Buying Guide
2 Best RV Battery For Fifth Wheel in 2026: A Practical RV Guide
Two Redodo LiFePO4 Group 31 batteries for fifth wheel RVs, 165Ah and a self-heating 100Ah, compared on energy, price per Wh and cold charging.
By Hardcastle's RV Editors
10 min read2 products evaluated
Fifth wheels usually have roomier battery trays than small trailers and heavier house loads: a residential fridge, slide-outs, an inverter. That makes capacity and cold behavior the key decisions. Both picks here are Redodo LiFePO4 batteries in the same Group 31 case, so fit is identical and the choice comes down to energy versus cold-weather charging.
Hardcastle’s RV field notes
The Rig Fit Check
A quick way to connect the shortlist to the space, workload and ownership details that matter after the box arrives.
- Start with the job
- Redodo 12V 165Ah LiFePO4 Battery leads this shortlist for Residential fridge and inverter loads. Use that fit as a reference point, then compare the alternatives against your own space and workload.
- Specs that separate the picks
- The first details to compare are 12.8V 165Ah, 2112Wh, 12.8V 100Ah, 1280Wh. Confirm the exact model and included components before ordering.
- Trade-off to plan for
- Charging stops at 32°F with no heater
The Practical Shortlist
A road-tested-thinking look at 2 options, organized around the job each one suits best.
Best Overall
Redodo 12V 165Ah LiFePO4 Battery
Residential fridge and inverter loads
Our take Check price for Redodo 12V 165Ah LiFePO4 Battery (opens in a new tab)
Best for Cold Weather
Redodo 12V 100Ah LiFePO4 Battery
Winter fifth wheel stays
Our take Check price for Redodo 12V 100Ah LiFePO4 Battery (opens in a new tab)
| Pick | Best for | Key spec | Price |
|---|---|---|---|
| Residential fridge and inverter loads | 12.8V 165Ah, 2112Wh | Check price for Redodo 12V 165Ah LiFePO4 Battery (opens in a new tab) |
| Winter fifth wheel stays | 12.8V 100Ah, 1280Wh | Check price for Redodo 12V 100Ah LiFePO4 Battery (opens in a new tab) |
Why Each Pick Made the Cut
Best Overall1 of 2
Redodo 12V 165Ah LiFePO4 Battery on Amazon (opens in a new tab)
The strongest case for Redodo 12V 165Ah LiFePO4 Battery is 2112Wh in one Group 31 case.
Best for
- Residential fridge and inverter loads
Why it made the shortlist
For Residential fridge and inverter loads, this is one of the more relevant configurations in the shortlist. The documented setup centers on 12.8V 165Ah, 2112Wh, 165A BMS, Bluetooth, group 31, IP65 case.
Its case starts with 2112Wh in one Group 31 case. Its 12.8V 165Ah, 2112Wh specification sits at the same documented level as the comparable picks in this 2-product comparison. Treat the battery platform and included charger as part of the fit, not just the headline number.
The trade-off worth checking first is charging stops at 32°F with no heater. Confirm whether the battery and charger are included with the exact package. Check platform compatibility and published runtime against the area or workload you need to cover.
Key dimensions & specs
- 12.8V 165Ah, 2112Wh
- 165A BMS, Bluetooth
- Group 31, IP65 case
Pros
- 2112Wh in one Group 31 case
- 165A BMS supports up to 2112W output
- Bluetooth lets you check battery status from your phone
Cons
- Charging stops at 32°F with no heater
- Costs $429.99, a bigger upfront spend
Best for Cold Weather2 of 2
Redodo 12V 100Ah LiFePO4 Battery on Amazon (opens in a new tab)
Redodo 12V 100Ah LiFePO4 Battery is the better fit when winter fifth wheel stays.
Best for
- Winter fifth wheel stays
Why it made the shortlist
The intended use case is Winter fifth wheel stays. The documented setup centers on 12.8V 100Ah, 1280Wh, self-heating, -4°F charging, group 31, 23.32 lb.
What separates it on paper is self-heating allows charging down to -4°F. Its 12.8V 100Ah, 1280Wh specification sits at the same documented level as the comparable picks in this 2-product comparison. Treat the battery platform and included charger as part of the fit, not just the headline number.
Before committing, account for heating needs at least 10A charging current. Confirm whether the battery and charger are included with the exact package. Check platform compatibility and published runtime against the area or workload you need to cover.
Key dimensions & specs
- 12.8V 100Ah, 1280Wh
- Self-heating, -4°F charging
- Group 31, 23.32 lb
Pros
- Self-heating allows charging down to -4°F
- Weighs 23.32 lb in a Group 31 case
- Can expand to 4 parallel and 4 series
Cons
- Heating needs at least 10A charging current
- 1280Wh runs out fast with an inverter
How We Built This Shortlist
Each pick was assessed across 4 criteria weighted for real-world use.
- Usable energy
- We compared rated watt-hours and BMS discharge limits against fifth wheel loads.
- Cold behavior
- We checked low-temperature charge limits and heating.
- Fit
- We checked case size, group and terminals.
- Price per Wh
- We calculated cost per watt-hour.
What Matters Before You Choose an RV Battery For Fifth Wheel
Key buying criteria so you get the right fit the first time.
Rated energy in watt-hours
Watt-hours equal volts times amp-hours, so 12.8V x 165Ah is about 2112Wh. A residential fridge draws roughly 1 to 2 kWh a day. Compare Wh to daily use.
BMS continuous discharge
The BMS cuts power above its limit. The Redodo 165Ah lists 165A, about 2112W. Add your inverter and appliance loads.
Cold charging behavior
LiFePO4 should not charge below 32°F. The Redodo 100Ah Heated charges to -4°F with 10A of charging current. Check charge limits on the listing.
Group size and tray fit check
Both picks share a Group 31 case of 13 x 6.77 x 8.5 inches. Measure your tray before ordering. A tray that is even half an inch short forces cable bends that stress the M8 terminals.
Parallel and series expansion rules
Both list up to 4 in parallel and 4 in series. Use matching batteries and confirm wiring. Mixing a 165Ah and a 100Ah battery in one bank is a bad idea because uneven voltage and resistance cause imbalance.
Match an RV Battery For Fifth Wheel to Your RV
By Camping Season
| Your situation | Recommended pick | Why |
|---|---|---|
| Year-round with freezing nights | Redodo 100Ah Heated | Heating allows charging down to -4°F. |
| Warm weather, big loads | Redodo 165Ah | 2112Wh runs a fridge and inverter longer. |
| Boondocking in mild climates | Redodo 165Ah | Best price per Wh. |
| Shore power mostly | Redodo 100Ah Heated | Lower cost and heating at the pedestal. |
Scroll sideways to see every column.
By Budget
| Budget | Recommended pick |
|---|---|
| $270 to $280 | Redodo 100Ah Heated |
| $420 to $430 | Redodo 165Ah |
Capacity vs Cold Charging
- More capacity
- Redodo 165Ah delivers 2112Wh but stops charging at 32°F.
- Self-heating
- Redodo 100Ah Heated charges to -4°F but holds 1280Wh.
Default to the 165Ah unless you camp below freezing.
By Budget
| Recommended | Recommended pick |
|---|---|
| Under $300 | Redodo 100Ah Heated |
| Over $400, maximum energy | Redodo 165Ah |
For Residential Fridge Fifth Wheels Specifically
- Look for
- At least 2000Wh and a BMS rated above your inverter draw.
- In this comparison
- Redodo 165Ah provides 2112Wh and a 165A BMS.
When to Spend More
- Spend more if
- if you run an inverter, the $429.99 Redodo 165Ah gives 832Wh more than the Redodo 100Ah Heated.
- Save if
- if you camp in freezing weather with shore power, the $279.99 Redodo 100Ah Heated costs $150.00 less.
Before You Bring One Home
Which Redodo is better for a fifth wheel?
The 165Ah suits big loads. The 100Ah Heated suits freezing weather.
Does the 165Ah heat itself?
No. The listing describes low-temperature protection that stops charging at 32°F.
How much energy do I need?
Add up daily watt-hours of your fridge, lights and inverter loads. Compare that to 2112Wh and 1280Wh.
Do both fit a Group 31 tray?
Both list a 13 x 6.77 x 8.5 inch case. Check terminal clearance.
Bottom Line
Best overall: Redodo 12V 165Ah LiFePO4 Battery — best overall pick in this roundup. See the full verdicts above for every pick, with pros, cons and who each one suits.
Browse all rv battery for fifth wheel on Amazon — Prime-eligible options with current pricing.