Manufacturer connection demonstration on a wooden bench, not a recommended charging station. Do not read the pictured surface or missing containment as safety guidance; follow the exact battery and charger manuals.
Horizon Hobby (photographer not identified) · Manufacturer copyright; permission required before public release
Photo credit & source ↗From the September 2026 research edition. Product details and prices are dated source records; confirm the exact model and manual before buying or making changes.
Two major ready-to-run RC brands both push their own "smart" battery systems. Traxxas has iD, and Horizon Hobby, whose brands include ARRMA, Losi and Spektrum, has Spektrum Smart. Both promise the same basic thing: plug the pack in, and the charger knows what it is dealing with.
Under the hood, though, the two systems work differently, and the differences matter when you buy a charger or want to share batteries across brands. Spektrum's second-generation (G2) Smart packs in particular change the rules about which chargers you can use.
This post explains how each system works, based on what Traxxas and Horizon publish. It also covers the lock-in trade-offs and what the matching chargers cost at list price as of September 17, 2026.
Key takeaways
- Traxxas iD: an iD charger "instantly recognizes the pack's type, cell count, and capacity" and sets the charge for you.
- Spektrum Smart G2: the pack has its own balancing and self-discharge circuit, no balance connector, and a chip that stores pack data. By default it drops to storage voltage (3.90 V per cell) after 72 hours.
- G2 Smart packs require a Spektrum Smart charger with G2 firmware. Older G1 Smart packs have balance leads.
- Spektrum Smart chargers can charge "nearly any RC hobby battery," so the charger is flexible even though G2 packs are not.
- Traxxas EZ-Peak Live chargers list at $119.95 (4S) and $199.95 (dual). Spektrum Smart chargers range from $15.99 to $319.99 on Horizon's list.
How Traxxas iD works
Traxxas's iD charger guide, published in March 2023, describes the core feature simply: when you plug an iD battery into an iD charger, "the charger instantly recognizes the pack's type, cell count, and capacity. The optimum settings are input for you."
In practice, that helps you avoid basic setup errors such as picking the wrong chemistry, cell count or current. Traxxas's pages we reviewed do not go into more detail on the internal mechanism, so we will not speculate about it.
iD covers NiMH as well as LiPo. The Slash 2WD XL-5 with battery, for example, includes a 3000 mAh 8.4 V NiMH iD pack and a 4-amp USB-C charger. The Mini Maxx BL-2s includes a 3500 mAh 2S LiPo and a 2-amp USB-C iD charger.
Traxxas iD chargers
| Model | Max current | LiPo cells | Notes | List price |
|---|---|---|---|---|
| 2970 EZ-Peak Plus 3S | 4 A | Up to 3S | Charges 5–8 cell NiMH | Not captured |
| 2972 EZ-Peak Dual 3S | 8 A | Up to 3S | Dual; 5–8 cell NiMH | Not captured |
| 2981 EZ-Peak Plus 4S | 8 A | Up to 4S | 5–8 cell NiMH | Not captured |
| 2971 EZ-Peak Live 4S | 12 A | 2–4S | 100 W; Bluetooth app monitors up to 4 chargers; one-button storage charge | $119.95 |
| 2973 EZ-Peak Live Dual | 26+ A total | 2–4S | 200 W; 1–16 A per side; "MAXX Charge" mode; 2 A USB port | $199.95 |
Traxxas also sells bundles. The 2997 Dual 4S Completer includes two 2890X 6700 mAh 4S 25C iD packs and a 2973 charger for $499.95.
Traxxas safety notes that still apply
Smart recognition does not remove the basic rules. Traxxas says to use only a LiPo balance charger, to charge LiPo in a fire-retardant or fireproof container, and to keep the ESC's Low-Voltage Detection on. Traxxas ESCs with LVD warn below 3.2 V per cell. Traxxas also warns that over-discharging an iD LiPo "will cause irreparable damage and may cause battery failure."
How Spektrum Smart works
Horizon Hobby's Smart G2 Battery and Charger FAQ describes a more involved system in which much of the intelligence lives in the battery itself.
Inside a G2 Smart pack
- Built-in balancing and self-discharge. G2 packs have a "very fast, integrated proprietary self-discharge and cell balancing circuit."
- No balance lead. The pack balances through a data wire in the connector instead of a separate balance plug.
- A memory chip. It stores the pack's parameters and history.
- Temperature monitoring. The pack slows down charge or storage events to stay in a safe temperature range.
- Automatic storage. A fully charged pack left unused for 72 hours discharges itself to 3.90 V per cell by default. You can change the time and voltage, or turn the feature off, with a Smart charger or checker.
- 1C default charging. Smart batteries charge at 1C by default. Some packs allow more. Spektrum rates its SPMX53S30 3S 5000 mAh pack for up to 5C charge.
That auto-storage feature is a real convenience, because it handles storage for packs you forget to put in storage mode yourself. Note that Spektrum's 3.90 V default is a little higher than the 3.8 V per cell in Horizon's own TRI LiPo safety sheet, a reminder that storage targets vary by source.
The connectors: IC3 and IC5
Spektrum's IC3 and IC5 connectors add a data pin that carries Smart telemetry. We did not find a Spektrum-published amp rating for either connector. A retailer chart (EuroRC) lists IC5 at 120 A, but that is not a maker figure. Spektrum sells adapters, such as one for an IC5 battery to an IC3 device.
Compatibility: the G1 vs. G2 split
According to Horizon's FAQ:
- G2 Smart packs require a Spektrum Smart charger with G2 firmware. Spektrum's product page for the SPMX53S30 also says G2 packs are "not compatible with non-Smart chargers."
- G1 Smart packs have balance leads and do not have that requirement.
- Spektrum Smart chargers can charge "nearly any RC hobby battery," not only Spektrum packs.
An example G2 pack is the SPMX53S30 Smart G2 3S 5000 mAh 30C with IC5 connector, listed at $74.99 and 430 g. Spektrum labels it 11.1 V and 55.5 Wh.
Spektrum Smart chargers
List prices on Horizon Hobby's Spektrum charger page:
| Model | Output | List price |
|---|---|---|
| S10 G2 USB-C | USB-C | $15.99 |
| S22 G2 | 20 W | $23.99 |
| S160 (IC3 or IC5) | 60 W | $32.99 |
| S100 USB-C | 100 W | $34.99 |
| S220 | 2 × 20 W | $44.99 |
| S155 G2 | 55 W | $69.99 |
| S1100 G2 | 1 × 100 W | $124.99 |
| S250 | 2 × 50 W | $129.99 |
| S1200 G2 | 1 × 200 W | $179.99 |
| S2100 G2 | 2 × 100 W | $199.99 |
| S450 G2 | 4 × 50 W | $299.99 |
| S2200 G2 | 2 × 200 W | $319.99 |
Only some models include "G2" in their names. If you use G2 packs, confirm G2 support on the specific charger's product page. The flagship S2200 G2 lists 200 W per channel (or 380 W on one channel), 0.1–20 A, 1–6S lithium chemistries, NiMH and lead-acid support, and both IC3 and IC5 outputs.
Several Horizon starter bundles include Smart gear. The ARRMA Gorgon bundle ($189.99) comes with a Spektrum Smart NiMH pack and an S120 USB-C charger. The Losi Mini-T 2.0 and Mini-B with battery and charger ($229.99 each) include a Smart G2 2S LiPo and a USB-C charger.
Side-by-side comparison
| Traxxas iD | Spektrum Smart G2 | |
|---|---|---|
| Main idea | Charger recognizes pack type, cell count and capacity | Pack has its own balancing, self-discharge and memory chip |
| Balance lead | Not detailed on the Traxxas pages reviewed | None; balances through a data wire |
| Auto storage | Charger offers storage mode (one-button on EZ-Peak Live 4S) | Pack self-discharges to 3.90 V/cell after 72 h by default |
| Charger requirement | iD charger for automatic setup | Spektrum Smart charger with G2 firmware required |
| Charger flexibility | EZ-Peak chargers also charge 5–8 cell NiMH | Smart chargers charge "nearly any RC hobby battery" |
| Entry charger price | Not captured for 2970 | $15.99 (S10 G2 USB-C) |
| Mid charger price | $119.95 (2971, 100 W) | $124.99 (S1100 G2, 100 W) |
| Dual charger price | $199.95 (2973, 200 W total) | $199.99 (S2100 G2, 2 × 100 W) |
Lock-in: pros and cons
The upside
- Fewer charging mistakes. Both systems set up the charge automatically.
- Convenience. Spektrum's auto-storage protects packs you forget about. Traxxas's app lets you monitor up to four EZ-Peak Live chargers.
- Simple bundles. Buying a truck, packs and charger from one brand means they are designed to work together.
The downside
- Charger dependence (Spektrum G2). G2 packs require a Smart charger with G2 firmware. If you already own a high-end third-party charger, it cannot charge G2 packs according to Spektrum.
- Connector juggling. Traxxas and Spektrum use different connectors, so moving packs between brands means adapters or connector changes.
- Harder to comparison-shop. Your choice of third-party packs may be narrower if you want the smart features.
Which should you choose?
In most cases, your car decides. If you have a Traxxas, iD packs and an EZ-Peak charger are the simplest path. If you have ARRMA or Losi, Spektrum Smart is the natural fit, and a Smart charger has the bonus of charging other batteries too. If you run a mix of brands, a Spektrum Smart charger is the more flexible hub based on Horizon's compatibility statement, but check Traxxas's manual before relying on it for iD packs. The sources we reviewed did not confirm how iD packs behave on non-Traxxas chargers.
What to watch out for
- Buying a non-G2 or third-party charger for G2 Smart packs.
- Assuming "smart" means you can skip safety basics: balance charging, a safe spot, LVD on.
- Trusting retailer amp ratings for connectors as if they were maker specs.
- Mixing up storage targets. Spektrum's pack default is 3.90 V per cell. Other makers suggest different figures.
FAQ
Can I charge a Spektrum Smart G2 battery on a regular hobby charger?
No. Horizon's FAQ says G2 Smart packs require a Spektrum Smart charger with G2 firmware, and Spektrum's product page says they are not compatible with non-Smart chargers.
Can a Spektrum Smart charger charge Traxxas batteries?
Horizon says Smart chargers can charge "nearly any RC hobby battery." You would still need the correct connector or adapter and settings. Check Traxxas's guidance before charging iD packs on a non-Traxxas charger.
Do Smart G2 batteries really store themselves?
Yes. By default they discharge to 3.90 V per cell after 72 hours unused, and the time and voltage are adjustable.
What does a Traxxas iD charger do automatically?
According to Traxxas, it recognizes the pack's type, cell count and capacity and enters the optimum settings.
Is the smart system worth paying extra for?
For beginners, automatic setup and (on Spektrum G2) auto-storage prevent common mistakes. Enthusiasts with existing chargers should weigh the G2 charger requirement.
Sources
- Traxxas: iD charger guide
- Traxxas: 2971 EZ-Peak Live 4S 12 amp charger
- Traxxas: 2973 EZ-Peak Live Dual charger
- Traxxas: 2997 Dual 4S LiPo Completer
- Traxxas: Battery Basics
- Traxxas: LiPo Batteries
- Traxxas: Slash 2WD XL-5 with battery
- Traxxas: Mini Maxx BL-2s
- Horizon Hobby: Smart G2 Battery and Charger FAQ (PDF)
- Horizon Hobby: Spektrum chargers
- Spektrum: S2200 G2 charger
- Spektrum: 11.1V 5000mAh 3S 30C Smart G2 LiPo (SPMX53S30)
- Spektrum: Adapter IC5 battery to IC3 device
- Horizon Hobby: TRI LiPo Battery Safety Sheet (PDF)
- Horizon Hobby: Our History
- EuroRC: RC connectors explained
- Horizon Hobby: ARRMA Gorgon with battery and charger
- Horizon Hobby: Losi Mini-T 2.0 with battery and charger
- Horizon Hobby: Losi Mini-B with battery and charger
