Tech-dat/power-dat/battery-dat/battery-dat.md
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- [[battery-rechargerable-dat]] - [[lithium-battery-dat]] - [[lead-acid-battery-dat]] - [[LFP-dat]]
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-- [[battery-holder-dat]]
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+- [[battery-pack-dat]] - [[battery-holder-dat]]
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- [[battery-charger-dat]] - [[2S-lithium-battery-charger-dat]]
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- [[alkaline-battery-dat]] - [[9V-battery-dat]]
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-- [[battery-soldering-dat]]
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+- [[battery-soldering-dat]] - [[battery-tester-dat]]
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+
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+- [[battery-discharge-dat]]
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-- battery isolation == rack (specially when have movement or vibration), Insulating Gasket
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Tech-dat/power-dat/battery-dat/battery-discharge-dat/battery-discharge-dat.md
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+# battery-discharge-dat
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+
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+
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+## C-Rate
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+
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+**C-rate** is a measure of how fast a battery is charged or discharged relative to its capacity.
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+
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+### 🔹 Formula:
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+
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+ C-rate × Capacity (Ah) = Current (A)
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+
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+### 🧮 Examples:
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+- For a **500mAh (0.5Ah)** battery:
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+ - **1C** = 0.5A
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+ - **2C** = 1A
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+ - **30C** = 15A
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+
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+- For a **1000mAh (1Ah)** battery:
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+ - **1C** = 1A
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+ - **10C** = 10A
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+
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+### 📌 In Simple Terms:
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+- **1C** = full charge/discharge in **1 hour**
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+- **2C** = in **30 minutes**
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+- **10C** = in **6 minutes**
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+- **30C** = in **2 minutes**
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+
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+> Higher C-rates mean **more current**, which leads to **more heat**, **more stress**, and requires better battery and driver design.
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+
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+
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+
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+## info
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+
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+- [[L293-dat]]
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+
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+## ⚠️ Can I Use L293 to Discharge and Drive DC Motors at 30C?
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+
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+### ❌ Short Answer:
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+**No**, the L293 (or L293D) is not suitable for handling high discharge currents like **30C**, especially from lithium batteries. It is far too limited in current handling.
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+
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+---
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+
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+### 🔧 Quick Comparison Table
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+
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+| Feature | L293D / L293 (typical) | Requirement for 30C Discharge |
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+| --------------------------------- | ----------------------------- | ----------------------------------------------- |
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+| **Max Continuous Output Current** | ~600 mA (L293D) to 1A (L293) | Often 15A+ (for 500mAh @ 30C) |
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+| **Peak Current** | Up to 1.2A (very short burst) | Much higher (30C = 15A!) |
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+| **Output Voltage Drop** | High (2–3V loss) | Not acceptable for high power |
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+| **Thermal Handling** | Poor (gets hot quickly) | Needs heatsinking, high current design |
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+| **PWM Support** | Yes (limited frequency) | OK, but irrelevant if current limit is breached |
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+
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+---
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+
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+### 🔋 What Happens at 30C Discharge?
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+
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+Example: 14500 Li-ion (500mAh) @ 30C
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+→ 0.5Ah × 30C = **15A**
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+
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+- L293 can only handle **0.6A–1A max**, **not even close**
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+- Same applies for 18650 (e.g., 3000mAh × 30C = 90A)
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+
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+---
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+
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+### 🔥 Risks of Using L293 at High C-Rates
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+
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+- **Overheating** and possible **component failure**
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+- **Battery damage** from over-discharge
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+- **Motor underperformance**
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+- **Voltage drops** and high inefficiency
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+- Possible **fire hazard** with lithium cells
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+
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+---
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+
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+### ✅ Better Alternatives
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+
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+Use high-current drivers designed for motors and Li-ion/LiPo cells:
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+
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+| Driver/Controller Type | Suitable Current Range | Notes |
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+| ------------------------------------- | ---------------------- | -------------------------------------- |
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+| **MOSFET H-Bridge** | 10A – 100A+ | Efficient, low heat loss |
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+| **VNH5019 / BTS7960** | 12A – 40A | Great for higher-power motors |
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+| **ESC (Electronic Speed Controller)** | 10A – 100A+ | Designed for brushless and RC motors |
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+| **L298N** | Up to ~2A | Still too weak for high-C applications |
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+
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+---
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+
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+### ✅ Rule of Thumb
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+
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+If your motor requires **more than 1A**, **avoid L293/L293D**.
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+Use a **MOSFET-based** driver or **high-current motor controller** instead. - [[mosfet-dat]]
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+
Tech-dat/power-dat/battery-dat/battery-rechargerable-dat/lithium-battery-dat/li-battery-size-dat/18650-dat/18650-dat.md
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- [[18650-battery-holder-dat]]
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----
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+## 14500 vs 18650 vs 21700 batteries
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+
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+| Feature | AA Size Lithium (14500) | 18650 Lithium-Ion | 21700 Lithium-Ion |
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+| ---------------------------- | -------------------------- | --------------------------- | ------------------------- |
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+| **Typical Size (mm)** | 14 x 50 | 18 x 65 | 21 x 70 |
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+| **Nominal Voltage** | 3.7V | 3.6V – 3.7V | 3.6V – 3.7V |
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+| **Capacity Range** | 500 – 800 mAh | 1800 – 3500 mAh | 4000 – 5000+ mAh |
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+| **Max Continuous Discharge** | 1 – 3A | 5 – 20A | 10 – 35A |
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+| **Common C-Rate** | 1C – 3C | 1C – 10C | 1C – 10C+ |
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+| **Rechargeable** | Yes | Yes | Yes |
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+| **Common Use Cases** | Small flashlights, sensors | Laptops, power tools, vapes | EVs, e-bikes, power tools |
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+| **Weight (approx.)** | ~20g | ~45g | ~70g |
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+| **Energy Density** | Low – Medium | Medium | High |
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+
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+
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+
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## **18650 Battery Types**
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-| **Type** | **Main Composition** | **Features** | **Applications** |
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-|---------|-----------------|-----------------|-----------------|
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-| **NCM/NCA** | Nickel-Cobalt-Manganese / Nickel-Cobalt-Aluminum | High energy density, medium safety | EVs (Tesla Model S/X), laptop batteries |
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-| **LFP (Lithium Iron Phosphate)** | Lithium Iron Phosphate | Long lifespan, high safety, lower energy density | Energy storage, power tools, e-bikes |
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-| **LCO (Lithium Cobalt Oxide)** | Lithium Cobalt Oxide | High energy density, shorter lifespan | Laptops, battery packs |
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-| **IMR (Lithium Manganese Oxide)** | Lithium Manganese Oxide | High discharge rate, heat resistance | High-power flashlights, vaping devices |
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+
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+| **Type** | **Main Composition** | **Features** | **Applications** |
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+| --------------------------------- | ------------------------------------------------ | ------------------------------------------------ | --------------------------------------- |
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+| **NCM/NCA** | Nickel-Cobalt-Manganese / Nickel-Cobalt-Aluminum | High energy density, medium safety | EVs (Tesla Model S/X), laptop batteries |
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+| **LFP (Lithium Iron Phosphate)** | Lithium Iron Phosphate | Long lifespan, high safety, lower energy density | Energy storage, power tools, e-bikes |
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+| **LCO (Lithium Cobalt Oxide)** | Lithium Cobalt Oxide | High energy density, shorter lifespan | Laptops, battery packs |
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+| **IMR (Lithium Manganese Oxide)** | Lithium Manganese Oxide | High discharge rate, heat resistance | High-power flashlights, vaping devices |
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---
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## **18650 vs. 21700 Batteries**
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-| **Model** | **Size** | **Energy Density** | **Common Uses** |
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-|----------|--------|----------------|---------------|
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-| **18650** | 18 × 65 mm | 2000 – 3500mAh | Laptops, EVs, tools |
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-| **21700** | 21 × 70 mm | 4000 – 5000mAh | Tesla batteries, energy storage |
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+| **Model** | **Size** | **Energy Density** | **Common Uses** |
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+| --------- | ---------- | ------------------ | ------------------------------- |
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+| **18650** | 18 × 65 mm | 2000 – 3500mAh | Laptops, EVs, tools |
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+| **21700** | 21 × 70 mm | 4000 – 5000mAh | Tesla batteries, energy storage |
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Tesla originally used **18650 batteries** in **Model S/X** but later switched to **21700** for **Model 3/Y** and is now moving towards **4680** cells for higher efficiency.
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----
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The 18650 battery should fall under the Lithium-ion Battery category, as it is a specific form factor of the lithium-ion battery, commonly used in applications such as laptops, power tools, flashlights, and electric vehicles.
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Tech-dat/power-dat/battery-pack-dat/battery-pack-dat.md
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- battery test by [[electronic-loader-dat]]
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+- check [[battery-discharge-dat]]
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+
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+- battery isolation == rack (specially when have movement or vibration), Insulating Gasket
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## Simple 1S to 2S management Solutions
app-dat/RC-dat/rover-dat/rc-car-dat/rc-car-hack-dat/rc-car-hack-dat.md
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- [[lithium-battery-dat]] - [[battery-pack-dat]]
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+
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## 2. RC Signal Extension
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- improve up to 10KM by [[FPV-dat]] system [[ELRS-dat]], or [[PPM-dat]] == [[Wfly-dat]]
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- [[video-transmission-dat]] == pickup option == [[LTE-dat]]
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## 4. GNSS location system
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- [[location-dat]]