Archived: the OG noob question thread! 😀

You could do it but you could drive without a fuel gauge or speedometer too but wouldn’t recommend it :slight_smile:

There is a serious danger of fire when over charging or over discharging cells why risk such an expensive component to save a few bucks?

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hmmmmm I know what you mean and are saying, but very few race vehicles have speedos or fuel gauges, not for the inexperienced user, but definitely do able.

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Thats why i buy only new same lipo pack and balance them on every charge, the discharge is always the same for all the cells (if packs have the same charge/discharge cycle) and never be an issue, if someone have an advice for the lipo pack to choose, i take any comment

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That is only because the driver has a team that has all those numbers figured out for him :slight_smile:

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Ok the search continues then thanks guys last thing I want is to skimp on the brain lol

That quote on the good quality cells is same thing I was told, glad to hear others think the same way. I’m still gonna pass on that BMS though thanks for the reply

Pass. Look at how the vast majority of battery builders including Damon build packs, and you’ll see that using a properly-rated balancing BMS is the current best practice for a reason.

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Like I said, you can always offer him to supply the bms. This way you know itll do what you need it to do. I supplied my builder with a smart bms for the added paranoia safety called “bluetooth” :rofl:

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Would you want your pack built by someone that would suggest this in the first place?

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Very true. I’d want to see his work. His opinion on bms or not bms wouldnt interfere with him doing good working packs. But it is a flag in itself

How does blutooth help with saefty is there a remote that u can use blutooth with?

@onebluesummer this is what I do with the bluetooth part.

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Yeah that is possible when you go 1s40p :stuck_out_tongue:

Or maybe it is all wireless…

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Now that is cool what BMS do you recommend?

I recommend the bms that fits your needs :kissing_heart:

The one I use is the ltt smart bms with bypassed discharge

https://www.lithiumbatterypcb.com/product/13s-48v-li-ion-battery-pcb-board-54-6v-lithium-bms-with-60a-discharge-current-for-electric-motorcycle-and-e-scooter-protection-2-2-3-2-2-2-2-2/

Note: if you want the extremely advanced features you need to buy the pc module (pictured in the first one⬇️)

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I don’t know of a good one, but I know JB Weld 8265-S is a terrible one. I tried it once and discovered it has actual steel in it, it’s not just a name :stuck_out_tongue_winking_eye:

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I would not trust that builder.

Furthermore, esk8 is the most demanding environment for a battery, most batteries are not built to withstand heavy vibration, especially high-discharge ones. Unless they know this will be in an esk8, and they have experience building esk8 batteries that don’t burn down, I would not go that route :wink:

This is like asking a commercial valve supplier for a gas valve, but declining to tell them you’ll be using on a lunar rover in heavy abrasive grit and temperatures from 260°F (127°C) to -280°F (-173°C) when only the best of the best valves last any reasonable amount of time.

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I’m an unaware of a BMS that doesn’t require a balance circuit for each P group. If there is such a thing I’d like to see it.

You can run a li-ion pack sans BMS, some people do as a space saving measure. I, in fact, have a 10s3p pack with no BMS for that reason. The truck is to charge to 95% and to not discharge past 30%. This obviously limits range. Also, I wouldn’t recommend in anything over 3p, it makes the self balance take a lot longer.

I manually balance my 10s3p on average every 3 discharge cycles. For over 2 years there’s been less than . 05v difference in the P groups.

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I see this term thrown around, but I don’t think it’s a real thing. In fact, it should be the opposite.

With no balancing, as a P-pack degrades, it causes it to charge faster than a healthy P-pack due to less capacity which tends to slightly overcharge it (eg: 4.3V versus 4.1V) and possibly overdischarge it. This would have the effect of exacerbating the situation as overcharging and/or overdischarging started slightly damaging the least healthy P-groups, only making the gap bigger, not smaller.

If you don’t have space for a BMS, there are “balancing boards” you can buy which are really tiny, and you don’t need much, even 5-10mA is a thousand times better than none. Or occasional external balancing.

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Oh boy, I’ve opened a can of worms now

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