Bright Way 6V 4.5Ah Rechargeable Spade-Top Battery

A sealed 6-volt battery with F1 spade terminals for compatible equipment that calls for a 4.5Ah BW 645 replacement.

Match the battery before you buy

This is a specific replacement size, not a general-purpose battery for every fence charger or barn device. The BW 645 is rated at 6 volts and 4.5 amp-hours, with F1 spade terminals. Check the old battery or the equipment manual before ordering. Voltage must match the device. The terminal shape and spacing must suit its leads, and the case needs to fit the battery compartment without pressure on the cover. A familiar-looking battery can still be the wrong replacement if one of those details differs.

A compact sealed lead-acid design

This sealed AGM battery uses an absorbent glass mat separator and is non-spillable. Its sealed construction does not remove charging precautions: do not charge it in a sealed container, and keep the charging area ventilated. The case has positive and negative F1 spade terminals at the top. Check polarity before connecting leads and keep conductive tools away from the terminals. A short circuit can damage the battery and create a fire or burn hazard.

Understand the amp-hour rating

The 4.5Ah rating is measured at a 20-hour discharge rate. Capacity changes with the load and discharge period, so that number is a comparison point, not a promise that every device will run for the same length of time. A higher-draw unit can use the available capacity faster. For equipment that runs intermittently, the actual interval between charges depends on how often it operates and the current it draws. Keep the device’s required voltage and capacity range in view when comparing replacements.

Check the footprint and charging setup

The BW 645 case measures about 2.76 inches long, 1.85 inches wide and 3.98 inches high, before allowing for the terminals. The full height to the terminals is about 4.21 inches. Measure the battery compartment, including clearance above the case, before removing the old unit. This avoids forcing the leads or cover into place. Use a charger intended for a 6-volt sealed lead-acid battery and follow the equipment or charger instructions. Do not choose charging settings by the plug shape alone.

When a replacement makes sense

If the battery will sit unused, store it fully charged in a cool, dry place and check it periodically. At 25°C, remaining capacity is about 91% after three months, 82% after six months and 65% after twelve months. That gradual self-discharge matters for backup equipment kept on a shelf. Recharge it before service with a compatible 6-volt charger, using the charging mode specified for the equipment. Do not let voltage fall below the printed 5.25-volt damage threshold.

Battery specifications

Nominal voltage: 6 V. Capacity at 20-hour rate: 4.5 Ah; at 10-hour rate: 4.2 Ah; at 1-hour rate: 2.95 Ah. Terminal type: F1 spade. Construction: sealed lead-acid AGM. Case dimensions: 2.76 × 1.85 × 3.98 in. Total height to terminals: 4.21 in. Approximate battery mass: 1.50 lb ±5%.

At 25°C, float 6.80–6.90 V; cyclic 7.25–7.50 V; maximum charging current 1.35 A. Use charger and equipment instructions to determine applicable settings.

Directions for use

Use only with equipment specified for a 6 V battery with compatible F1 terminals. Connect positive to positive and negative to negative. Use a charger intended for 6 V sealed lead-acid batteries and follow the equipment charging instructions. Charge in a ventilated area, not in a sealed container.

Cautions

WARNING: Risk of fire, explosion or burns. Do not disassemble or heat above 65°C (149°F). Do not short-circuit the terminals. Avoid total discharge; damage occurs below 5.25 V. Do not charge in a sealed container. This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.