BESS Container Enclosure Shells in Six Approved Sizes

What a BESS container is when you buy the shell alone

A BESS container is the steel box a battery energy storage system lives in. On this page SAMAN sells that box and nothing else. We fabricate a windowless walk in enclosure on a welded steel chassis. We line it and fit the service doors. It reaches you with the internal zones already reserved on a drawing. The cells, the racks and the power electronics arrive later, from your own supplier.

That is a narrower offer than most listings you will find, and it is deliberate. An enclosure maker cannot honestly price a battery it did not select. Energy capacity depends on cell chemistry, rack count, thermal design and the duty you are buying for. None of it follows from the length of a container, so we do not quote an energy figure anywhere on this page. We would rather publish a narrow claim we can defend than a wide one you cannot check.

What we can be precise about is the box. Six sizes are drawn and approved. Each one has a fixed footprint, a fixed rack reservation, a fixed technical bay and a published price. You can take those numbers to your integrator and check them against a real rack schedule before you commit to anything.

Where these enclosures go to work

Most of these shells end up on solar plants, in factory energy yards, on utility pads and inside outdoor power compounds. The buyer is usually a solar EPC contractor, an industrial energy manager, a utility integrator or a microgrid developer. In every case somebody else owns the battery decision, and the enclosure has to fit around it.

The pattern is consistent. A project selects its battery OEM first. Then it needs a weatherproof, serviceable structure to put that equipment in. That structure sits inside a safety exclusion zone. It wires back to a PCS and a transformer. That structure is what we build.

Site conditions change the specification more than the application does. Coastal air, industrial atmosphere, ambient range, wind and seismic inputs all feed the steel and coating decision. So does the corrosion category you are designing to. Tell us the location early and the shell can be specified for it rather than repainted later.

How container length turns into reserved rack space

Inside every size, the plan is the same. Two rack reservation zones run down the long walls and face each other. A three foot service aisle runs between them. At one end sits a technical bay for the thermal plant, the PCS interface and the service disconnect zone. A cable route is reserved along the floor.

What changes between sizes is how that length is divided. A longer box does not simply give more of everything. The two high cube variants deliberately give back rack length to win bay depth, because liquid cooling plant needs the room. That is the real trade in this range, and it is why two shells at the same price are not the same shell.

Read the table against your own rack footprint. Reserved length is not a rack count. It is the envelope we keep clear. Your OEM decides how many racks fit inside it, once anchor pattern, service clearance and thermal spacing are fixed.

The access pattern, and why it shapes your exclusion zone

Openings on a battery enclosure are placed for service and for safety, never for light. There are no ordinary windows on any wall of any size. The end wall we call End C carries a six foot double service door, centred. That is the route equipment takes in and out.

The long wall we call Wall A carries one three foot service door. It sits in the bay nearest the technical end, on five of the six sizes. It lets a technician reach the plant without opening the main doors. The 10 ft compact has no such door, so it works with one access assembly only. The opposite long wall stays blank and is reserved for ventilation and relief. The remaining end wall is kept free of ordinary doors and works as the technical service end.

• End C: one 6 ft centred double service door on every size, for equipment removal
• Wall A: one 3 ft service door in the rear bay, on all sizes except the 10 ft compact
• Wall B: no doors at all, reserved for ventilation and relief openings
• End D: technical service end, free of ordinary doors, with the interface bay behind it
• All four walls: zero ordinary windows, on every size in the range

Plan your exclusion zone and your cable trench around that pattern before the plinth is cast. Door swings, relief discharge direction and the clear working space a technician needs are all decided by it. Moving a door after fabrication is an engineering change, not a site adjustment.

Where our scope ends and yours begins

This is the part most suppliers leave vague, so here it is in a table. Everything in the first column is inside the published price. Everything in the second stays with you or your integrator unless a signed quotation says otherwise. Nothing moves between the columns without a written change.

We publish this because an enclosure quotation and a system quotation are not comparable numbers. A price that includes racks, a PCS and a cooling skid will always look larger. Compare like with like, and ask any supplier to show you the same split before you weigh two offers against each other.

Options exist within our scope. Coating category, lining specification, opening reinforcement, gland plate provision and internal partition arrangement can all be varied against the approved GA. Anything that changes an opening, an equipment load or a utility entry has to be frozen before we release the shell for fabrication.

Steel, coating and corrosion duty

The base is an equipment chassis rather than an office floor. It runs a minimum 150x75x5 mm perimeter, or an engineered equivalent. Cross members and rack support rails are set to the coordinates your racks actually use. Design load is project specific and can be many times a normal floor loading, so it is checked against your declared rack footprint before fabrication.

The envelope is a weatherproof non combustible metal shell, typically 1.6 to 2.0 mm profiled or flat steel, or a tested non combustible panel system. The roof is a sealed weather roof with positive fall and sealed service penetrations. Wall insulation is normally 75 to 100 mm mineral wool or an approved tested system, with roof insulation around 100 mm.

Coating is chosen for the exposure you are in, not for a catalogue default. Inland, industrial, coastal and marine duty each call for a different system, and internal steel is protected before equipment goes in. We record dry film thickness, holiday testing and touch up rather than claiming a fixed life we cannot support.

Thermal, gas relief and fire: what we reserve and what you supply

The enclosure reserves the space and the routes. It does not supply the systems. Cooling capacity, airflow path, condensate, purge mode and fire interlocks are designed by your BESS integrator against real heat load data. We build the bay, the penetrations and the mounting provision that design needs.

Openings for pressure relief, deflagration venting, louvres or exhaust come from an approved fire and explosion hazard study. Free area, opening pressure, discharge direction and the exclusion zone around them are set by your fire engineer and your OEM. We will cut and frame what that study specifies, and we will not invent it.

Internal linings and compartment barriers are specified by tested assembly rather than by board name. Fire resistance is a property of a tested build up, not of a material on its own. Your strategy may call for a rated barrier around the battery, electrical or control zones. Name it in the enquiry, so the right assembly gets priced.

What we need before fabrication can start

An enquiry that carries these five blocks comes back as a specific quotation. One that carries only a size comes back with assumptions attached, and assumptions are what later become variations. Send the five blocks together if you can. A partial enquiry still gets a reply, but it gets a range instead of a price.

• Selected battery OEM, rack and module data, and the usable energy or power duty you need
• Site location, ambient temperature range, corrosion category and seismic or wind inputs
• Thermal management concept, heat rejection data and equipment service clearances
• Fire strategy, gas and pressure relief basis, access and egress and authority requirements
• Electrical single line, cable entry schedule, earthing philosophy and auxiliary loads

If some of it is still open, say so. We will quote the base shell against the approved GA and mark the dependent items as options. Your budget then stays honest while the engineering settles, instead of carrying a number that has to move later.

Site readiness, foundation and placement

These shells land on a prepared plinth, not on soil. The plinth has to be level. It must carry the installed system mass, not the empty shell. Detail your hold down and earthing provision into it before it is cast. Drainage matters too, because a battery enclosure should never sit in standing water.

Access decides more than most buyers expect. A 40 ft unit needs a straight approach and turning room for the trailer. It also needs a crane position that still works on rack delivery day. If your yard cannot offer that, the 30 ft modular shell is often the better answer even where the area would allow a longer one.

Leave the clear working space the maintenance plan needs on every side. Leave the separation distance your fire strategy calls for between one shell and the next. Both are cheaper to allow for now than to retrofit around a commissioned system.

What an enclosure supplier can and cannot certify

We can certify our own work. That means dimensional inspection, weld and bolt condition, coating, sealing, earth continuity, door and interlock function, and a dispatch record for the shell we built. Those checks belong to us and we stand behind them.

We cannot certify a battery system we did not supply. UL 9540A, IEC 62619 and IEC 63056 are project compliance inputs on this page, and nothing more. Conformity is claimed only where valid OEM or laboratory evidence exists. That evidence attaches to the battery system and its integrator, not to an empty steel box.

Warranty follows the same line. The enclosure warranty is separate from the warranty on cells, racks, BMS, EMS, PCS, HVAC, fire systems and site integration. Its period and its scope are confirmed in your quotation. SAMAN POS India Private Limited operates ISO 9001:2015, ISO 14001:2015 and ISO 45001:2018 certified management systems. We build in our own units at Bengaluru and Greater Noida.

A battery enclosure is not a container office

Buyers sometimes arrive here from our office pages, so the difference is worth stating. An office is glazed, insulated for comfort, fitted out and floored for people. This is none of those things. You may want a real freight shell converted into a working office. In that case a shipping container office cut from a genuine ISO hull is the page you need.

There is one honest similarity. Like the value line container office cabin, these shells are built from scratch on a welded steel frame. They are not cut out of a used freight box. That gives us control over member sizes, opening reinforcement and floor loading. It matters far more when a floor carries racks than when it carries desks.

Questions buyers ask before they order

How much energy will a 20 ft BESS container store?

We cannot tell you, and neither can anyone selling you only a box. Stored energy depends on cell chemistry, rack count, usable depth of discharge and the thermal design. Two 20 ft enclosures with different racks inside them hold very different amounts. Your battery OEM gives you that figure.

Is the price on this page for a complete battery system?

No. It is a budgetary price for the enclosure and the interfaces listed on its drawing. Cells, racks, BMS, PCS, transformer, switchgear, cooling, fire systems, cabling, foundations and commissioning all sit outside it unless a signed quotation says otherwise. That split is deliberate. It keeps our number checkable against a drawing, rather than bundled into a figure nobody can take apart.

Can you build a size that is not one of the six?

The six on this page are drawn, approved and priced, so they quote fastest and carry the least risk. Other envelopes are possible as a project item. They need their own drawing and their own price, and they will not follow the ladder shown here.

Why do the two 20 ft shells cost the same?

Because they share a footprint and an area band. The high cube is a foot taller and splits its length differently. It gives 12.5 ft of rack per side against 14 ft, and a 5.5 ft bay against 4 ft. You are choosing layout and height, not paying for extra area.

Do the enclosures stack?

Not unless calculations and certification explicitly cover it. A structure that resembles a freight container is not automatically stackable or CSC compliant. Corner details, post sections and opening reinforcement all need structural substantiation first. Ask the question early if stacking is part of your layout. It changes the frame, not just the paperwork.

Can the enclosure be lifted with the batteries already installed?

Only when your BESS OEM, the transporter and a structural engineer all approve that shipped condition. Otherwise the shell moves empty, or in a partial build condition that is defined in writing before dispatch. Plan for an empty lift by default. It keeps the transport case simple and the insurance position clear.

What is reserved for cable entry?

A cable route is reserved along the floor and gland plate provision is set out on the approved GA. Final trench detail, entry side, bend radius and sealing after your cables land are project engineering, and they are frozen with you before fabrication.

Are these prices final?

They are budgetary planning values from our workbook, before 18 per cent GST is added where shown. A signed quotation against your rack schedule, site inputs and fire strategy is the number that governs supply. Treat the ladder on this page as a planning tool. It is accurate enough to budget with, and it is not a substitute for a quotation.