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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?


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.


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.


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.

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.