---
title: "21700 Battery — £26K/yr Amazon UK Niche (2026) - Flapen"
canonical_url: "https://flapen.com/research/uk/electronics-photo/21700-battery"
last_updated: "2026-07-31T08:42:04.141Z"
locale: en
meta:
description: "Niche score 40/100 · £26K/yr market · 65K searches/yr · £14.80 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:description": "Niche score 40/100 · £26K/yr market · 65K searches/yr · £14.80 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:title": "21700 Battery — £26K/yr Amazon UK Niche (2026) - Flapen"
---
# **21700 battery**
**Skip it**
A small market ($26K/yr) — this niche doesn't clear our bar today.
Market size 7Growth 18Conversion 34Competition 19Returns 95Price range 36Avg price 73Brand share 10Review moat 98Quality gap 96
**Review moat**
**Incredible****41**
avg incumbent reviews — the moat a new listing must climb
**Quality gap**
**Incredible****3.9★**
avg incumbent rating — lower means beatable quality
**Returns**
**Incredible****1.0%**
return rate — above 5% kills the launch gate
**Avg price**
**Good****£14.80**
avg listing price — sweet spot $15–$100
**Price range**
**Okay****£5.23–£20.40**
cheapest to priciest tracked listing — scored on the share inside $15–$100
**Conversion**
**Okay****2.8%**
search→purchase rate — share of searches ending in a sale
**Competition**
**Bad****78%**
top-5 click share — a locked-up shelf
**Growth**
**Bad****-13.9%**
90-day search growth — must beat 0% to launch
**Brand share**
**Bad****96%**
top-5 brand share — brand-locked demand
**Market size**
**Bad****£26K**
£26K/yr · 65K searches
**Signals**[** Low Review Barrier**](https://flapen.com/research/niches?market=uk&signal=low_review_barrier "Top brand's reviews < 500") [** Quality Gap**](https://flapen.com/research/niches?market=uk&signal=quality_gap "Avg rating < 4.0")
According to Flapen's Amazon United Kingdom niche tracking, 21700 battery is a £26K/yr Amazon United Kingdom market (65K searches/yr). The top 5 brands hold 96% of demand. Verdict: Skip it — 40/100.
Data updated Jul 22, 2026 · scored weekly · [~~How we score niches ~~](https://flapen.com/research/methodology)
## **21700 battery market data**
- **Units sold / yr**
- **3K–3K**
- avg 100–250/product
- **Revenue / yr**
- **£37K–£44K**
- units × avg price
- **Conversion rate**
- **2.8%**
- **Avg BSR**
- **#116**
- **Page quality**
- **0%**
- **Prime**
- **100%**
- **Sponsored**
- **27%**
- **Out of stock**
- **10.8%**
- **Avg brand age**
- **27 months**
- **Avg seller age**
- **295 days**
## **Competition & brand share**
The top 5 products capture 78% of clicks — a locked-up shelf that new listings rarely crack.
**Brands**
**7 **▼falling
**Sellers**
**11**
**Top-5 brand share**
**96%**
Top 20: 100%
**Top-5 click share**
**78%**
Top 20: 100%
**Open market**
**1%**
- Global Rankings31% - JESSPOW27% - VOOPOO19% - Efest12% - VENNERLI6% - fenix3% - Open — no brand owns it (1 brand, 1%)
## **Demand & seasonality**
Weekly Amazon search volume, last 104 weeks — -13.9% search growth over the last 90 days.
2K1KHoliday '24Spike '25Black Friday '25Spike '26 seasonSepDecMarJunAugNovMarMay
No pronounced peak months · busiest ÷ quietest = 1.4×
[**Open Trend **](https://flapen.com/research/uk/electronics-photo/21700-battery/trend)
## **Top 21700 battery search terms**
- **21700 battery**50K/yr-13.3%3.3% conv. - **21700 vaping battery**6K/yr-6.6%6.3% conv. - **21700**5K/yr-0.4%1.9% conv. - **21700 battery 5000mah**4K/yr-37.9%2.9% conv. [**All search terms **](https://flapen.com/research/uk/electronics-photo/21700-battery/search-terms)
## **Top 21700 battery products on Amazon**
Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.
0%10%£3K20%£5K30%£8K40%£11K1101001K Reviews — right = deep review moatMarket share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)1 product missing review or click data not plotted
All 11 tracked products in this niche — three views at once, no toggling.
### **Top sellers**
by 90-day click share
[1**3.7 Volt Rechargeable Batteries 5000mAh High Capacity Flat Top Battery for Flashlights Headlamps (Pack of 221 X 70mm)**JESSPOW**£15.15**4.1★25 rev](https://www.amazon.co.uk/dp/B0GD6QL6KM) [2**Molicel P42A 4200 mAh 45A Size: 21.7K High Amp Flat Top Battery No Nicotine**VOOPOO**£17.83**4.0★81 rev](https://www.amazon.co.uk/dp/B0CF9F1WPG) [3**P42A 21/700 4000mah Rechargable Compatible With Vapcell Products - For E-Cigarette Ecig Vape Mods/Kits + 10ml Nightmare Juice Nicotine Free (2 Pack)**Global Rankings**£16.46**2.5★5 rev](https://www.amazon.co.uk/dp/B0FBGP7VJT) [4**21/700 6000mAh Highest MAH Red Compatible With Fogstar Energy Works 10A Rechargeable Cell With Sub Ohm Kit No Nicotine + Band (2 PACK)**Global Rankings**£20.40**3.0★2 rev](https://www.amazon.co.uk/dp/B0G1C2PY6B) [5**4000mAh Green 217/00 Compatible With Fogstar Energy Works With Sub Ohm Kit + Band No Nicotine (2 Pack)**Global Rankings**£16.47**4.1★32 rev](https://www.amazon.co.uk/dp/B0F4H1H5TG)
**~~View all top sellers →~~**
### **Newest**
by launch date
[![Voopoo Argus XT Vape Kit [Silver Grey] - Available in 5 colours - 3A Fast Charge 18650/21700 Battery (SOLD SEPARATELY) 100W - Compatible with MAAT Tanks & TPP Coils - No Nicotine](https://m.media-amazon.com/images/I/41Mn0NNDUzL.jpg)**Voopoo Argus XT Vape Kit \[Silver Grey\] - Available in 5 colours - 3A Fast Charge 18650/21700 Battery (SOLD SEPARATELY) 100W - Compatible with MAAT Tanks & TPP Coils - No Nicotine**Survival Boyz**£16.36**55 rev5mo ago](https://www.amazon.co.uk/dp/B0GN2L7JDV) [![EFEST 3000 Rechargeable Battery with Protective Case [Single]](https://m.media-amazon.com/images/I/318Ytssn5RL.jpg)**EFEST 3000 Rechargeable Battery with Protective Case \[Single\]**Efest**£7.86**0 rev6mo ago](https://www.amazon.co.uk/dp/B0GGGQGX5B) [**3.7 Volt Rechargeable Batteries 5000mAh High Capacity Flat Top Battery for Flashlights Headlamps (Pack of 221 X 70mm)**JESSPOW**£15.15**25 rev6mo ago](https://www.amazon.co.uk/dp/B0GD6QL6KM) [**VENNERLI Rechargeable Lithium Batteries with USB-C Cable Fast Charging Battery 3.7V 7400mWh High-Capacity 2000+ Cycles Ultra-Long Lasting Time Durable Cycle Smart Charging LED Indicator (2-Pack Set)**VENNERLI**£13.03**36 rev7mo ago](https://www.amazon.co.uk/dp/B0G4RLWVG1) [**21/700 6000mAh Highest MAH Red Compatible With Fogstar Energy Works 10A Rechargeable Cell With Sub Ohm Kit No Nicotine + Band (2 PACK)**Global Rankings**£20.40**2 rev8mo ago](https://www.amazon.co.uk/dp/B0G1C2PY6B)
**~~View all new products →~~**
### **Trending**
90-day click momentum
[![Voopoo Argus XT Vape Kit [Silver Grey] - Available in 5 colours - 3A Fast Charge 18650/21700 Battery (SOLD SEPARATELY) 100W - Compatible with MAAT Tanks & TPP Coils - No Nicotine](https://m.media-amazon.com/images/I/41Mn0NNDUzL.jpg)**Voopoo Argus XT Vape Kit \[Silver Grey\] - Available in 5 colours - 3A Fast Charge 18650/21700 Battery (SOLD SEPARATELY) 100W - Compatible with MAAT Tanks & TPP Coils - No Nicotine**Survival Boyz**£16.36**3.6★**▲ 163%**](https://www.amazon.co.uk/dp/B0GN2L7JDV) [**3.7 Volt Rechargeable Batteries 5000mAh High Capacity Flat Top Battery for Flashlights Headlamps (Pack of 221 X 70mm)**JESSPOW**£15.15**4.1★**▲ 129%**](https://www.amazon.co.uk/dp/B0GD6QL6KM) [![EFEST 3000 Rechargeable Battery with Protective Case [Single]](https://m.media-amazon.com/images/I/318Ytssn5RL.jpg)**EFEST 3000 Rechargeable Battery with Protective Case \[Single\]**Efest**£7.86**0.0★**▲ 112%**](https://www.amazon.co.uk/dp/B0GGGQGX5B) [![EFEST 3500 Rechargeable Battery 20A with Protective Case [Pack of 2]](https://m.media-amazon.com/images/I/41N7niQgEzL.jpg)**EFEST 3500 Rechargeable Battery 20A with Protective Case \[Pack of 2\]**Efest**£18.68**4.7★**▲ 62%**](https://www.amazon.co.uk/dp/B0FS1MCPRD) [![EFEST 3000 Rechargeable Battery with Protective Case [Pack of 2]](https://m.media-amazon.com/images/I/41z-pwt691L.jpg)**EFEST 3000 Rechargeable Battery with Protective Case \[Pack of 2\]**Efest**£15.31**3.5★**▲ 34%**](https://www.amazon.co.uk/dp/B0DXDQJ4H7)
**~~View all trending →~~**
## **What buyers say about 21700 battery**
What buyers praise and complain about, mined from review topics.
### **What buyers love **
**Battery Life**24%
*“Great batteries”*
**Charging**23%
*“Brilliant Charger”*
**Quality-Overall**12%
*“Good quality”*
**Value For Money**6%
*“great value for money”*
**Durability**5%
*“The brand highlights durability”*
**Ease Of Use**3%
*“Easy to use”*
**Size-Overall**3%
*“they fit perfectly”*
**Advertised Vs Actual Product**3%
*“As Described”*
**Strength**2%
*“they feel sturdy”*
**Storage Capacity**2%
*“Good capacity”*
### **What buyers complain about **
**Charging**14%
*“will not charge”*
**Size-Overall**9%
*“they are an odd size”*
**Battery Life**8%
*“cost a fortune in different batteries”*
**Advertised Vs Actual Product**7%
*“This should really be stated clearly in the listing to avoid confusion”*
**Storage Capacity**4%
*“Not as good in capacity as the normal ones”*
**Measurement/Reading Accuracy**4%
*“Mah not accurate”*
**Value For Money**2%
*“These batteries are a little higher in price than average”*
**Adhesion/Stickiness**2%
*“Not for vape covered with a sticky lable”*
**Functionality-Overall**2%
*“Worked great until the insulation came off the positive end”*
**Touch/Button Controls**2%
*“Not many controls”*
### **Top return reasons **
**Size-Overall**61%
**Charging**11%
**Compatibility-Overall**8%
**Functionality-Overall**7%
**Battery Life**4%
**Advertised Vs Actual Product**3%
**Defective Material/Parts**3%
**Durability**2%
**Thickness**1%
**Adhesion/Stickiness**0%
## **Common questions**
- **Is 21700 battery profitable to sell on Amazon United Kingdom?**
- The niche generates £26K/yr across 11 tracked products. 3 of 6 products launched in the last 360 days are still selling. 90-day search growth is -13.9%. Flapen's verdict: Skip it (40/100).
- **How competitive is the 21700 battery niche?**
- 7 brands and 11 sellers compete. The top 5 products take 78% of clicks and top 5 brands hold 96% of demand.
- **What do buyers complain about in 21700 battery?**
- Top complaints mined from reviews: Charging, Size-Overall, Battery Life. The return rate is 1.0%.
- **When does demand for 21700 battery peak?**
- Demand is steady year-round — the busiest month runs 1.4× the quietest.
- **What does it cost to enter the 21700 battery niche?**
- Listings span £5.23–£20.40; the average listing price is £14.80 (sweet spot $15–$100). The average incumbent carries 41 reviews — the moat a new listing must climb.
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