The first time I priced out a lithium conversion for my own van, I made the classic mistake: I multiplied one battery’s sticker price by four and called it done. Then the fuse block, the busbars, the new converter and three hours on the phone with a battery manufacturer’s support line happened, and my “budget” was off by almost $600.
So let’s do this properly. I’m going to walk through every piece of a real lithium battery bank cost, using actual 2026 street prices from brands people in this community actually buy: Battle Born, Li Time, Ampere Time, Renogy and a few budget options. No made-up numbers.
The quick version
- A single 100Ah lithium battery runs $250 to $950 depending on brand, with $350 to $550 being the realistic middle for a reputable one.
- A typical 200Ah usable bank (two 100Ah batteries) lands between $700 and $1,900 before install parts.
- Supporting hardware (fuses, busbars, cable, a battery monitor) usually adds $200 to $500.
- Charging upgrades, like a new converter or DC-DC charger, can add $150 to $600 if your current gear is not lithium-compatible.
- DIY labor is free but costs time; professional installs run $800 to $2,500 depending on system complexity.
Pricing the batteries themselves
This is where most of the money goes, and where the range is widest. A 12V 100Ah drop-in lithium battery from a budget import brand can be had for $250 to $320. Ampere Time and similar mid-tier brands usually sit around $300 to $400 for the same capacity. Battle Born, the brand most RV dealers install at the factory, prices its 100Ah battery around $900 to $950.
That is not Battle Born overcharging you. Their batteries use a more conservative BMS, better documented cycle life, and a warranty and support team that actually answers the phone. Li Time sits in between, often $350 to $450 for a 100Ah unit with Bluetooth monitoring built in.
Tip: Price per usable amp-hour, not per battery. A $300 lead-acid-replacement lithium battery that only delivers 80Ah safely is a worse deal than a $380 battery rated for a true 100Ah at 100% depth of discharge. Check the spec sheet, not just the label. If you are unsure how to read one, our guide on reading a lithium battery spec sheet walks through exactly what to look for.
What a full bank actually costs by size
Most vans run 200 to 300Ah usable, most Class A and fifth wheels run 300 to 600Ah. Here is a rough matrix based on real listed prices as of mid-2026.
| Bank size (usable Ah) | Budget brand | Mid-tier (Li Time, Ampere Time) | Premium (Battle Born) |
|---|---|---|---|
| 100Ah | $250-$320 | $350-$450 | $900-$950 |
| 200Ah | $550-$700 | $700-$900 | $1,800-$1,900 |
| 300Ah | $800-$1,050 | $1,050-$1,350 | $2,700-$2,850 |
| 400Ah | $1,050-$1,400 | $1,400-$1,800 | $3,600-$3,800 |
Notice the price gap widens fast as banks get bigger. That is why a lot of full-timers running 400Ah+ banks mix strategies: some go all Battle Born for the warranty peace of mind, others stack four mid-tier batteries and pocket the $1,800 difference. If you are still deciding how many amp hours actually fits your usage, work backward from your daily draw first, our piece on figuring out how many amp hours you need will save you from oversizing (and overspending).
The supporting hardware nobody budgets for
Here is the part that bit me on my own build. A lithium battery bank is not just batteries sitting in a box.
- Class T or MRBF fuse and holder: $30-$90
- Marine-grade battery cable (2/0 or 4/0 depending on inverter size): $60-$180 for a typical run
- Busbars (positive and negative): $30-$70
- Battery monitor with shunt (Victron SmartShunt, Renogy DCC, etc.): $80-$180
- Main battery disconnect switch: $25-$60
- Mounting tray or box, hold-downs: $20-$60
Add it up and you are looking at $250 to $600 in parts most people do not think about until they are standing in a store aisle. This is on top of the batteries. A mistake I see constantly on forums: someone posts “lithium cost me $1,200 more than I expected,” and it turns out they priced the batteries but forgot the fuse, cable, and monitor entirely.
Charging equipment: the real budget-breaker
This is the single biggest wildcard in any lithium battery bank cost estimate. If your RV came with an older WFCO or Progressive Dynamics converter built for lead acid, it may not charge lithium correctly at all, or it will charge it to a lower voltage than the BMS wants, leaving capacity on the table.
A lithium-compatible replacement converter, like a Progressive Dynamics PD9200 series with the lithium profile, runs $180 to $350 installed yourself. If you are also charging from the alternator while driving, a DC-DC charger (Victron Orion-Tr Smart or Renogy DCC50S) adds another $150 to $300 plus wiring.
Warning: Do not skip this step to save money. Charging lithium with the wrong profile is not just inefficient, it can trip the BMS repeatedly or, in worse cases, undercharge the battery for years without you noticing a problem until capacity mysteriously drops. See Victron’s lithium battery documentation for the charge voltages your equipment should actually be hitting.
DIY versus professional installation cost
If you are comfortable with a multimeter and a crimper, DIY installation costs you nothing beyond the parts above and maybe a $40 crimping tool you will reuse forever. A weekend of work, honestly, for most single-battery swaps.
Professional installation at an RV shop or marine electrician typically runs $800 to $2,500 depending on region and complexity. Shops in high-cost areas like coastal California or the Pacific Northwest often bill $125 to $175 an hour, and a proper lithium conversion with converter replacement can take 8 to 15 hours. That labor bill alone can exceed what the batteries cost.
If you are debating whether to buy a pre-wired drop-in unit versus building your own bank from bare cells, that decision changes your cost math significantly, our comparison of drop-in lithium versus building your own covers where each approach saves or costs you money.
A real scenario: what I’d budget for a Sprinter van build
Say you are converting a Sprinter van to full-time living, targeting 300Ah usable at 12V, keeping your factory converter as backup but adding solar and a DC-DC charger. Here is a realistic total using mid-tier batteries.
| Item | Estimated cost |
|---|---|
| 3x 100Ah Li Time or Ampere Time batteries | $1,050-$1,350 |
| Fusing, busbars, cable, disconnect | $250-$450 |
| Battery monitor with shunt | $100-$180 |
| DC-DC charger (Victron Orion-Tr Smart 30A) | $220-$280 |
| Wiring, fuses, terminal lugs for DC-DC run | $80-$150 |
| Total (DIY labor) | $1,700-$2,410 |
Compare that to a similar 300Ah AGM lead-acid bank, which might run $600 to $900 for batteries but weighs three times as much, delivers roughly half the usable capacity, and needs full replacement in 3 to 5 years instead of 10+. Whether that trade makes sense for you is really a question of how long you plan to keep the rig and how much you value weight and space, which is exactly what our deeper look at whether lithium is worth it digs into with the full lifetime cost math.
Ways to bring the number down without cutting corners
You do not have to spend Battle Born money to get a safe, reliable bank. A few honest ways to trim cost.
- Buy mid-tier brands with a documented BMS and at least a 5-year warranty rather than the cheapest unbranded option on Amazon.
- Reuse your existing converter if it already has a lithium charge profile, many 2020-plus rigs already do.
- Skip the DC-DC charger initially if you rarely drive between charges and rely mainly on solar and shore power, adding it later is straightforward.
- Buy cable and lugs from an electrical supplier rather than a marine store markup, the wire itself is often 30 to 40% cheaper.
What you should never cut is the fuse. A $40 Class T fuse holder protects thousands of dollars of battery and wiring from a short circuit, and per ABYC wiring standards, proper overcurrent protection sized to your cable is not optional if you want the system to actually be safe.
Price this out for your own rig before you buy anything. Write down your target amp hours, price batteries from two or three brands, then add the hardware list above honestly instead of assuming your existing converter and cable will just work. That single hour of planning is what separates a $1,800 lithium upgrade that just works from a $2,600 one with surprise expenses halfway through the install.
