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A123 Build with PCB mock up -Help me see problems

So I know they are heavier and not as NRG dense but really like the durability of the cell chemistry and the predicted life cycle.

I was thinking for a simple commuter on the flat river walk next to my apartment, a 12s3p of a123 26650 cells could be great.

I have some printed cells I used to mock up an build that never happened 26700 cells (why it sticks out the back)


Anyone see any problems with this? Just a slightly taller enclosure right?

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That is the planned current draw? Discharge bypassed?

That’s a lot of power and not a lot of weight.

I really like the LiFePO4 chemistry in a commuter board at 12S if extreme range isn’t your need. (Just long range but not extreme range :rofl:)

They feel hardly any sag at all, they have a super long lifetime, they are very good in very cold weather, and generally more robust than lithium-ion. Just less energy-dense.

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Your blue beast is partly to blame for this new infatuation.

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12s3p 26650 is a lot. Very bulky. 12s gives roughly 10s equivalent voltage. 14s is worth considering.

I’m running 3 boards with A123. 12s1p china hubs, 12s2p 2x6355, 15s2p hummie hubs. I do get some sag, and wish I did 14s2p on the 6355 build. But it’s okay with 12s.

And +1 to everything b264 said. But I’ll make a distinction between generic lifepo4 and A123.

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The cells are down to like 4.50 a piece now here in EU and I have no problem with a bit more volume. Yeah considered 14s as well need to find a BMS.

Your build is an excellent example of where the cell excels. Super high power density, lower energy density so ideal for short commutes.

More benefits:
You’re able to run low capacity with high discharge for airline travel
Higher voltage, lower capacity = faster “km per minute” charging
Super simple battery, no need for 50 cells to make a powerful pack

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Can I ask where you sources your BMS for the 15s pack …if you are running with BMS?

I’m using the smart bms with bluetooth in that build.

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/

Choose 15s lithium ion and leave a note that you want lifepo4. I use it for charge only, so 20a would be fine, but I think 20a and 30a have just fishpaper on the bottom, while higher amp ones have fets on the bottom, so get a metal plate with standoffs.

I’ll get you more info if you’re thinking of going this way.

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