The B-S2 battery model name, also searched as BS2 or b s2, is the 5000 mAh pack that replacement listings match to the vivo Y33s with model number V2109. The listings agree with each other, and the capacity matches what vivo advertises for the phone.
The neighbouring code B-S1 causes most mistakes, because it also turns up in Y33s searches. B-S1 is a 4900 mAh pack linked to other model numbers, so the V-number of your phone settles which one you need.
Quick facts
The phone that uses the B-S2 battery model name
Seller after seller lists B-S2 for the vivo Y33s, V2109. We found no second phone named consistently, so the fit list stays short. If you own another Y-series phone, do not assume B-S2 fits; look up its own code on the vivo battery model list.
Our vivo Y33s battery page covers the phone side of the same question.
B-S2 or B-S1: settle it with the V-number
| Code | Linked model numbers | Listed capacity |
|---|---|---|
| B-S2 | V2109 (Y33s) | 5000 mAh |
| B-S1 | V2135, V2110 and others | 4900 mAh |
Find the V-number under Settings, then About phone. If it reads V2109, B-S2 is the code to ask for.
Ordering a genuine B-S2 pack
vivo service centres fit original packs and keep the old one for safe disposal. If you buy from a shop, ask for the cell to be weighed against your old pack and check that the label shows B-S2, 5000 mAh and a batch line. A label with only "for vivo" and no code is a generic copy.
A Y33s that has been dropped and now runs warm with the screen off may have a damaged B-S2 cell. Do not charge it overnight; get it inspected first.
Typical and rated capacity
vivo advertises 5000 mAh, and that is the figure on most listings. The minimum figure on the cell sticker may read slightly below 5000. If the B-S2 runs near 3.87 V, as most vivo Y cells do, it stores about 19 to 19.5 Wh. Read more on our battery capacity page.
When to replace the Y33s battery
Three signs mean the B-S2 is done: a Y33s that cannot reach the evening even after a restart and a clean full charge, sudden shutdowns at 20 or 30 percent, and any gap opening between the frame and the back. Many owners find a fresh B-S2 makes an older Y33s feel new again, which is cheaper than buying a new phone.
Getting the most from a Y33s battery
The Y33s charges at 18 W, so it is slower than newer vivo phones and gentler on the cell. Most wear comes from heat: gaming while plugged in, a Y33s left in a parked car in summer, or a charge under a quilt. Keep it cool and the B-S2 will age slowly.
vivo's software has a power saving mode and lets you see which apps use the most charge. Both sit in the battery part of Settings; typing "battery" into the Settings search field jumps straight there. Turning down screen brightness and closing location for apps that do not need it often adds an hour or more to the day.
B-S2 battery model name: what to say at the counter
Ask for "a B-S2 battery for vivo Y33s, model V2109" in one sentence, so the shop cannot swap in a B-S1 by mistake. If they only have a pack with a blank label, wait for a proper one. A day or two without the phone is better than a pack that swells within a few months.
Frequently asked questions
Which phone has the vivo B-S2 battery?
The vivo Y33s with model number V2109, according to consistent replacement listings.
What is the mAh of B-S2?
5000 mAh, the same capacity vivo advertises for the Y33s.
Are B-S2 and B-S1 the same?
No. B-S1 is a 4900 mAh pack linked to other V-numbers. Check your model number before buying.
Is BS2 the same code as B-S2?
Yes. People often leave out the hyphen when searching.
How much does a B-S2 weigh compared with a copy?
We do not have an official weight, but a genuine 5000 mAh cell feels noticeably heavier than a cheap copy. Compare the new pack with your old one in the hand.