Best battery cells for DIY projects

Prismatic LFP battery cells

If you want to build your own battery pack to use in an electric vehicle, renewable energy storage system or to replace the much heavier 12 volt lead–acid battery in your car this article might help you choose the right battery cells.

The recommended battery cells depend on the application. If you want a battery to power an electric vehicle, the battery should be compact and light. On the other hand, if you want a battery for an ESS (Energy Storage System) or to replace the 12 volt lead–acid battery in your car, it’s important that the battery has other characteristics.

I’ll divide the recommendations in two types of projects.

Project A

Main applications:

  • ESS (Energy Storage System)
  • 12 V battery

In this project battery cells should be easy to install and replace. The battery also needs to be safe, reliable, durable and with decent power energy. Volume and weight is not very important.


Battery cell format

Prismatic cells with screw terminals are perfect for the job. They are like LEGO, super easy to assemble together and also very easy to replace in future upgrades. No soldering required.


Battery cell chemistry

As for the best battery chemistry, LFP (LiFePO4) is my choice. It’s reliable, durable, safe and don’t cost a fortune (no cobalt used).

The only downside of LFP battery cells is their low energy density, but even that is being improved.


Let’s see the developments made by the Chinese battery cell maker ETC.

ETC battery energy density evolution


LFP (LiFePO4) cells have been improved regarding their energy density, while remaining reliable, durable, safe and affordable. Not requiring cobalt is a major quality of this battery chemistry. These sturdy cells are popular for ESS (Energy Storage Systems) and electric buses.


The second-generation LFP 206 Ah cells are already available to private buyers. Let’s see the specs of these cells in more detail.

LFP206S battery cell specs


With the energy density increase, this second-generation LFP battery cell isn’t much different to the exceptional Samsung SDI 94 Ah battery cell, with the extra benefit of using no cobalt.


For DIY projects I wouldn’t recommend battery cells with great specs if they aren’t easy to buy nor affordable. The second-generation 206 Ah LFP battery cells from ETC can be bought for around 190 euros per kWh in here. Moreover, in most countries you’ll avoid import duties and taxes.


Summing up, I recommend these battery cells because:

  1. Prismatic with screw terminals (very easy to assemble or replace)
  2. Safe (won’t catch fire even if punctured)
  3. Reliable (work great in most temperatures)
  4. Durable (extremely high cycle life)
  5. Environmentally friendly (no cobalt)
  6. Affordable (around 190 euros per kWh)
  7. Easy to get (Chinese sellers will actually sell and send them to you)



Project B

Main applications:

  • Electric vehicles
  • Portable power banks

In this project battery cells should be as light and compact as possible. Volume and weight is very important.


Battery cell format

Cylindrical cells are small enough that allow to build battery packs in every shape possible. Years ago the 18650 format was dominant and alternatives were almost nonexistent, but now the 26650 format is gaining popularity, especially for electric bicycles.


Battery cell chemistry

NCM and NCA are the most energy dense chemistries, therefore are the recommended for this project. These chemistries are very popular in cylindrical cells.


In my opinion LiitoKala has the best battery cells for this project. The LiitoKala Lii-50A in the 26650 format is my recommendation. The downside is that you have to solder these cells to assemble the battery pack, unless you buy one already made and ready to use.

LiitoKala Lii-50A


For DIY projects I wouldn’t recommend battery cells with great specs if they aren’t easy to buy nor affordable. These battery cells can be bought for around 192 euros per kWh in here.


Summing up, I recommend these battery cells because:

  1. Size (small cells give you flexibility to build battery packs in many different shapes)
  2. High energy density (essential for small and light battery packs)
  3. Affordable (around 192 euros per kWh)
  4. Easy to get (Chinese sellers will actually sell and send them to you)


Have you ever completed a DIY project involving batteries? Ever thought of building your own customized version of a Tesla Powerwall?

Pedro Lima

My interest in electric transportation is mostly political. I’m tired of coups and wars for oil. My expectation is that the adoption of electric transportation will be a factor for peace and democracy all over the world.

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2 years ago

Nice to read you, as usual.
This makes me think about electric scooters and mopeds, the affordable ones – Askoll, Vmoto… Most of their batteries suffer from premature degradation that makes them almost unusable after 10k-20k kms. Could these prismatic batteries improve the original packs? Is it easy to make larger packs? Or perhaps it is tricky due to the electronics. I do not have much knowledge on this.

2 years ago
Reply to  Pedro Lima

I have just moved to Indonesia. There are millions of 2-stroke scooters here, and the air pollution is terrible. I would love to see electric scooter manufacturers move into markets like Indonesia and India, etc.

Would the LFP cells work in an e-scooter? Or are they too big or heavy? 10 cells would be ~42kg, which is heavy, but I think it might work in a scooter. And 10 cells would mean ~6-7 kwh.

Would it be better to use the cylindrical cells, or would they degrade too fast in the heat?

2 years ago

The title is a bit misleading…
A lot – if not most ! – of DIY project is about micro-mobility, not Tesla Power-wall.

Like converting to ebike existing bicycle, or to maintain on the road VAE, electric scooter, gyro-wheel, light motorcycle, Hoverboard, etc.. which all require the making of a battery.

The cell presented here is not then the “Best battery cells for DIY projects”
What would it be for the micro-mobility application ?

2 years ago
Reply to  Pedro Lima

Interesting, I always tough LiitoKala is poor quality Samsung copycat. is usually the way to go to avoid such…

So LiitoKala is good stuff ?

2 years ago

Oh way too cool! The price seems cool too, I’d love to build my own “Powerwall” and for 2000€ for the batteries it might even be affordable, just a shame I’m no electrician and have no knowledge… darn.. but to be spending 10’000€ on a ready to use Powerwall, just to have a battery, does not justify the expenses, it will never “pay off”..

2 years ago

I guess you can’t use the LFP cells for an off grid ESS in Canada, as the cells might get wrecked if the temperature goes below -20C. Many people in Canada have cottages that are off grid, so there’s a market there for storage systems + solar panels. They all use Lead Acid right now.

2 years ago

Thanks for this article.
Why do we have year 2018 quarter 1 (18Q1) in the graph but the batteries are only now being released? Was a Too optimistic timeline plan as Tesla? 🙂
Also a note that 190€/kWh doesn’t seem cheap as we have already Tesla doing 100$/kWh …

2 years ago

This is fascinating. So I can get about 10kwh of decent batteries for about £2k?

Realistically how hard would it be to turn these into a powerwall? Are there any significant downsides? Why aren’t we seeing lots of cheap competitors to Tesla? I hear they’re charging about £7k?

2 years ago
Reply to  Pedro Lima

Thanks Pedro,

What do you recommend for the part of deciding+allowing the system to charge or discharge the battery?
(I Imagine the basic option is to charge the difference “producing – consuming” (when house is producing more than consumes) and discharge the amount “consuming – producing” (when consumption>production);
(We also can go further and make smart algorithms to only discharge if we are in a expensive hour to buy electricity… and even charge during the night for cheaper electricity : this would allow a lower kWh battery solution for the house)

2 years ago

hello pedro, next month I install 19.8 kW photovoltaic system on my flat roof, on my order is written ‘inverter fronius from September ready to install solarwatt or byd storage battery’, I know that byd batteries are lifepo4, do you think that i can buy these LFP206S cells with an appropriate bms (I hope the inverter fronius handles the charge/discharge properly) ? can you recommend a bms suitable for about 40 kWh of these cells ? i think the current fronius symo hybrid three-phase inverter use fronius battery modules with nominal voltage 51.2 volts, my inverter is 20 kW

2 years ago

Hello Pedro. Another great article has always.You recommend this store based on your personal experience or based on your research?

2 years ago

Agree. Good for energy storage and larger vehicles. One drawback is energy density though. 18650 has about 270 wh/kg while these have 160 wh/kg. So for everything on two wheels I’d say 18650 or the 28650 are still the best.

2 years ago

Service life only 5 years?!

2 years ago
Reply to  Ari

Yes, I also have this question: Regarding the 206 Ah LFP case we see a 3000 cycles lifespan (the LiitoKala is even worse: 500). If we consider a cycle per day we get 8,22 years (3000/365). Doesn’t seem much if we compare e.g. with this 10000 cycles’ LG Lithium technology: (although 4X more expensive we don’t need to redo installation work as often and is more eco-friendly, reducing disposables) By the other hand, Tesla powerwall just give us 10 years warranty (

2 years ago

Very interested!