FAQ

Answers to common questions about batteries, bulbs, lighting, and ordering. Don't see yours? Contact us — we've been answering these since 1992.

Batteries — finding the right replacement

How do I find the right replacement battery?

Match three things: voltage (must be the same), the physical size or model number, and the terminal type. Capacity (mAh or Ah) can be equal or higher. If you're unsure, enter the number printed on your old battery or your device's make and model in our search, or send us the details and we'll match it.

Can I use a battery with a higher mAh or Ah rating?

Yes — as long as the voltage and physical size/terminals are the same, a higher mAh/Ah rating simply means longer runtime and won't harm your device. Never change the voltage.

What's the difference between alkaline, lithium, and NiMH batteries?

Alkaline are inexpensive single-use cells for everyday devices. Lithium and lithium-ion offer higher energy density, longer life, and better cold-weather performance. NiMH are rechargeable and well suited to high-drain devices. Tell us your device and we'll recommend the right chemistry.

Can I replace a sealed lead-acid (SLA) battery with LiFePO4?

Often yes. LiFePO4 (lithium iron phosphate) is a drop-in upgrade for many 12V SLA applications — far lighter, with a much longer cycle life. Match the voltage and terminal type, and confirm your charger supports lithium (many do, or have a lithium setting). See our LiFePO4 SLA replacements.

Do you carry hard-to-find or obsolete batteries?

Yes — odd sizes, specialty chemistries, and discontinued batteries are our specialty. See Hard-to-Find Batteries & Bulbs.

Bulbs & LED retrofit

Can I replace fluorescent tubes with LED?

Yes. Most T12, T8, and T5 fluorescent tubes have a direct LED replacement. You match the size, length, and base, then choose plug-and-play (keep ballast) or ballast-bypass (direct-wire). Full details in our Fluorescent to LED Guide.

How do I read a light bulb code?

A bulb code combines a shape letter and a size number — for example, A19 means an "A" shape that is 19 eighths of an inch (about 2 3/8") in diameter. The base is listed separately (e.g., E26 medium screw). See our Bulb Shapes and Sizes guide.

What color temperature should I choose?

2700–3000K is warm white (cozy, residential), 3500–4000K is neutral or cool white (kitchens, offices), and 5000K is daylight (garages, workshops, retail). All describe the light's color, measured in Kelvin.

Are incandescent and halogen bulbs still legal in California?

Most general-service incandescent and halogen bulbs have been phased out under federal efficiency standards and California Title 20, though many specialty types remain available. LED equivalents are the compliant, energy-saving replacement. See our Lighting Regulations & Safety page.

Commercial & bulk orders

Do you offer volume or contractor pricing?

Yes. We offer bulk and contract pricing for contractors, facilities, and businesses. See our Bulk & Commercial page or email sales@batteriesnbulbs.com.

Can I get a quote for a large or recurring order?

Yes. Send your list, BOM, or spec sheet to sales@batteriesnbulbs.com and we'll quote pricing and availability quickly.

Do you offer dedicated account support and terms?

Yes — qualified business buyers get a dedicated account contact, and account terms are available. Just ask when you request a quote.

Do you ship nationwide?

Yes. We offer free nationwide shipping on every order across the United States.

Incandescent & halogen lamps

What is an incandescent light source?

Incandescent light sources are electric bulbs with filaments. When electric energy is transformed into heat energy, the temperature of the solid body is raised. The heated body gives off different levels of light according to the degree to which it has been heated. Halogen bulbs fall under this category.

What materials are used in halogen lamps?

There are two kinds of bulbs used in halogen lamps: transparent and translucent quartz bulbs. Materials inside the halogen lamp include a tungsten filament, molybdenum foil, and filling gases consisting of a combination of nitrogen, argon, krypton and a small amount of halogen gas made up of iodine, bromine, chlorine, and fluorine. The base of the lamp is usually made of steatite or heat-resistant metal.

Why is the halogen bulb made of quartz?

Quartz is used in halogen bulbs because it can withstand high temperatures. Quartz also ensures against heat shock.

Why is tungsten used as the filament?

Tungsten is used because of its high flexibility and low rate of evaporation at high temperatures. Tungsten also has a very high melting point of 3400°C, which lends to its slow evaporation.

Why is molybdenum foil used inside the halogen lamp?

Molybdenum foil is used as a conductor through the seal part of the lamp. It ensures the hermetic sealing of the lamp. Molybdenum has almost the same thermal expansion properties as quartz.

How does a halogen lamp work?

It works through the halogen cycle. As tungsten evaporates from the filament, it combines with halogen gas and becomes tungsten halide. When the tungsten halide nears the filament, the heat of the filament separates the tungsten from the halogen gas, redepositing the tungsten on the filament. The freed halogen gas then repeats the same process — thus, the halogen cycle.

How do halogen lamps give constant light output?

The halogen cycle effectively prevents blackening of the bulb wall, so there is no reduction of light output or color temperature over the lamp's life.

How does a halogen bulb give a longer lamp life?

Halogen bulbs are more efficient than ordinary incandescent bulbs. They can give a longer lamp life expectancy because of the halogen cycle.

What is color temperature?

Color temperature describes the warm-to-cool color of light, measured in Kelvin. For the full explanation, see our Characteristics of Light guide.

Why does a light bulb burn out?

Due to the high temperature the tungsten filament operates at, some of the tungsten evaporates during use. This leaves the filament thinner in some areas. The weakened area becomes hotter, which leads to even faster evaporation, causing the filament to burn back and the lamp to burn out.

Why do some bulbs burn out the instant they are turned on?

The thinned filament in a cold state cannot withstand the inrush surge of energy, and so the bulb burns out at the moment of switch-on.

What are the common causes of lamp failure?

The most common causes are overheating and over-voltage.