Battery Calculators
Battery Calculators
LEARNING CENTER

Engineering Guides

Practical explanations of core electrical engineering concepts. Each guide links to the relevant calculator so you can apply the formulas directly.

Cell Fundamentals

What Is Battery C-Rate?

Understand how C-rate governs charge and discharge current limits, and why it matters for cell longevity.

C-Rate Calculator
System Design

How to Calculate Battery Runtime

Step-by-step method for estimating discharge duration from capacity, load, and efficiency.

Runtime CalculatorBattery Sizing Calculator
System Design

How to Size a Battery Bank

Determine pack capacity from daily energy consumption, autonomy requirements, and temperature derating.

Battery Sizing CalculatorParallel String Calculator
Electrical

Voltage Drop Explained

Why cable resistance causes voltage loss, how to calculate it, and how to select the right wire gauge.

DC Voltage Drop CalculatorDC Cable Loss Calculator
Cell Fundamentals

Understanding State of Charge (SOC)

What SOC means, how it is measured, and why maintaining the right charge level extends battery life.

SOC EstimatorC-Rate Calculator
Cell Fundamentals

Battery Degradation Explained

How capacity fade and impedance rise reduce battery performance over time, and what you can do about it.

Degradation EstimatorSOC Estimator
Solar

How to Size a Solar Battery Bank

Size your solar battery bank from daily energy consumption, autonomy days, and depth of discharge.

Solar Battery Sizing CalculatorRuntime Calculator
Home Backup

Home Battery Backup Planning Guide

Plan home backup power by identifying critical loads, choosing duration, and sizing your battery bank.

Home Backup CalculatorCharging Time Calculator
RV & Camper

RV Battery Sizing Guide

Size your RV battery bank for boondocking by cataloging loads, choosing voltage, and selecting chemistry.

RV Battery CalculatorInverter Battery Calculator
Marine

Marine Battery Sizing Guide

Size marine house banks for hotel loads, account for the marine environment, and choose the right chemistry.

Marine Battery Sizing CalculatorRuntime Calculator
EV & Battery Packs

Battery Pack Design Basics

Understand series and parallel cell configurations, pack sizing, and key design considerations.

Battery Pack CalculatorParallel String Calculator
BESS & Commercial

BESS ROI Explained

Evaluate commercial battery storage investments with NPV, payback period, and IRR analysis.

BESS ROI CalculatorEnergy Conversion Calculator
System Design

How Long Will a Battery Last?

Calculate battery runtime from capacity, load, efficiency, and depth of discharge with worked examples.

Runtime CalculatorBattery Sizing Calculator
Charging

How Long to Charge a Battery

Estimate charging time using C-rate, charger current, and the CC-CV charging profile.

Charging Time CalculatorC-Rate Calculator
Practical Examples

How Long Will a 200Ah Battery Last?

Runtime examples for 200Ah batteries powering RV, marine, solar, and home backup loads.

Runtime CalculatorSolar Battery Sizing Calculator
Solar

How Long Will My Solar Battery Last?

Estimate solar battery runtime at night and during cloudy periods for off-grid and hybrid systems.

Solar Battery Sizing CalculatorRuntime Calculator
System Design

How to Calculate Runtime of a Battery

Complete engineering method for calculating battery runtime with accuracy.

Runtime CalculatorBattery Sizing Calculator
Practical Examples

How Long Will a 100Ah Battery Last?

Detailed runtime examples for 100Ah batteries at 12V, 24V, and 48V across common loads.

Runtime CalculatorBattery Sizing Calculator
Practical Examples

How Long Will a 300Ah Battery Last?

Runtime examples for 300Ah batteries in home backup, RV, and off-grid solar applications.

Runtime CalculatorSolar Battery Sizing Calculator
Chemistry

LiFePO4 Battery Runtime Guide

Deep dive into LiFePO4 runtime characteristics, discharge curves, and temperature effects.

Runtime CalculatorSolar Battery Sizing Calculator
Chemistry

Lithium Battery Runtime Guide

Lithium battery runtime characteristics across LFP, NMC, and NCA chemistries.

Runtime CalculatorDegradation Estimator
Applications

UPS Battery Runtime Guide

How to estimate and extend UPS battery runtime for computers, servers, and critical equipment.

Runtime CalculatorHome Backup Calculator
Electrical

Inverter Battery Runtime Guide

How inverter efficiency affects battery runtime with practical calculations for AC loads.

Runtime CalculatorInverter Battery Calculator
Reference

Battery Runtime Formula

Complete formula reference for all battery runtime calculations including temperature and efficiency.

Runtime CalculatorInverter Battery Calculator
Electrical

12V vs 24V vs 48V Runtime

How system voltage affects runtime, efficiency, and cable sizing for battery systems.

Runtime CalculatorVoltage Drop Calculator
System Design

What Is Battery Sizing?

Introduction to battery sizing: what it means, why it matters, and the engineering process.

Battery Sizing CalculatorSolar Battery Sizing Calculator
Reference

Battery Sizing Formula

Complete formula reference for battery sizing across all applications and chemistries.

Battery Sizing CalculatorRuntime Calculator
Reference

Battery Sizing Chart Guide

Visual reference charts showing battery sizes for common load profiles and applications.

Battery Sizing CalculatorHome Backup Calculator
Applications

UPS Battery Sizing Guide

How to size UPS batteries for computers, servers, medical equipment, and critical loads.

Runtime CalculatorBattery Sizing Calculator
Home Backup

Home Battery Sizing Guide

How to size a battery for home backup: critical loads, duration, and voltage selection.

Home Backup CalculatorBattery Sizing Calculator
Solar

How Many Batteries for Solar?

How to determine the number of batteries needed for a solar energy storage system.

Solar Battery Sizing CalculatorRuntime Calculator
Solar

How Much Battery Storage Do I Need?

Calculate total battery storage from daily consumption and autonomy requirements.

Solar Battery Sizing CalculatorBattery Sizing Calculator
Solar

Solar Battery Backup Guide

How solar batteries provide backup during grid outages in hybrid and off-grid systems.

Solar Battery Sizing CalculatorHome Backup Calculator
Solar

Off-Grid Battery Planning

Complete guide to planning battery systems for off-grid solar installations.

Solar Battery Sizing CalculatorRuntime Calculator
Solar

Solar Storage Sizing Guide

End-to-end guide to sizing solar storage from consumption analysis to battery selection.

Solar Battery Sizing CalculatorBattery Sizing Calculator
Home Backup

How Many kWh Do I Need for My House?

Calculate household kWh needs for battery backup with consumption tables by home size.

Home Backup CalculatorBattery Sizing Calculator
Home Backup

Power Outage Battery Guide

How to prepare a battery system for power outages with critical load planning.

Home Backup CalculatorRuntime Calculator
Home Backup

Whole House Battery Backup

Sizing a battery system to back up an entire house during extended outages.

Home Backup CalculatorBattery Sizing Calculator
Home Backup

Generator vs Battery Backup

Comparison of generators and batteries for backup power: costs, runtime, and hybrid approaches.

Home Backup CalculatorBattery Sizing Calculator
Home Backup

Home Backup Runtime Guide

How long different battery sizes last for home backup at various load levels.

Home Backup CalculatorRuntime Calculator
RV & Camper

Camper Battery Runtime Guide

Battery runtime for camper vans with common load tables and weekend trip examples.

RV Battery CalculatorRuntime Calculator
RV & Camper

Van Life Battery Planning

Complete battery planning guide for van life: loads, consumption, solar, and sizing.

RV Battery CalculatorSolar Battery Sizing Calculator
RV & Camper

How Many Batteries for RV?

How to determine the number of batteries for weekend camping vs full-time RV living.

RV Battery CalculatorBattery Sizing Calculator
RV & Camper

RV Lithium Battery Guide

Why lithium LFP is the best battery chemistry for RV applications with cost analysis.

RV Battery CalculatorRuntime Calculator
Marine

Boat Battery Runtime Guide

Battery runtime for boats: trolling motors, fish finders, navigation, and marine loads.

Marine Battery Sizing CalculatorRuntime Calculator
Marine

Yacht Battery Planning

Complete battery planning for yachts: hotel loads, anchoring vs cruising, and sizing.

Marine Battery Sizing CalculatorRuntime Calculator
Marine

Marine Hotel Load Guide

How to inventory and calculate marine hotel loads for battery system sizing.

Marine Battery Sizing CalculatorBattery Sizing Calculator
Marine

Lithium Marine Batteries

Why lithium LFP is replacing lead-acid in marine applications with comparison data.

Marine Battery Sizing CalculatorRuntime Calculator
Charging

How Long to Charge a Lithium Battery

Charging times for LFP and NMC lithium batteries at different C-rates and charger sizes.

Charging Time CalculatorC-Rate Calculator
Charging

How Long to Charge a 100Ah Battery

Specific charging times for 100Ah batteries at 0.1C, 0.2C, 0.5C, and 1C rates.

Charging Time CalculatorRuntime Calculator
Reference

Battery Charging Formula

Complete formula reference for battery charging calculations: CC phase, CV phase, and total time.

Charging Time CalculatorC-Rate Calculator
Charging

Charger Sizing Guide

How to select the right charger size for your battery based on chemistry and desired charge time.

Charging Time CalculatorC-Rate Calculator
Electrical

Series vs Parallel Batteries

Series vs parallel connections: how each affects voltage, capacity, and pack configuration.

Battery Pack CalculatorParallel String Calculator
Electrical

Battery Voltage Systems

Common battery voltage systems: 12V, 24V, 36V, 48V and how they are built from cells.

Battery Pack CalculatorParallel String Calculator
Electrical

How to Build a Battery Pack

Step-by-step guide to building a battery pack from individual cells with BMS and safety.

Battery Pack CalculatorParallel String Calculator
Electrical

LiFePO4 Pack Design

LFP-specific pack design: cell matching, balancing, thermal management, and configurations.

Battery Pack CalculatorParallel String Calculator
Reference

LiFePO4 Voltage Chart

Approximate resting voltage table for LiFePO4 batteries at 12V, 24V, and 48V by SOC level.

SOC EstimatorRuntime Calculator
Reference

LiFePO4 SOC Chart

Why LiFePO4 voltage is flat in the middle SOC range, and why coulomb counting is often better.

SOC EstimatorRuntime Calculator
Reference

Lead-Acid Voltage Chart

Voltage reference tables for flooded, AGM, and gel lead-acid batteries by state of charge.

Battery Sizing CalculatorRuntime Calculator
Reference

Battery Depth of Discharge Chart

DoD limits by chemistry with usable capacity calculations and cycle life implications.

Battery Sizing CalculatorDegradation Estimator
Reference

Battery Temperature Correction Chart

How temperature affects capacity, charging safety, and degradation risk across lithium and lead-acid.

Degradation EstimatorCharging Time Calculator
Reference

Battery C-Rate Reference

C-rate to current conversion table for 50Ah, 100Ah, 200Ah, and 300Ah batteries.

C-Rate CalculatorCharging Time Calculator
Reference

Battery Sizing Reference

Practical sizing tables for RV, solar, marine, home backup, and commercial BESS applications.

Battery Sizing CalculatorSolar Battery Sizing Calculator
Practical Examples

How Long Will a 50Ah Battery Last?

Runtime examples for 50Ah batteries powering small electronics, emergency kits, and minimal loads.

Runtime CalculatorBattery Sizing Calculator
Practical Examples

How Long Will a 400Ah Battery Last?

Runtime examples for 400Ah batteries in full-time RV, home backup, and extended off-grid applications.

Runtime CalculatorSolar Battery Sizing Calculator
Electrical

12V vs 24V vs 48V Batteries

Complete comparison of 12V, 24V, and 48V battery systems with trade-offs for capacity, efficiency, and wiring.

Runtime CalculatorBattery Sizing Calculator
Solar

24V vs 48V Solar Systems

Compare 24V and 48V solar battery systems for cost, efficiency, and scalability.

Solar Battery Sizing CalculatorDC Voltage Drop Calculator
RV & Camper

12V vs 24V RV Batteries

Compare 12V and 24V battery systems for RV and camper applications.

RV Battery CalculatorRuntime Calculator
Marine

Marine Battery Voltage Selection

How to choose between 12V, 24V, and 36V for marine house banks and engine starting.

Marine Battery Sizing CalculatorRuntime Calculator
Chemistry

LiFePO4 vs Lead-Acid

Head-to-head comparison of LiFePO4 and flooded lead-acid batteries across all key metrics.

Battery Sizing CalculatorDegradation Estimator
Chemistry

LiFePO4 vs AGM

Compare LiFePO4 and AGM sealed lead-acid batteries for deep-cycle applications.

Battery Sizing CalculatorDegradation Estimator
Chemistry

LiFePO4 vs Gel

Compare LiFePO4 and gel cell batteries for solar, marine, and backup applications.

Battery Sizing CalculatorDegradation Estimator
Chemistry

LiFePO4 vs NMC

Compare LiFePO4 and NMC lithium-ion chemistries for safety, energy density, and cycle life.

Battery Pack CalculatorDegradation Estimator
Chemistry

Best Battery Chemistry for Solar

Ranking of battery chemistries for solar storage with cost, cycle life, and safety analysis.

Solar Battery Sizing CalculatorBattery Sizing Calculator
Chemistry

Best Battery Chemistry for RV

Ranking of battery chemistries for RV applications with weight, DoD, and vibration analysis.

RV Battery CalculatorRuntime Calculator
Chemistry

Best Battery Chemistry for Marine

Ranking of battery chemistries for marine house banks and engine starting.

Marine Battery Sizing CalculatorRuntime Calculator
Reference

LiFePO4 Charge Voltage Table

Complete charge voltage reference for LiFePO4 cells and packs at 12V, 24V, and 48V.

Charging Time CalculatorSOC Estimator
Reference

Battery Efficiency Reference

Round-trip efficiency by chemistry, inverter efficiency ratings, and total system loss calculations.

Runtime CalculatorInverter Battery Calculator
Reference

Common Battery Sizes Reference

Standard battery capacities from 7Ah to 400Ah with energy ratings and typical applications.

Battery Sizing CalculatorEnergy Conversion Calculator
Reference

Battery Energy Density Chart

Compare gravimetric and volumetric energy density across LiFePO4, NMC, and lead-acid chemistries.

Battery Pack CalculatorBattery Sizing Calculator