Welcome to our store. Your trusted source for batteries and power solutions. Learn more

For support or quotes: sales@batteryweb.com
WELCOME5
BatteryWeb

REA CARD Rea T6 Flex Compatible Battery 3.7V 3400mAh

Up to 20% off
New arrival
From $25.99 USD $31.99
Shipping calculated at checkout.
Fits REA CARD Rea T6 Flex payment terminal, replaces OEM battery CS-IML220HL.
3.7V 3400mAh lithium-ion cell powers the entire transaction cycle without mid-sale shutdowns.
Connector seats vertically into the terminal's top battery slot with positive contact facing upward.
We ran load cycles through a live POS environment; BMS accepted handshake on first boot with stable voltage regulation under printer and wireless draw.
After installation, complete one full transaction cycle before deploying in a live environment — the terminal maps battery capacity during normal operation and requires at least one complete power cycle to calibrate the charge indicator correctly.
Visa Mastercard American Express PayPal Apple Pay Google Pay Shop Pay Discover Klarna Afterpay Stripe
✦

Check that your old battery model number and device model to match our description. This makes sure they work together.

✦

We ship your order same day if you buy it before 4 PM EST.

Warranty

Let customers speak for us

from 11 reviews

Product is exactly as described and arrived quickly

Robert Jones
Rocket ES4-12 Compatible Replacement Battery

It took a bit longer than expected, likely due to the holiday season, but that was understandable. So far, the battery seems to be working well!

Linda M.
MGE UPS Systems Pulsar EX 1500RT Compatible Replacement Battery By Bright Way

Excellent substitute for the original, appearing to be the perfect replacement.

Alberto J.
APC SMART-UPS RT SURTA3000RMXL3U UPS High Performance Replacement Battery Set

It was what i was looking for. Support is fast

Jaswal
WAHEGURUG - RADHASWAMI

Fast service

Mark Casias
BatteryWeb

Perfect fit

Mark Casias
STX20L-BS Battery for Harley Softail FLS FLST 1991-2017 High Performance

Works Perfectly!!

Ben Benson
Invacare 220 Scooter High Performance Medical Replacement Battery Set

Send Your Battery Photo

Expert Technician Help

Snap a photo or video of your battery and send it to us. We'll identify the exact replacement—fast and hassle-free. Our team has helped thousands of customers find the right battery quickly and easily.

POST YOUR BATTERY IMAGE
Product & Solutions Expert

Product & Solutions Expert

✉ sales@batteryweb.com

🔹 10+ Years Battery Experience 🔹 Fast & Accurate Identification

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.

Delivery and Shipping

🔹 Most orders ship the next day, and we use FedEx, UPS, Purolator and other carriers to get them to you. Lithium batteries have to ship by ground only, not air or USPS. Make sure your address is right before you order, because if we have to send it back, you pay for shipping again.

Disclaimer

⚠️ Disclaimer: All product names, trademarks, and registered trademarks belong to their respective owners.

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

Voltage

3.7V

Amp

3400mAh

REA CARD Rea T6 Flex — 3.7V Li-ion Replacement Battery

This 3.7V 3400mAh Li-ion battery replaces the original cell in the REA CARD Rea T6 Flex payment terminal. It fits the Rea T6 Flex portable card reader used at point-of-sale locations. Voltage and capacity match the original spec exactly — 3.7V, 3400mAh (12.58Wh).

  • Rea T6 Flex fit: The T6 Flex uses a single-cell Li-ion pack at 3.7V nominal. The terminal's charge IC and BMS handshake are matched to this cell voltage and capacity class. Swapping to an incorrect voltage will prevent the PCI boot sequence from completing.
  • Bench tested on actual hardware: We cycled this battery through charge and discharge on a cell analyser and monitored BMS cutoff thresholds. The protection circuit tripped correctly at both ends — no undervoltage or overvoltage events during testing.
  • First deployment tip: After installation, complete one full transaction cycle before putting the terminal into live service. The Rea T6 Flex maps battery capacity during normal operation and needs at least one complete power cycle to calibrate the charge indicator correctly.

Terminal not completing PCI boot sequence after battery swap

The Rea T6 Flex runs a PCI security boot check on every power-on. If the battery voltage sits below roughly 3.5V when the terminal first starts, the boot sequence can stall or loop before reaching the home screen. A new cell shipped at storage charge — typically 3.6–3.7V — can sit right at that threshold. Plug the terminal into its charger for 15–20 minutes before the first boot, then power on. That brings the cell above the minimum voltage the PCI firmware expects to see.

Terminal reboots mid-transaction during receipt printing

The receipt printer motor draws a short current spike — often 0.8–1.2A — on top of the display and wireless radio load already running. If the battery cell is degraded or the BMS overcurrent threshold is set conservatively, that combined spike can trip a protective cutoff and reboot the terminal. On a fresh replacement battery, this usually points to a loose battery connector rather than a cell fault — reseat the connector and confirm contact pressure. If the reboot persists, check that the terminal firmware has completed its first full charge-discharge calibration cycle, as an uncalibrated state can cause the BMS to misread current draw.

Compatible Models

Rea T6 Flex

Technical Specifications

Voltage3.7V
Amp Hours3400mAh
Capacity3400mAh
Rate12.58Wh
Net Weight53g /1.87 oz
Gross Weight78g /2.75 oz
Approximate Weight78g /2.75 oz
Dimension 66.00 x 21.80 x 18.50mm

Product Highlights

  • Brand: REA CARD
  • Manufacturer: CS
  • Series: Standard
  • Color: Blue
  • Product Type: Li-ion
  • Battery Type: Li-ion
  • Warranty: 12 Months
  • Bulk Orders: sales@batteryweb.com

Frequently Asked Questions

My Rea T6 Flex won't turn on at all after sitting in a drawer for a few months — is the new battery dead too?

A terminal left unused will self-discharge the original cell below the BMS recovery threshold — sometimes as low as 2.5V — and the protection circuit locks out to prevent damage. A brand-new replacement battery won't have that problem, but if the terminal itself isn't responding, connect it to the charger for at least 20 minutes before attempting to power on. The charge IC needs time to trickle-charge the cell back above the 3.0V recovery threshold before the BMS will allow a normal boot. If the terminal still won't respond after 20 minutes on charge, confirm the charger port and cable are seating correctly.

The battery indicator is stuck at 99% and won't move — did I get a faulty battery?

This is normal on a new cell. The Rea T6 Flex charge IC enters a top-off mode when it detects a high state-of-charge, which holds the display reading at 99% while it trickles in the final fraction of capacity. It is not a fault. Run the terminal through one complete transaction session until the battery drops to around 80%, then charge it back to full — after that cycle, the charge indicator will track normally.

The terminal gets noticeably warm during a busy period and the battery drains faster than expected — what's causing that?

During heavy use, the Rea T6 Flex is simultaneously driving the touchscreen backlight, the NFC or card reader module, the wireless radio, and the receipt printer — combined draw adds up quickly and generates heat as a byproduct. That is normal operating load for a portable POS terminal, not a battery fault. What accelerates drain is keeping screen brightness at maximum or leaving Bluetooth and Wi-Fi active when not needed. Reduce screen brightness and disable unused radios to bring the thermal load down and extend the charge between transactions.

Payment & Security

Payment methods

  • American Express
  • Apple Pay
  • Diners Club
  • Discover
  • Google Pay
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.

Related Products

Ingenico Iwe280 Replacement Battery, 3.7V, 3400mAh, Li-ion 1

Engineered for Performance. Built to Last.

Check out our top-rated selection of reliable products built to last. We offer high-quality options that deliver consistent performance for all your needs.

Our Collections