Question 1

What is the capacity of my battery?

Accepted Answer

The unit used to describe battery capacity is an Ampere-hour (Ah). This is a measure of how long a continuous current can be supplied before completely draining the battery of useful energy. There should be an indication on the battery that gives an Ah value. The most common discharge rates are 20h, 8h and 1h. Example: a 20Ah battery can supply 1A for 20h.

Question 2

What is energy density?

Accepted Answer

It is the amount of energy that can be stored in a volume or mass. Volumetric energy density is energy per litre (Wh/l). Gravimetric energy density is energy per kilogram (Wh/kg).

Question 3

How long does it take to charge a battery?

Accepted Answer

If the charging current (I) and the capacity of the battery (C) in Ah are known, charging time ≈ (C / I) × 1.2. The 1.2 factor adds 20% extra time to ensure the charge cycle is fully complete.

Question 4

Will any charger work with any battery?

Accepted Answer

No. Each battery chemistry and each capacity requires a different charger because the detection methods and maximum charge rates vary by chemistry. A charger designed for a 10Ah lead-acid battery will not be suitable for a 10Ah battery in any other chemistry. Carefully check both chemistry and capacity when selecting a charger.

Question 5

How can I find the manufacturing date of my product?

Accepted Answer

On each product there is a label that indicates the year and week of manufacture.

Question 6

How do I select an appropriate power supply?

Accepted Answer

A power supply delivers a fixed voltage up to a maximum current, and only delivers the current required by the device. A device requiring 0.8A will function perfectly using a 1A power supply provided the output voltage is correct. If you're unsure, email tech@pulsardevelopments.com or call 01189 795319, Mon–Fri 08:00–17:30.

Question 7

Should I fully discharge my battery before charging it?

Accepted Answer

This depends on chemistry. A lead-acid battery should ideally not be drained further than 50% to prevent sulphation. Li-Ion, NiMH and LiFePO4 can be used to very low percentages and recharged with no issue. NiCd batteries are prone to memory effect and should occasionally be fully drained to 'reset' their capacity memory.

Question 8

How should I store my battery?

Accepted Answer

Lead-acid: store as fully charged as possible at ~20°C; lasts 6 months–2 years depending on quality. NiCd / NiMH / Li-Ion / LiFePO4: store cool and dry at approx. 40% charge - NiCd 1.5–3 years, NiMH ~3–5 years, Li-Ion and LiFePO4 2–5 years. Ideal storage can double these. Consult manufacturer guidelines for specifics.

Question 9

Can Pulsar fit output cable connectors?

Accepted Answer

Yes. Our engineers fit a wide range of output connectors. Provide a connector type/spec (preferably with a product code) and polarity, and we'll fit and 100% test it. Email tech@pulsardevelopments.com or call 01189 795319.

Question 10

Can Pulsar provide batteries for my charger?

Accepted Answer

Yes - we source and supply lead-acid, NiMH and Li-Ion batteries and cell packs, including custom-made battery packs. Contact us directly to discuss your requirement.

Question 11

Can Pulsar provide a power supply or charger to meet exact requirements?

Accepted Answer

Yes. With support from Mascot's experienced design team we can either configure standard products or generate a custom design where no standard solution exists. Contact tech@pulsardevelopments.com.

Question 12

Can Pulsar programme NiMH charger parameters?

Accepted Answer

Yes. Adjustable parameters include negative voltage drop (-dV), temperature gradient (dT/dt), safety timer, start timer and top-off charge timer.

Question 13

Does temperature affect battery performance?

Accepted Answer

Yes. Cold slows the internal reactions, reducing electrical performance. Heat increases self-discharge, lowering effective capacity. Each manufacturer publishes an operating temperature range for optimal performance.

Question 14

Are there potential dangers when carrying loose batteries?

Accepted Answer

Yes. Terminals can be short-circuited by metal in pockets (e.g. coins), damaging the battery and surroundings. Always fit terminal covers when transporting batteries.

Question 15

Can NiCd batteries be replaced with NiMH batteries?

Accepted Answer

Not without also changing the charger. NiMH chargers are more sensitive at detecting end-of-charge - a NiCd charger cannot be used on NiMH, although a NiMH charger can charge NiCd batteries.

Question 16

Can NiCd / NiMH / Lead-Acid batteries be replaced by Li-Ion batteries?

Accepted Answer

No. Li-Ion batteries are much more energy dense and work at different voltages. Systems and chargers are designed specifically for Li-Ion - using them outside those design considerations can damage devices and pose safety risks.

Question 17

Can battery brands, ages and chemistries be mixed?

Accepted Answer

No. Each chemistry and capacity requires a unique charging solution; different ages will have varying capacities and give false charging signals. Batteries in a device should always be the same chemistry, voltage, capacity and age.

Question 18

What does IP rating represent?

Accepted Answer

IP (Ingress Protection) classifies and rates protection against intrusion, dust, accidental contact and water. The first digit is intrusion protection; the second is moisture protection. Higher numbers indicate greater protection. See our Technical Resources for the full chart.

Question 19

What is an 'alternative' item?

Accepted Answer

An exact alternative is functionally identical (minor differences such as size are highlighted). An upgrade alternative is a newer design or has additional approvals (e.g. medical) from the same manufacturer. A suggested alternative is functionally similar - all differences highlighted so you can confirm fit for your application.

Question 20

At what rate do I charge my battery? (Lead-Acid, SLA)

Accepted Answer

Identify the battery voltage and match the charger voltage. Divide capacity (Ah) by 4 to get the maximum charging current. Example: a 24V 20Ah lead-acid battery needs a 24V 5A charger. A lower charge current also works (slower but safe). Three-step charging - constant-current boost, constant-voltage absorption, then float - gives the shortest charge time while preserving battery health.

Question 21

At what rate do I charge my battery? (Lithium-Ion)

Accepted Answer

Each cell is 4.2V; a 10-cell Li-Ion pack is 42V, a 2-cell is 8.4V. Choose a charger matching the pack voltage. Charge current = C/2 is a good estimate to prolong life. Example: a 4-cell 7Ah Li-Ion pack → 16.8V at 3.5A charger.

Question 22

At what rate do I charge my battery? (LiFePO4)

Accepted Answer

Each LiFePO4 cell needs 3.65V - 4-cell = 14.6V, 7-cell = 25.55V. A current of 0.5C–0.8C prolongs life. Example: a 4-cell 7Ah LiFePO4 battery → 14.6V at 3.5A (0.5C).

Question 23

At what rate do I charge my battery? (NiMH / NiCd)

Accepted Answer

NiMH/NiCd are the most complex to charge - end-of-charge detection uses voltage drop (-dV) or temperature rise (dT/dt) and requires a smart charger. Each cell needs ~1.4–1.6V; charging current 0.5–1C ensures a detectable signal. After detection, a top-off current of ~C/10 runs for ~1 hour. An override safety timer (OST) prevents damage from overcharging - Pulsar can set custom OSTs.

Technical Frequently Asked Questions