LiPo vs NiMH RC Car Batteries

How does LiPo voltage compare to NiMH?

LiPo cells are rated at 3.7V nominal, 4.2V at full charge, and should never be discharged under load below about 3.2-3.3V per cell (some ESCs cut off closer to 3.0V). A 2-cell (2S) LiPo pack is therefore 7.4V nominal. NiMH cells are rated at 1.2V nominal, so a common 6-cell NiMH pack lands at 7.2V nominal, close enough to a 2S LiPo that the two are often described as roughly equivalent in voltage. The real-world difference shows up under load: a NiMH pack's voltage sags more as current draw increases and as the pack depletes, so a truck running on NiMH will noticeably slow down over the course of a run in a way a similarly-rated LiPo pack will not.

Which battery gives better runtime?

Runtime in minutes works out to (mAh / 1000) times 0.8 usable capacity, divided by average amp draw, times 60. A 5200mAh 2S LiPo like the HOOVO 2S 5200mAh 80C running at an average draw of 15A works out to (5.2 x 0.8 / 15) x 60, or about 16.6 minutes. A 3000mAh NiMH pack like the Tenergy 7.2V 3000mAh 6-Cell at the same 15A average draw works out to (3.0 x 0.8 / 15) x 60, or about 9.6 minutes, notably less, both because of lower capacity and because NiMH voltage sag under the same load effectively reduces usable power before the pack is technically empty. Use the LiPo runtime calculator with your actual battery and truck's typical draw for a more precise number.

Which battery is safer to charge and store?

NiMH is the simpler and lower-risk chemistry by a wide margin. It does not carry meaningful fire risk from puncture, overcharge, or short circuit the way LiPo does, and most basic chargers, including simple wall chargers, handle NiMH safely without balance-charging concerns. LiPo requires real discipline: charge in a LiPo bag on a non-flammable surface, never charge unattended, store the pack at about 3.8V per cell rather than full charge for long-term storage, and never charge a pack that has developed a puff (visible swelling), which signals internal damage and a real fire risk.

This is the main reason NiMH still shows up in entry-level and kid-oriented trucks, including some Traxxas completer packs like the Traxxas Battery/Charger Completer Flat Pack with NiMH Battery at $70.25: it removes an entire category of safety rules a parent or first-time buyer would otherwise need to learn.

Which one should you buy?

For a hobby-grade basher, crawler, or anything performance-oriented, LiPo is the practical default today, more capacity per dollar, less weight, and voltage that holds up under load. The tradeoff is real: LiPo demands a balance charger, a fireproof storage bag, and attention to storage voltage. For a first RC car, a young kid's truck, or a buyer who wants to skip the LiPo learning curve entirely, NiMH remains a legitimate, lower-risk choice, even if it means less runtime and a heavier pack. Many hobbyists start on NiMH and move to LiPo once they are comfortable with the safety routine.