Batteries
RC car battery sizes explained
A battery that is the wrong size is either the wrong voltage, the wrong shape, or the wrong amount of punch. All three are stamped on the label, and all three are easy to read once you know which number is which.
By Ryder M. · Published October 6, 2026 · Last reviewed
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For a 1/10 scale RC car, the standard answer is a 2S LiPo pack of 3000 to 5000mAh, and for a 1/16 or 1/18 car a 2S pack of 1500 to 2200mAh. But "size" means four different numbers on an RC battery, and getting any one of them wrong produces a different problem: the wrong cell count is the wrong voltage and can destroy the speed control, the wrong capacity is the wrong run time, the wrong C rating means the car feels flat under load, and the wrong physical dimensions means the pack simply does not go into the tray.
Short version: match the cell count to what the car's manual states — almost always 2S for a 1/10 car, 3S if the manual allows it. Then buy the largest capacity that physically fits the battery tray, with a C rating of 50C or above, in the connector the car already uses.
The four numbers on the label
| Number | What it looks like | What it decides | How to choose |
|---|---|---|---|
| Cell count | 2S, 3S, 6S | Voltage — 3.7V per cell nominal, so 2S is 7.4V | Whatever the car's manual states. Never more. |
| Capacity | 3000mAh, 5000mAh | Run time, and weight | The biggest that fits the tray |
| C rating | 50C, 100C | How hard the pack can be drained without sagging | 50C or above for a basher; higher for racing |
| Dimensions | 139 x 47 x 25 mm | Whether it fits at all | Measure the tray, then compare against the listing |
| Connector | EC3, Deans, Traxxas, XT60 | Whether you can plug it in | Match the car, or buy an adapter |
Cell count is the one that matters most
2S means two cells in series: 7.4 volts nominal, 8.4 fully charged. 3S is three cells, 11.1 volts. 6S is six, roughly 22 volts. Voltage is what sets the car's speed, and it is also the number that can break things — a speed control rated for 2S will not survive 3S, and a motor geared for 2S will run hot on 3S even where the electronics cope. The car's manual states what it accepts, and that figure is the constraint. 2S vs 3S LiPo is the page for anyone deciding between the two.
The practical mapping by scale is consistent enough to be useful, as long as you still check the manual.
| Car scale | Usual cell count | Usual capacity | Why |
|---|---|---|---|
| 1/24 crawler | 2S | 380-800mAh | Tiny tray, tiny motor, walking pace |
| 1/18 crawler or basher | 2S | 750-2200mAh | Small tray; capacity is limited by space, not need |
| 1/16 truck | 2S or 3S | 1500-2200mAh | 3S only where the listing allows it |
| 1/10 car or truck | 2S, sometimes 3S | 3000-5000mAh | The standard hobby size; trays are generous |
| 1/8 truck | 4S or 6S | 5000mAh and up, often two packs | High voltage, high current, long runs |
Capacity: bigger is better until it does not fit
Capacity in milliamp-hours is simply how much energy the pack holds, and it maps almost directly to run time: a 5000mAh pack runs roughly two-thirds longer than a 3000mAh pack in the same car. The limits are physical and financial. A bigger pack is longer, taller and heavier, and the battery tray is a fixed size — this is why measuring the tray before buying is worth the two minutes. Added weight also changes the car slightly, making it a little more planted and a little harder on the suspension.
C rating, and why 50C is enough
The C rating describes how hard the pack can be drained. Multiply the C rating by the capacity in amp-hours to get the claimed maximum continuous current: a 5000mAh 50C pack claims 250 amps, which is comfortably more than a 1/10 basher ever draws. A pack with too low a rating sags under throttle and the car feels flat and gets hot. In practice anything from 50C upward is fine for a basher, and the very high numbers on budget packs are marketing rather than measurement. Buying a reputable 50C pack beats buying a no-name 150C one.
Connectors: the last thing to check
A perfectly sized pack with the wrong plug on it will not connect to the car. Traxxas uses its own connector, and the rest of the hobby is split between EC3, Deans and XT60. Adapters exist, work fine and add a little resistance and a little clutter. RC car battery connectors identifies each type by sight so you can order the right one the first time.
The packs we recommend
| # | Product | Best for | Score | Price |
|---|---|---|---|---|
| 1 | Gens Ace 2S LiPo batteryThe brand most people settle on once they have been burned by a cheap pack that puffed after a month. | The reliable default | 8.7 | |
| 2 | Zeee 2S LiPo batterySold in twos for about what one premium pack costs — the reason so many garages have a stack of them. | Two packs, low spend | 8.1 | |
| 3 |  Ovonic 2S LiPo batteryThe sensible middle: better built than the bargain packs, cheaper than the premium ones. | Middle ground | 8.4 | |
| 4 | Traxxas Power Cell 2S LiPo batteryThe no-thinking-required upgrade if the car in question is a Traxxas. | Traxxas owners | 8.6 |
Illustrative photo — not this exact model.
#1 · The reliable default
Gens Ace 2S LiPo battery
The brand most people settle on once they have been burned by a cheap pack that puffed after a month.
8.7/10our score for this use
LiPo is the standard rechargeable battery chemistry for RC cars: lighter than the older NiMH type and it holds its power right up to the end of the run rather than gradually fading. 2S means two cells — the size most 1/10 cars take.
What it does well
- Consistent pack-to-pack quality, which is the whole argument for paying more for a battery
- Holds voltage under load, so the car feels the same on lap ten as on lap one
- Sold in all the common connector types and sizes
What it does badly
- Costs more than the budget brands for capacity you can measure but may not notice
- Like all LiPo packs it must be stored at partial charge, not full, or it degrades
- Needs a balance charger — it cannot be charged with the wall plug from a toy car
Illustrative photo — not this exact model.
#2 · Two packs, low spend
Zeee 2S LiPo battery
Sold in twos for about what one premium pack costs — the reason so many garages have a stack of them.
8.1/10our score for this use
The budget end of the LiPo market, usually sold as a two-pack. For a gift where the goal is more driving time rather than maximum performance, two adequate batteries beat one excellent one.
What it does well
- Two-packs at a price that makes a spare battery an easy decision
- Perfectly adequate for bashing, which is what most of these cars do
- Widely stocked in the common sizes
What it does badly
- Pack-to-pack consistency is not at the level of the premium brands
- They tend to age faster if they are stored fully charged — which beginners do
- Not the choice for racing
Illustrative photo — not this exact model.
#3 · Middle ground
Ovonic 2S LiPo battery
The sensible middle: better built than the bargain packs, cheaper than the premium ones.
8.4/10our score for this use
A mid-priced LiPo brand that has built a reputation for reliability without the premium price. For a car that gets used on weekends rather than raced, this is the tier that makes sense.
What it does well
- Noticeably better built than the cheapest packs on the shelf
- Widely available in the common sizes and connectors
- Good value if you want two packs instead of one premium pack
What it does badly
- Not the last word in performance if the car is being raced
- Quality is consistent but not at the level of the top-tier brands
- Still requires a proper balance charger
Illustrative photo — not this exact model.
#4 · Traxxas owners
Traxxas Power Cell 2S LiPo battery
The no-thinking-required upgrade if the car in question is a Traxxas.
8.6/10our score for this use
Traxxas' own LiPo packs carry an iD chip that tells a Traxxas charger exactly what the battery is, so there is nothing to set and nothing to get wrong. For a gift recipient who has never charged a LiPo, that matters more than a few percent of performance.
What it does well
- The iD system removes the single most intimidating part of LiPo ownership
- Fits Traxxas battery trays without adapters or foam packing
- Available at any shop that stocks Traxxas
What it does badly
- Costs more than an equivalent third-party pack
- The iD advantage only applies with a Traxxas charger
- Same LiPo storage rules apply — it still needs care
Specifications from Traxxas' batteries and chargers range.
How we assessed this
From the four numbers printed on every pack and what each one physically determines, then cross-checked against the configurations the manufacturers themselves specify for the cars on this site — Traxxas' recommendation of two 5000mAh 3-cell packs for the Sledge, and the 750mAh pack it includes with the TRX-4M, are both from its own product pages. We do not test these products first-hand; our methodology page explains what that means.