example to clarify what I mean:

My battery pack is a 630 wh battery pack. The amp hour from my pack is 17.5ah.

But… my batteries are samsung 35E cells, which is rated for around 8amps of current.

So my pack is a 10s10p, so 80Amps of current is given out from my pack.

This is where the Chinese batteries do not label. The amps the battery produce or discharges. This is where you have to take one battery out and use a device to read its discharge.

To know what battery you have, you have to slightly open the battery pack up. I opened mine to fix my bms…

Like so:

See where it says INR18650 35E? Samsung? That’s the info needed to search up what battery is it.

You cannot use the AC current rating for a switch being used for DC current! The DC current rating is much lower since the voltage is always at the full value but AC voltage swings between high and low values and the switch often is not switching at a high current level.

Using an AC-rated switch with DC current will result in much shorter life unless you derate the switch.

The DC current and/or voltage ratings are typically 1/5th to 1/10th of the AC ratings but you will have to check the datasheet to be sure.


I tried finding one for DC but I guess I didn’t search for DC switches. This was my mistake. Thank you for this info.

Look up falconpev solid state switched relay for paralled batteries. The smaller compact version would work for easily switching between the packs. Might help what you are looking for.

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Thx for the info, I have bought a switch which for testing it works but I don’t know if it will withstand the current when riding.

So far so good about my proyect, I need to finish the enclosure and I’ll upload a post about my build

Thanks to everyone who helped me in different posts!!

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