Where This Guide Comes From

This article is built from one source video — Will Prowse's "Why are people NOT buying raw LiFePO4 cells?", watched more than 2.6 million times on the DIY Solar Power with Will Prowse channel. Will is one of the most trusted voices in DIY solar, and in this video he walks through the numbers that have changed how hobbyists buy battery cells: raw cell sales through his affiliate links have dropped to zero, while pre-assembled server rack batteries keep getting cheaper. Every figure and recommendation below is taken from that video.

DIY Solar Power with Will Prowse — "Why are people NOT buying raw LiFePO4 cells?"
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2.6M+ views. The price-per-watt-hour math that pushed DIY buyers from raw 280Ah cells to turnkey server rack batteries — and when building your own pack still makes sense.

If you are planning a home battery bank, an RV system or an off-grid setup, the single biggest decision you will make is not chemistry or capacity — it is whether to assemble cells yourself or buy a finished battery. Will's video shows that the old DIY math has quietly inverted: server rack batteries now cost nearly the same as the raw cells they contain, and they come with a warranty, a BMS and zero assembly risk. Below is the full breakdown, with every number taken from the video.

Why Buyers Stopped Choosing Raw Cells

The video opens with a striking admission: the number of people buying raw LiFePO4 cells through Will's affiliate links is now zero. One distributor he talks to reports that sales of spare cells have dropped drastically. That is not a quality problem — the cells themselves are excellent. It is a price problem. When four 280Ah Grade A cells cost nearly as much as a fully assembled server rack battery, the DIY route loses its main advantage: saving money.

The economics shown on camera are blunt. Four 280Ah cells give you roughly one kilowatt-hour of storage, and at the prices Will quotes that works out to about 24 cents per watt-hour. For a little more — about five dollars per watt-hour of finished product, by his estimate — you can buy a complete server rack battery: Grade A cells, a quality BMS, a warranty, and a metal case. Once the gap between loose cells and finished packs shrinks that far, most buyers stop doing the work themselves.

What a Server Rack Battery Gives You That Cells Don't

The appeal of a server rack battery is that everything hard about DIY is already done. Will lists what you actually get: Grade A cells guaranteed by the vendor, a warranty you can claim, a quality BMS with real current ratings, and no need to match cells. You do not have to worry about top-balancing, cell matching, torque settings, busbar sizing or compression — you buy it, put it in a box, wire it to your inverter, and that is it.

That last point matters more than most first-time builders realize. The most common DIY failures are not dramatic explosions — they are slow problems: a weak BMS that misses an overcharge, mismatched cells that drift apart, a loose busbar that heats up. Every one of those is designed out of a turnkey pack. For a homeowner who wants reliable backup power, that engineering margin is worth a lot.

The Real Price Comparison: Cells vs. Turnkey Packs

Will walks through the math twice in the video. First, the honest case for raw cells: if you can find good cells at a very low price — he quotes a deal at well under 20 cents per watt-hour — DIY still wins on cost. But he notes that the best prices historically came with long AliExpress shipping times and real uncertainty about what grade you would receive. Today, with server rack prices where they are, you can often get an assembled pack for close to the same per-watt-hour cost as loose cells, with none of the wait and none of the risk.

His conclusion is direct: it has become very hard to compete with the price of a server rack battery using loose cells — unless you catch a genuine deal from a trusted domestic distributor. That is why he now keeps American distributors with Grade A cells as his recommendation for buyers who still want to build their own packs.

When Building Your Own Pack Still Makes Sense

The video is not anti-DIY — far from it. Will makes clear that there are still excellent reasons to assemble cells yourself. If you need a specific voltage, capacity or form factor that no off-the-shelf pack offers, or if you genuinely enjoy the engineering, DIY gives you freedom no turnkey product can match. And for applications that need high discharge rates — EVs, inductive loads, or anything that regularly pulls 2C or more — raw cells designed for EV use are often the better choice, because server rack batteries are typically built for slower solar charge and discharge cycles.

The honest trade-off, as one commenter with hundreds of likes puts it, is that DIY is for people who want to understand and maintain their system. If a warranty and plug-and-play reliability matter more than the satisfaction of building, the server rack route is the rational choice. If you want maximum flexibility and are prepared to accept the responsibility, raw cells still have a place.

Choosing Grade A Cells: Why EVE Gets the Recommendation

For builders who do go the raw-cell route, Will is specific about which cells to buy: Grade A EVE 280Ah cells. In his experience — and, he says, in the experience of every distributor he has asked — EVE cells have fewer problems and better quality control than other brands he has tested, including cells he specifically warns about. He notes that EVE cells may cost a bit more than some competitors, but they have thicker walls, consistent capacity and a much lower rate of complaints. When a distributor tells him "no one has ever complained about EVE cells," that is the kind of track record he trusts.

His advice for first-time builders is to buy from a distributor that handles returns, rather than gambling on an AliExpress shipment that takes four to five months and leaves you with no practical recourse if the cells underperform. A domestic distributor with a return policy costs a little more and removes almost all the risk.

Charging and Storage Rules That Protect Your Pack

The video closes with charging guidance that every LiFePO4 owner should follow, and Will points to forum data and studies backing it up. Three rules stand out: charge LiFePO4 to 100% and discharge it to 0% at least once for proper balancing; keep idle packs at around 50% state of charge; and store them in a cool environment. He also warns against setting charge voltages so low that the BMS never triggers its balancing circuit — balancing needs headroom to do its job, and a battery that never balances will slowly drift out of performance.

A useful detail from the video: LiFePO4 cells used in solar applications are cycled at much gentler C-rates than EV cells, which is why the same cells that push a car can comfortably serve a home battery for 15 to 20 years if the voltage windows are set correctly. Following these rules is what makes a DIY pack last as long as a turnkey one.

Buying Channels: Domestic Distributors vs. Direct Import

Where you buy matters as much as what you buy. Will's point is simple: good cells are available from good distributors with good return policies, but the tempting low prices on marketplaces usually mean long waits and no recourse. He contrasts a four-to-five-month AliExpress order with a domestic distributor who can answer questions and honor returns. For most people, the domestic route is the right one — even if the per-watt-hour price is a little higher, the total cost of the DIY experiment is far lower when your cells actually arrive and perform as advertised.

Our Recommendation

If you are building a home backup system, an RV bank or an off-grid setup and your priority is reliable power with minimal fuss, the video's logic points clearly to a server rack battery with a warranty. If you need a custom voltage, capacity or discharge rate that turnkey packs cannot deliver — or you simply enjoy the build — then Grade A EVE cells from a domestic distributor are the right raw-cell choice, and the charging rules above will keep them healthy for well over a decade.

At Dajiu Energy we manufacture LiFePO4 batteries to order — drop-in replacement packs, wall-mounted home storage, portable power stations, commercial energy storage and more — so whether you are replacing lead-acid or engineering a custom bank, we can build the voltage and capacity you need without you assembling a single cell. Tell us your requirement and we'll engineer it. Our product range covers LiFePO4 drop-in replacement batteries, EV and golf cart batteries, wall-mounted home storage, portable power stations, commercial energy storage and battery swap cabinets — explore the full lineup in our product center, or browse more buying guides.

Reviewed by Dajiu Energy Engineering Team — a Chinese LiFePO4 battery manufacturer building LiFePO4 batteries for RVs, homes, golf carts and portable applications since 2017, serving OEM/ODM projects with CE, UN38.3, MSDS and ISO9001 certified builds.

What Viewers Are Asking (Top Comments on the Video)

These are the most useful of the video's top comments, with our practical answers. The original creator did not reply to these threads, so the answers below are ours — written the way we'd answer a customer on the shop floor. Thanks-only comments were left out on purpose; these are the ones with actual information in them.

@Rick Robinson · 798 likes
"I would love to see you look at how to do a whole house backup system using server rack batteries. Call it a Tesla Wall killer."
Our take: That is exactly where server rack batteries shine. A whole-home backup usually needs 10-20 kWh, and rack batteries stack modularly on a standard 19-inch rack: start with one 5kWh unit, add another when the budget allows, and each addition is plug-and-play. A rack battery plus a hybrid inverter gives you grid backup, solar charging and generator input in one cabinet — the same architecture as a name-brand home battery at a fraction of the cost per kWh.
@ellooku · 366 likes
"People are not buying it because it is unreasonably expensive."
Our take: That is the whole point of the video. At roughly 24 cents per watt-hour, loose cells used to undercut finished batteries by a wide margin. Now that turnkey packs have dropped to near the same price per watt-hour — while including a BMS, case and warranty — the cost argument for DIY has mostly disappeared. The exception is catching a genuine deal from a domestic distributor, which is exactly what Will recommends.
@Ps Rohrbaugh · 260 likes
"DIY lithium batteries have a HUGE stigma in the RV community. Every single person I have told about my DIY battery has responded negatively. But the flexibility of a custom pack is unbeatable."
Our take: The stigma is real, and it usually comes down to insurance and liability — an un-certified DIY pack makes some RV insurers nervous. But the flexibility point is fair: a custom 12V or 48V pack sized to your exact bay dimensions and amp draw is something no off-the-shelf unit matches. The practical middle ground is buying a certified turnkey battery for insurance peace of mind, or keeping a detailed build log and photos if you DIY so you can document the quality of the assembly.
@Oktokolo · 151 likes
"TLDW: No one buys them, because they are overpriced."
Our take: A fair summary of the title — but the video's real finding is subtler: raw cells are not bad, they are just no longer cheap enough to justify the work. When the price gap between loose cells and finished server rack batteries shrinks to a few dollars per watt-hour, the rational buyer takes the warranty. The remaining DIY buyers are people who need custom specs or simply enjoy building — and for them, prices are still workable if they shop smart.
@Andrew Fidel · 110 likes
"$889 for the cells, there's your answer. When you did the review on the $450 280Ah cells that made plenty of sense to DIY, but at twice that it is probably a pass."
Our take: Exactly the math the video lays out. At $450 for a set of 280Ah cells, DIY beat turnkey packs on price. At $889, you are paying finished-pack money for unfinished components. This is why the "is DIY cheaper?" question has no fixed answer — it depends entirely on the per-watt-hour price you can get. Always compute the cost per watt-hour before committing: if loose cells cost more than about 20-25 cents per watt-hour delivered, a server rack battery is usually the better buy.
@Alice Lu · 87 likes
"I work in the lithium battery industry and have handled many warranty cases of pre-built 12V LFP batteries. One of the most common warranty claims is the battery failing from cell mismatch or weak BMS protection."
Our take: Valuable insider perspective — and it cuts both ways. Cheap pre-built packs fail from the same root causes as bad DIY builds: mismatched cells and under-spec BMS. The lesson for buyers is to check what BMS a turnkey pack actually uses and whether the vendor matches cells before assembly. A quality manufacturer tests cells, matches them by internal resistance and capacity, and uses a BMS with real current headroom — that is the difference between a pack that lasts 10 years and one that dies in 18 months.
@Doug B · 86 likes
"The server rack batteries are an easier option and they look nice but I am not giving up on building my own battery yet. I built one 2 years ago and really enjoy maintaining it."
Our take: This is the honest middle of the debate. A DIY pack you built and understand is genuinely satisfying, and two years of trouble-free service is real evidence. Maintenance is also easier when you know every joint. The advice from the video still applies though: if you are building new, price it per watt-hour first — and if a turnkey pack is within a few dollars, the warranty probably wins. If you already own a healthy DIY pack, keeping it is a perfectly good decision.
@Ken Johnson · 83 likes
"They need to drop the price on raw cells and they would get more sales. I would love to do a DIY but the price on assembled batteries with a warranty wins out."
Our take: Agreed, and the market is heading that way — cell prices have kept falling, and a 2024-era commenter on the video notes genuine Grade A 305-320Ah cells are now available for roughly $75 each. When cells get back to that kind of pricing, DIY makes sense again for anyone who wants a custom pack. Until then, the warranty on a turnkey battery is a very reasonable premium to pay.
@ugh-meh · 83 likes
"I really love electrical DIY projects. I love the idea of putting my own battery together from scratch. But if you plan on adding actual value, the math has to work on cell pricing."
Our take: Well put. Enthusiasm alone does not make a battery economical — the per-watt-hour price does. The practical version of this: set a price threshold before you start shopping. If cells land above your threshold, buy a turnkey pack and redirect your DIY energy to something the market does not already do well, like a custom enclosure or a clever wiring layout. Value comes from choosing the right build, not from building for its own sake.
@Jim Murphy · 54 likes
"Revisiting this 2022 video in mid 2024: raw cell pricing has fallen off a cliff. Genuine grade A new cells from Alibaba are now down to about $75 US for 305-320Ah cells."
Our take: An important update that shifts the conclusion. When 305-320Ah Grade A cells reach $75, DIY becomes attractive again on price — but the channel warning from the video still stands. A direct Alibaba order at that price is only a good deal if the seller is genuinely shipping Grade A cells and honors returns. Keep the safety buffer: price per watt-hour from a distributor with a return policy, and verify cells on arrival (capacity test and internal resistance check) before building with them.

Source video: DIY Solar Power with Will Prowse — "Why are people NOT buying raw LiFePO4 cells?" (youtube.com/watch?v=ICPDTq-ePP4). Comment excerpts are quoted verbatim from the video's top comments; the original creator did not reply to these threads, so all answers are Dajiu Energy's own. Build figures are transcribed from the video's measurements.