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Alaris Micro 1 Spirometer 2.4V Replacement Battery 36-BAT1043

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From $43.99 USD $54.99
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Fits Alaris Micro 1 Spirometer; replaces OEM part numbers 36-BAT1043 and OM11861.
2.4V, 2000mAh Ni-MH chemistry delivers consistent power for pulmonary function testing cycles without voltage sag.
Connector slides into the battery slot at the device base with positive terminal forward; locking tab seats flush against the housing.
We bench-tested this cell through full charge-discharge cycles; the BMS accepted the new pack after the second charge without fault codes.
After installation, allow the spirometer to complete its power-on self-test without interruption — the device runs BMS verification at startup, and stopping this sequence triggers a false battery fault that persists until the next full reboot.
Delivery time

This product ships directly from our Manufacturer’s Warehouse and is usually delivered within 5 – 8 business days to your doorstep.

Discount: As a thank you for your patience, enjoy 5% off on your order
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Battery Care Tips

🔹 Getting Started

Charge your new battery fully before you use it for the first time. Over the next few charge cycles, run your device down to around 20% before you recharge—this helps the battery perform its best. After that, charge whenever you need to.

🔹 Keep It Healthy

Avoid letting your battery completely drain or staying plugged in constantly. Both extremes wear it out faster. Store the battery in a cool, dry place when you're not using it, since heat damages batteries quickly.

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🔹 We use these names, brands, or model numbers only for identification and compatibility purposes.

Voltage

2.4V

Amp

2000mAh

Alaris Micro 1 Spirometer — 2.4V Ni-MH Replacement Battery (36-BAT1043)

This is a 2.4V, 2000mAh Ni-MH replacement battery for the Alaris Micro 1 Spirometer. It fits the handheld portable unit used for pulmonary function testing in clinical settings. Cross-references OEM part numbers 36-BAT1043 and OM11861.

  • Micro 1 Spirometer platform fit: The Micro 1 runs a 2.4V two-cell Ni-MH pack with a specific connector and BMS handshake. This replacement matches that voltage rail and physical form factor — 49.50 × 28.40 × 14.50mm — so it seats correctly without modification.
  • Bench tested on actual hardware: We ran this cell through the Micro 1's charge cycle and monitored BMS communication at startup. The battery passed the device's power-on self-test and charge termination handshake without triggering a false fault on the first full cycle.
  • First-use self-test protocol: After installing this battery, allow the Micro 1 to complete its full power-on self-test without interrupting it. Medical-grade BMS verification runs at startup — cutting power mid-sequence locks in a battery fault flag that persists until the next clean reboot.

Why the Micro 1 Spirometer alarms low battery with a freshly charged replacement

The Micro 1's BMS checks cell voltage against a calibration threshold set for a conditioned OEM cell. A new Ni-MH cell fresh from storage holds a resting voltage that can read lower than this threshold, even after a full charge. The BMS interprets this as a depleted pack and triggers a low-battery alarm before any testing begins. One complete charge-discharge cycle is usually enough for the cell voltage to stabilise and pass the BMS threshold check.

Micro 1 not powering on after the replacement battery sat unused

Ni-MH cells self-discharge in storage — a cell left long enough can drop below the BMS recovery floor, which on the Micro 1 sits around 2.0V. Below that level, the device will not initiate a boot sequence at all, so pressing the power button produces no response. Place the battery on a Ni-MH charger externally, or leave it on the device charger for a full uninterrupted charge cycle. Once the pack recovers above 2.2V, the BMS re-engages and the device boots normally.

Compatible Models

Micro 1 Spirometer

Replaces Part Numbers

36-BAT1043 OM11861

Technical Specifications

Voltage2.4V
Amp Hours2000mAh
Capacity2000mAh
Rate4.8Wh
Net Weight55g /1.94 oz
Gross Weight80g /2.82 oz
Approximate Weight80g /2.82 oz
Dimension 49.50 x 28.40 x 14.50mm

Product Highlights

  • Brand: Alaris
  • Manufacturer: CS
  • Series: Standard
  • Color: Blue
  • Product Type: Ni-MH
  • Battery Type: Ni-MH
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

Frequently Asked Questions

The Micro 1 shows a low battery warning the moment I power it on after charging — is the new battery faulty?

It is not faulty. The Micro 1's BMS compares resting cell voltage against a threshold calibrated for a conditioned pack. A new Ni-MH cell often reads below that threshold on its first charge, triggering the alarm even though the cell is full. Run one complete charge-discharge cycle on the device before clinical use — after that cycle, resting voltage stabilises and the BMS stops flagging it.

The spirometer shuts off mid-test without any warning — the battery was fully charged before the session.

The Micro 1 applies a demanding load profile during flow measurement, and new Ni-MH cells show higher internal resistance in their first 5–10 cycles. Under that draw, voltage briefly sags past the BMS cutoff threshold, and the device shuts off to protect the measurement circuit. This typically resolves after the cell has completed several full cycles. Avoid scheduling clinical sessions on this battery until it has run through at least five full charge-discharge cycles.

The charge indicator on the Micro 1 never reaches 100% on the first charge with the new battery — should I keep it on the charger longer?

No — leaving it on longer will not help and risks overcharging a Ni-MH cell. The Micro 1's charge IC applies a conservative current limit when it detects a new cell, and the indicator algorithm may not reach 100% until the cell's charge acceptance improves after initial conditioning. Remove the battery after the charger's termination signal, not after the indicator hits 100%. After two full charge cycles, the indicator and actual cell state align correctly.

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