Metz 9637 Flash Replacement Battery 6V 4200mAh Ni-MH
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.
Metz 9637 Flash Replacement Battery 6V 4200mAh Ni-MH - is backordered and will ship as soon as it is back in stock.
Let customers speak for us
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
✉ sales@batteryweb.com
Battery Care Tips
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
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
⚠️ 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.
Metz 9637 Flash Replacement Battery 6V 4200mAh Ni-MH - is backordered and will ship as soon as it is back in stock.
Voltage
6V
Amp
4200mAh
Metz 9637 / 9702 / 9704 / 9705 Series — 6V Ni-MH Replacement Battery
This is a 6V 4200mAh Ni-MH replacement battery for Metz professional flash units, including the 9637, 9702, 9704, and 9705 models. It slots into the battery compartment where the original Metz cell sits and restores flash operation without modification. Dimensions are 88.95 x 47.55 x 36.50mm — confirm against your existing pack before ordering.
- Multi-model flash platform fit: The 9637, 9702, 9704, and 9705 share the same battery bay dimensions and 6V supply rail. The flash capacitor charging circuit draws from this voltage directly, so a correctly rated replacement restores full guide number output without retuning the unit.
- Bench tested on actual hardware: We cycled this cell through repeated capacitor charge-drain sequences on a Metz flash chassis. The cell held voltage through multiple consecutive full-power pops without triggering a low-voltage cutoff.
- First-cycle charging on Metz flash units: Ni-MH cells shipped in storage state may read as flat on the flash's charge indicator. Run one full charge in the Metz charger before shooting — the indicator circuit calibrates against a charge curve, not resting voltage, and will read inaccurately until that first full cycle completes.
Flash output dropping mid-shoot on a fresh Ni-MH cell
Ni-MH cells deliver voltage that sags under the high instantaneous current the capacitor pulls during recharge. At full guide number, a 9637 flash draws a significant surge from the cell each time the capacitor tops up. If the cell has not been properly conditioned, internal resistance is higher than rated, which amplifies this sag. Run two to three full charge-discharge cycles through the Metz charger and the sag narrows as the cell reaches rated internal resistance.
Flash recycling time getting longer as the shoot progresses
Recycling time is directly tied to how fast the cell can push current into the capacitor circuit. As cell voltage drops through the discharge curve, recharge current to the capacitor decreases and recycle time stretches. This is normal Ni-MH behaviour, not a faulty cell — it happens near the end of a charge cycle when cell voltage falls below roughly 5.4V. Stop shooting, recharge fully, and recycle time returns to the fast end of the spec range.
Compatible Models
Technical Specifications
Product Highlights
- Brand: Metz
- Manufacturer: CS
- Series: Standard
- Color: Black
- Product Type: Ni-MH
- Battery Type: Ni-MH
- Warranty: 12 Months
- Bulk Orders: sales@batteryweb.com
Frequently Asked Questions
My Metz flash is showing a full charge indicator but fires weakly and won't recycle — is the new battery the problem?
Weak output with a full indicator is almost always high internal resistance in an unconditioned Ni-MH cell, not a defective unit. The flash indicator reads resting voltage, which looks healthy, but the cell can't sustain the current surge the capacitor needs at full power. Run three full charge-discharge cycles through the Metz charger before judging output. After conditioning, internal resistance drops and the capacitor charges at the rate the unit was built around.
The battery percentage on my flash is jumping around — it shows half charge, then nearly empty, then climbs back up mid-shoot.
Ni-MH cells have a flat discharge curve through most of their range, then voltage drops sharply near the end. The Metz indicator is mapping voltage readings to percentage, and a new cell's discharge curve may not align perfectly with the original calibration. The jumps are most pronounced in the lower third of charge. Keep the cell topped up and the indicator stabilises — erratic readings in the top half of the charge range usually settle after the cell has been through a few full cycles.
I shot in cold conditions and the cell went flat far faster than at room temperature — is this a fault?
Ni-MH chemistry loses usable capacity as temperature drops — internal resistance rises and the voltage sag under capacitor recharge current cuts the cycle short before the cell is actually empty. This is a chemistry limitation, not a defective cell. At temperatures below around 10°C, expect noticeably fewer full-power pops per charge. Keep a spare cell in an inside jacket pocket to stay warm and swap mid-shoot if recycle times start stretching.
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
Related Products
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.






